Understand Your All-Wheel-Drive System | Know it All with Jason Cammisa | Ep. 04

[@SuperGoooooooof]

I joined this channel just for Jason

[@TechnoLawyer]

Same.

[@kjyu]

Same

[@pbjracing14yearsago49]

Same

[@TheJamrockJay]

Same

[@jasondk5127]

Yes me too that's my name too😝

[@TML34]

Jason, you need a part 2. There’s so many other variants of AWD systems that I’d like you to complain about. 😀

[@four4our4our46]

^this

[@robertelmo7736]

Can you also talk about putting a slightly larger tire on a regular AWD car to get the 1.05 turns in the rear? LOL Killer video...but we need the difference between 4WD and AWD explained as well. Thumbs up...

[@adnanjusic4890]

YEAH.. WHAT ABOUT 4MATIC ?

[@HimTortons]

@@adnanjusic4890 I'd think that 4MATIC is pretty the same principle as BMW's xDrive, or is it not?

[@adnanjusic4890]

@@HimTortons Dont know, maybe. Why Jason did'nt mention it..

[@jasonchatham4170]

This channel better keep Cammisa or we will all just drift over onto whatever channel will pay him enough to stay. One of the best car guys on YT and other channels have messed up not keeping him.

[@fernandopagnotta58]

is he still?

[@dobrivojemutavdzic6705]

This guy is, arguably, the best automotive journalist I have seen in a very long time! Bravo Jason

[@James_cowley]

So where does the Subaru system fall? Asking for all the Subaru vapey bois. Thanks

[@JesterialInsanity]

I like how there’s an entire video on AWD Systems, and they don’t mention Subaru even once.

[@kw2519]

Subaru doesn’t exist in Jason’s world. Subawho?

[@TML34]

The head gaskets fail so often you forget about the awd nonsense. Zing!

[@benjaminstuart8626]

I agree, I wanted an explanation for my STI

[@rickharper1497]

Subaru vehicles equipped with manual transmissions use a viscous limited slip center differential (VCD) AWD system

[@jasonbeallie5535]

As an owner of a 2018 Subaru Forester XT I'm surprised to see that you didn't mention Subaru's symmetrical AWD.

[@S50Sinner]

He did mention Audi's system, which is basically identical (they're both Torsen systems). I say this as someone who went from a WRX to an A4, aside from the A4 having an open rear diff vs the WRX's LSD, both behaved mearly identical.

[@jbrovage]

@@S50Sinner my understanding was that the TORSEN Audi's of the 80's are all but gone now, replaced by versions more like the Haldex system. "Quattro" used to mean "symmetrical AWD", but no longer.

[@S50Sinner]

@@jbrovage Torsen is still present on all S ans RS models (excluding the TT and type 3) and was on the base models as well until 2015 when a Haldex-like system was introduced for certain A models. Needless to say, the A3 and TT have been Haldex all along.

[@buskE46]

@@jbrovage I have a rare AWD system in my rig and would like to have Jason give it the rundown. Apparently in 1999 Chevy had some sort of agreement with Subaru... LSS - My 1999 Suburban has 3 modes for the drivetrain - "2WD" (Rear only), "Auto 4WD" (employs some Subaru derivative for when wheel spin in detected, it will engage the front) and then "4WD" where it locks it all in, lets me drive in 3ft of snow but only in a straight line.

[@victorteran9766]

I am also intrigued, seems Subaru has like 4 different AWD systems right now, based on clutch packs and viscous diffs, wonder if that makes a difference in handling. For example I own a 6MT Crosstrek, dont know if it is Torsen or what kind, but it works amazing on dry surfaces but doesnt give me optimal traction on wet, slippery ones when I try to drive fast.

[@girtsberzins2970]

too short, need more Cammisa this week...

[@renansilveira2013]

Search "Camisa" in Portuguese and I hope you'll find your sentence funny like I found

[@jason86768]

Love that 78/79 ford at the beginning!

[@evanswift5020]

I got murdered on the golf R subreddit a few weeks ago for dropping this knowledge. lmao

[@tanktheram]

As I was about to comment... my MK7.5 R (2019) would rotate under power in snow forsure, wet most of the time, and dry sometimes. It had to do with tire choice and setting in the computer. On snow tires, it would rotate easily in snow by stabbing the gas, flicking in, letting off and stabbing again to hold the drift. Wet wasn't too hard and It took more work but also would in dry. On summer tires it understeered heavily following this practice, likely because the rear didn't have enough power to overcome the traction in the front. Oddly enough, it would only power on drift in Normal drivetrain and Suspension mode in the dash. Race mode again made it understeer, sometimes even in snow.... and I think this is because the car was then programmed in Race mode for throttle lift oversteer like a FWD car. Likewise, my quickest times 1/4 & 0-60 were in Custom mode. Suspension hard for less weight transfer, drivetrain in Normal, Steering in comfort. In Race mode setting it would smoke the front tires until the rear diff kicked in and it was abrupt making a whirr as it did it. In Normal it would squat and rocket like you'd expect. Possibly because Normal is locking the coupler sooner, expecting snow? That was my thought. It also wasn't stock power with the 7speed DSG. If you're not familiar these settings I talk of, they are pre programmed and selectable. Comfort, Normal, Race and Custom. I liked the car, just had to know how to modify the Suspension and Drivetrain settings for your driving.

[@pandapv]

@@tanktheram You're describing the Scandinavian flick (basically what was being described in the audi section), which is by definition not rotation under power. You are using the change in weight distribution in the car caused by letting off the gas to rotate the car, but that's not rotation under power. That's what you have to do to get a golf to rotate. There's nothing wrong with that, it just has different handling characteristics (which IMO are much safer for most kinds of street driving), but it does not rotate under power.

[@tanktheram]

@@pandapv while I completely understand that, having been taught and raced under SCCA sanctioning.... plus the memes on the net alone could have taught me that 5 years ago. However once into the slide, the car allowed me to continue the slide with heavy throttle application... meaning he wasn't 100% right. The Golf R would "power on drift" sometimes even without the flick but took LOTS of prodding. What you missed in my extended comment was the fact that depending on drivetrain mode - it would lock the rear sooner or more aggressively for longer.

[@deviouslaw]

@@tanktheramAs Jason said, just own it

[@DanielBellezza89]

depends, I've seen golf R's with programmed Haldex and they do AWD all the time, it can be done safely too, know a guy in town that had a 800hp Golf R with an 07k and had no issues for over 60k miles. That thing wasn't just a straight line monster. It genuinely whooped on track, it turned fast and kept up with a Lamborghini Huracán Performante like it was a video game, I'm not even a good driver and I was able to keep up in the turns and the straight. Full interior no weight reduction.

[@nadersoli815]

I just wanted to say I love you, Jason. There's just no two like you. Period.

[@BryanW916]

The SH-AWD in my Acura TL is surprisingly good. Flooring it around a corner is a blast, it sends power to the outside rear wheel making the car rotate better.

[@drooskeedoo3388]

Not only that it can overrotated the outside wheel. Spinning it faster than it would normally. I have it on my 11’ RDX and it's a blast in the canyons.

[@teedot1186]

Yea. I'm a Audi Quattro guy but that TL is one Asian car I'd own. Nice car.

[@BryanW916]

@@teedot1186 Same! That's why i picked it. It's been a blast to drive. ESP around San Francisco lol

[@MrCalverino]

I love those!!!

[@johnmadsen37]

That’s torque vectoring- very nice. My highlander does that too.

[@palco22]

I've owned several AWD. All power to the front and AWD when required (No driver input) Great system but knowing it's limit is the key. I also owned 4WD (Standard and automatics - locking front hubs and full time hubs) Again, great results but knowing their limits is the key ! The different types of transfer cases is another key point (chain vs geared etc. etc. etc.) The combinations are endless. Over the years I've found that Jeep has one of the better systems (with locking differentials) BUT, knowing it's limits is always the key. Great video !

[@Bmwguy2011]

Outstanding! In 25 years of being a car enthusiast, a past owner of a golf r, Audi quattros, and now Bmw 3 / m3’s, this explains so much. The golf r was brilliant but I hated how hard it was to engage the rear wheels. Another brilliant discussion by Jason!

[@khvidtube1617]

I solved the same problem with my RS3. Get a Haldex controller (you can set 50:50) and have a 2.5 d negative camber for the front wheels.

[@FalkJ]

Good video, so many people that don't understand the difference! One thing though, the SQ5 still has a torsen differential with permanent 4WD and a base 40/60 split, not FWD as stated. The regular Q5 though, and most other quattro models, are unfortunately stuck with the lame FWD so called "quattro ultra" nowadays.

[@MrLukerolla]

Also the 3.0 TDI has torsen in the Q5 the quattro ultra has 500 nm of torque limit

[@jonathanpeterson1]

Generally speaking for Audi: Transverse=Haldex, Longitudinal=Torsen.

[@bennimag2]

@@jonathanpeterson1 true ! So as long as you're dealing with a "big engine" Audi you're not doing so bad ! ;-)

[@cadmando18]

I was going to say this as I own an SQ5, but you said it well and politely. And I will tell anyone who will read it, this SQ5 is so amazing in bad weather, I have never driven anything as good in ice, snow, rain, mud, up hills, down hills... it's good.

[@ALEX20hoc]

@@jonathanpeterson1 no, Quattro Ultra is longitudinal setup with permanent fwd and rear wheels controlled via 2 clutch packs (not Haldex)

[@JayCowan-y3j]

Great video; I learned a lot. Thank you. I love all wheel drive high performance cars. I once had an accident in Austria in my 1997 German-spec BMW 325 ix that ripped off both rear wheels and sent me down an adjacent ski slope. After calling a tow truck that could not get onto the ski slope, I literally drove the BMW down the hill with ONLY the front wheels pulling. So in this case, there was NO power going to the rear wheels because they were literally gone. Yeah, what was left of the rear axles was spinning a bit. But it worked, and drew quite a crowd of skiers who had never seen an all-wheel drive BMW and were stunned to see the front wheels spinning in the snow. One note about clutch packs: Now I drive a BMW X3M Competition and while I love the AWD, I do notice that at crawling speed up a super-steep hill while turning sharply on pavement, there is a bit of "binding" between the front and rear wheels. The computer is probably going crazy trying to manage the clutch packs.

[@BrokeWrench]

That is typically what happens when the wheels are locked together too tightly for the turn. I would assume it is made like that for low speed crawling for maximum traction. I'm actually impressed it does that

[@ZakTheRipper18]

@@BrokeWrench When the steering wheel is at full lock, my STi has that same slight clunk sound and binding. The manual states this is normal.

[@ridgewoodgardens6253]

No one does auto journalism like Jason - GOAT

[@spanky762]

Your videos are like main-lining an automotive engineering degree. Thank you for them, I am learning so much!

[@tkania8888]

Jason for the win. When he left that unmentioned magazine he worked for, I stopped reading it shortly afterwards. Wonderful to see him in front of a camera again. A true car guy.

[@SebastianXe90]

OMG I’ve been waiting years for someone, anyone in the car media industry to rant about fake-ass AWDs (Yes I’m talking about you HALDEX) properly. You are the Best Jason!

[@sage11x]

There’s nothing “fake” about a haldex AWD system. It’s still AWD it’s just that adding a PTU to a front drive car does not suddenly make it handle like a rear wheel drive car. And that’s OK. I have a RWD car for giggles. I have an AWD car to commute in. I don’t care about at the limit handling on my commuter because that’s not what it’s for- it’s for getting my ass to work no matter what BS is happening outside.

[@yosefm170]

Fake? I drive Passat B8 4motion, and on the winter it's very competent. Jason is talking about when you push the car to the limit, but on every day basis it's no different. I also had a Audi Q7, and I didn't really feel that big of a difference on my commute. Btw, I live in Sweden

[@SebastianXe90]

@@yosefm170 Ughh… I don’t think you get what I’m talking about… haldex itself is a genuine awd system and I admit that. If a fwd-based system can send any power to the rear, it is in fact awd. But the fake part is in its marketing approach. All the haldex-using car companies boasts its ability to send 100% of the power to the rear and yet it never can (under normal driving circumstances ofc). This is now misleading consumers and That’s what’s fake about it.

[@yosefm170]

@@SebastianXe90 now I understand what you ment :)

[@JohnDoe-qb6yh]

@@SebastianXe90 is a torsen type amy different?

[@Driftuner]

Oh man, this topic deserves more episodes. When you start throwing your attesas and symetricals into the equasion things get really interesting

[@luismartepr]

I have become addicted to Hagerty and Jason! I wish I had close friends like this with so much knowledge and passion to cars.

[@abishek4300]

And this is why i fell in love with the E63s when it came out with its AWD system... You activate drift mode and you get all those 750Nm going only to the rear wheels... You can turn it off, it's a rear wheel drive based AWD system.... Glad the M5 came with it too afterwards! Such an amazing car the E63s is....!

[@Chris.Davies]

At age 16, I once neglected to take Dad's old 1974 Toyota Landcruiser out of 4WD (H4, not L4) when I got to the bottom of the ski hill. I was a relatively new driver back then. The drive back home was on almost straight roads, but by the time I got home through the city I had almost shredded out a new set of very expensive Firestone Town & Country tyres. My father was not impressed, but he still managed a laugh, and I learned a valuable lesson.

[@tractioncontroldelete]

Pastor Jason preaching the truth!! 🤟

[@aluminumfalcon552]

A mk 8 golf R can send 100% of its REAR axle torque to either side which equates to up to a maximum of 50% of its total torque. This is because it has a clutch pack for each side and can fully engage one side only if needed. Edit: it also does not have a rear differential, only a ring and pinion between the two clutch packs. Very cool design when you look at it.

[@BigUriel]

It's an electronic clutch pack differential like the ones Ferrari has been using for 20 years

[@MistaBrown420]

@@BigUriel except electronics have improved how much ?

[@racerx8410712]

I've lived in MN my entire life and this is about my thirtieth winter season as a driver. I live in a pretty decent sized city (100k) and while I've had AWD vehicles at different times in my life I've kept my wife and I in AWD for the last 5-6 years. We had two wagons: an 06 Audi A6 and 05 Subaru Outback XT, 10 Mitsubishi Endeavor and now 99 CRV and 19 Highlander. The main thing is simply getting around and most any AWD will accomplish this but there is a fun quotient as well and while the wagons did understeer you could get them to rotate. You just have to stay committed (especially in the Audi) or your going to slam a curb. Both were predictable as well and you could drift them back and forth as much as you like correcting them easily with a quick counter on the wheel. I didn't spend much time in the Endeavor but the CRV is very neutral as is the Highlander which is not as much fun but more confidence inspiring. I drive the CRV and love it! I miss the Audi and to some degree the Subaru but they had limited space and required high octane (among other special fluids).

[@GaZaY0UTHchris]

*breathes heavily in subaru*

[@donniebaynard8430]

Dude, Jason may be the smartest person ever!

[@mugmushrooms9845]

Talks about AWD, leaves out Subaru 🤣

[@BashirB]

yeah , i wanted to hear that too . @JasonCammisa

[@saifel-eslamal-labban2163]

He isn't gonna talk about them because subaru has a lot of forms Also he isn't talking about every car manufacturer

[@mmiller1188]

This video was (rightfully) complaining about the Haldex type AWD systems which are found in cars with sideways engines. They really are a bandaid afterthought to a vehicle with a transverse engine and transaxle. Subaru's AWD setups are all very similar to the original Quattro in how they are laid out. - Both are Symmetrical - Both are longitudinal - The front differential is in the lower front part of the transmission, right behind the bellhousing - The engine resides entirely infront of the front axle center. There are differences with the center differential. The basic manual transmissions have a set of spiders gears with a viscous coupler to divide power and are 50/50. Some of the STi can change how the coupler works to set the power distribution. Automatics use a different coupler system without spider gears - CVT ,4EAT and they are front biased but are ALWAYS powering both front and rear at different levels. The old old Subarus just have a lock to lock the center differential; there either 4x4 or front wheel drive. Very similar to the early Audi quattros as well. They were both a longitudinal front wheel drive (ever notice how far back the axle was on the older Audis with longitudinal engines?) with the transaxle / transdiff /whatever looking nearly identical. Then, at some point, the ability to power the rear was added. The true quattros are still just like a Subaru. Whereas the stuff in the Golf and smaller ones are Haldex. Compare items on ebay - 284203799448 is a Subaru 4-EAT transaxle and item 153581209924 is a similar vintage Audi quattro transaxle.

[@kcfreeman3021]

Yeah, subaru is the best.

[@jamesgeorge4874]

@@kcfreeman3021 just save up for regularly scheduled headgasket failure, lol.

[@S50Sinner]

This video just became my anthem, this topic has been my personal crusade for years.

[@Iowa599]

Honda's SH-AWD system is amazingly simple. I'm surprised it wasn't invented decades before, since it was a completely mechanical system when Honda first introduced it in the 1986 Civic Wagovan. (basically it is a 4wd system with a torque converter added in the rear driveshaft to allow f:r axle speed differences)

[@scordatura9259]

They should use it more imo for their performance cars. Fwd civics are good and all but AWD ones will be rad

[@2Meals]

Jason is the reason why I am here!

[@driver_18]

I love these kinds of videos! Now lets hear about Jason’s advice on dodging salesman tricks in charging extra when buying a car

[@1600dennis1]

My 2002 Volvo V70 xc Cross Country is Front Wheel Drive-All Wheel Drive (Haldex). Its wonderful in straight ahead driving, a formidable drag racer on snow & ice-covered roads running studded winter tyres & ok in corners as long as I am careful with the throttle. Take the bend slow & easy & once you get straightened out, hit the throttle. On a snow-covered bend, I gave it too much throttle & it tried seriously to drive off the road. And, once you over-throttle it, nothing gets better, more throttle & your trip to the ditch comes faster. Letting off the throttle & it slowly loses speed, on the wrong side of the road.

[@GregRampersad]

This was one of the best, concise explanations I've seen so far! Kudos!

[@jimmybowtie]

I want to note the BMW Style 5 just in screen and slightly blurred is a work of art.

[@matmoome]

Hagerty keeps forgetting to add their videos to playlists. The Know It All Playlist only has the first 2 episodes in it.

[@ironreed2654]

Yeah, I think he'd still rather be primarily writing for a magazine then KZbin.

[@lesflynn4455]

Somebody please give Jason Cammissa a platform in which to spread his knowledge, wisdom and gripes.

[@mry82]

The video clips for this were awesome, as is Jason. I really like the simplicity and feel of the AWD 62R/38F split in my 01 325xi (originally bought for my wife's snowy commutes, but now my modified toy... it performed well in a moderate amount of snow, even on all seasons, but as a daily it's still fun).

[@JoiceVaderd]

I had an 01 330i. Just rear wheel. With snow tires, it was just fine. RWD works well in the snow. Then I had the opportunity to have a 2010 328i XDrive... All season tires made driving in the snow a piece of cake. The same exact day, it took me half an hour to back into my driveway from the side of the road in my FWD Malibu. Definitely showed me the difference between an AWD system and a 2WD system. Snow tires are a must, no matter what, but all seasons on an AWD will definitely treat you well.

[@mry82]

@@JoiceVaderd Agreed! I wish I had kept my 92 Prelude with a OE JDM LSD too... it would pull through the snow!

[@captainobvious9188]

Subaru and Mitsubishi, as well as the Classic Audi quattro longitudinal engine layout, are symmetric AWD, in that the power goes through a center differential, and then the front and rear differentials. According to my understanding the group-B Audi locked the center differential until the final evolution of it, in combination with the engine longitudinally hanging over the front axle the car had to essentially be driven like a rocket - applying a thrust vector to counter the current vector to go in the desired direction (driven sideways). Haldex systems can lock the back axle to the front and are programmed to release lock to allow turning (inherently putting most of the power to the front). Although they can be reprogrammed to just remain locked and then have to be driven like a group-B Audi. Also, you can incur a speed differential with slightly smaller diameter rear tires, whether you let some air out of them, or stretch them on some wider wheels. Then you would transmit more torque to the rear like the over-geared systems. Ford Focus RS and Honda SH-AWD (as applied to their FF platforms) are interesting in that they can independently lock each over-geared rear wheel to the front, thus they can temporarily send more power to the rear and even each rear wheel, thus able to do some serious torque vectoring. My favorite is symmetric AWD systems with modifiers that only need to operate sometimes, so it has a fundamental AWD attribute that can then be tuned and dialed right in. Subaru electro-hydraulic center locking differentials, as well as Mitsubishi EVO electro-hydraulic center and rear (AYC) differentials are this category. AYC is special in that it is a differential that can force a speed difference similar to Ford’s and Honda’s, but isn’t the fundamental part that transmits power to begin with. When not working an EVO X is still AWD, just with a rear open differential. However, when AYC is working, the car drives like a fundamentally front-engine'd symmetric-AWD car, but AYC is torque vectoring the rear (modified) from direct steering input. So it is mostly proactively driving under your control, and not reacting unlike every other system. By their very nature they can't have the clutches in a partial lock all_the_time while you're driving, so they will always be FWD with reactionary AWD/RWD characteristics. The Ford F150 Raptor is interesting in that it has an electro-hydraulic clutch as well as a hard lock in its transfer case - So it can be programmed partial torque amounts to the front axle, like the GT-R and other cars.

[@CarToneHK]

3:33 Not sure why RWD F80 M3 used to show "RWD based AWD", though the GTR R35 4 wheel drift is well cool

[@VictorEstrada]

Yeah I was gonna say

[@nathanwabre]

Editor’s little mistake I guess... but we get the point I guess

[@CrazyWeeMonkey]

Probably to show a downfall of a rwd platform car out of grip and oversteering, while the GTR is able to hold itself sideways because it has an AWD system.

[@alexandrepf8471]

@@CrazyWeeMonkey gtrs awd is rwd based

[@jryalls]

It was being used to show a RWD car.

[@HaydenStewart12]

As a 2013 Volvo r-Design driver (Haldex 5), there is a trick to a solid power slides... over inflate the rear tires, drive way too fast into a corner, give it a confident flick on entry, and shove your accelerator through the firewall. It wont hold it as long as a M3 or Mustang, but it's enough to enjoy. In the wet or on loose surface roads, you can outdrive surprisingly quick cars.

[@pawelwolski1316]

And now you have to add the Yaris GR to the "overdrive" fwd list. Don't think it's coming to the USA, but it is an awesome car with an amazing story behind it. Might be last of the kind. Really enjoy your shows, there are many car guys out there, you strike some sort of great balance. Thx.

[@30hours51]

Yea the GR four awd system is very interesting. It has overdrive and the clutch pack is constantly slipping

[@jasonchatham4170]

Cammisa makes this channel. Pay him more now!

[@jeffh7021]

Great video. This is the first one I've seen. You nailed everything. I especially like the Corvette thinking he's doing a burnout, when you're talking about clutches. Haha. Bravo.

[@bhadransnair121]

Jason Camissa is the real deal!

[@ColtCapperrune]

How is there an entire video about AWD and not a single mention of Subaru??

[@ACommenterOnYouTube]

Maybe because subaru awd is garbage or maybe because he felt it was irrelevant or maybe he is not a subaru fan ???? Let him reply ... oh wait he won't, he has more important things to do than to respond to questions and complaints by the viewers

[@ColtCapperrune]

@@ACommenterOnKZbin Subaru arguably has more all-wheel-drive cars on the road than any other single manufacturer. So it’s only logical that A video solely about all wheel drive would include Subaru. To your second point, he responds to lots of comments.

[@ACommenterOnYouTube]

@@ColtCapperrune does not matter if your logic is truth or false. Its their video, their choice to use what content they want. And i have yet to see any replies from him.

[@mikeylikesit2675]

Salty much? Did an STI cambered out vapey boi steal your gf??!

[@NitroNuggetTV]

@@ACommenterOnKZbin Calm down kid, Jesus.

[@Thelaunster]

This is the clearest and most concise explanation possible, amazing work!

[@dazone]

Every Subaru owner felt offended after watching this video :)

[@seb57220]

lol I'm a Subaru driver and it's true

[@eston911]

Agreed!! What about the only AWD worth talking about? SUBARU

[@markkitchens9833]

Yes, you slighted us Subaru owners.

[@mynameis63]

Yeah..but aren't they perpetually offended. :)

[@bokiNYC]

@@eston911 Well, it oversteers almost as much as Gold R so maybe it's good he didn't mention it...lol

[@misha8896]

Finally, somebody focusing on what's really important instead of trying to explain "the difference" between 4WD and all-wheel drive (...that does not exist, ..unless you have 6-wheeled vehicle...)

[@saimadhav9898]

1:07 Open diffs always send 50:50 regardless of conditions. The max force a tyre can apply is equal to normal force*coefficient of friction. It's not some electric current to travel in the path of least resistance. The wheel which has less traction will spin faster because it has no resistance compared to the wheel which has. It looks like all the torque has gone to the wheel with least traction but that's wrong. It still gets 50:50

[@gkky_]

I feel I'm the only person without a car that's so into Cammisa's content

[@Broyale26]

Me, too.

[@JohnDoe-xo7gg]

“While this often happens… in rental cars” 😂 best quote of the whole video!

[@alexanderspanopoulos1385]

I’ve watched every video in this series today. Can’t get enough.

[@theelmagoo]

Recently found the channel and love Jason's work so far! But... being an ex-Golf R owner and now an S3 owner, I really don't understand all the hate for the Haldex systems? I'm not disillusioned as to how much power can go to the rears, but the system definitely makes both cars handle far better than they would without them. The Golf R is a go-kart! I had mine at APR Stage 1 and it was incredible fun on any road! The S3 is most definitely not as nimble as you trade handling for comfort (*cough* weight *cough*), but it's also no slouch! And in the rain or snow, there's no question as to how much better it makes these cars behave over anything driven by 2 wheels (front or back). Also Haldex is less complex, lighter, cheaper, and provides better fuel economy than a more traditional AWD system. Yeah I can't swing the rear around, but I really don't care to do that the majority of the time I'm driving around, so it seems like a fine trade for being a daily driver with the ability to have a lot of fun when desired. And yeah, like others mentioned, please make a part 2 as there's definitely more to cover on this topic (Subaru?!?!?.... Lamborghini??!?!)

[@xgalp05]

I had cupra leon 290 frontwheel and now formentor vz with 4drive and with the formentor is I believe the biggest advantage massive traction. Leon was unable to put the power into the road even with the best tyres. Formentor is able to go all-in even in the f*cking rainstorm. The handling with 4drive feels more understeered but in the end is much more confident and enables better handling as you wrote. The cupra leon 290 had better times on track than leon 300 4drive because of weight and traction. As normal roads dont offer traction 4drive is always much better in my opinion

[@TonyBasuro]

Blip the parking brake, the rear end will come around. Then juice the throttle.

[@flounder31]

As a former Q5 owner, I endorse this video.

[@charvakkarpe]

A true know-it-all wouldn't use the terms "power" and "torque" interchangeably. This video is surprisingly correct, and covers a lot for how short it is. But I think it would be most helpful to explain that only open differentials split torque equally or 50/50, and locked differentials send equal motion to each wheel. Sending equal power to each wheel only happens when driving in a straight line with open differentials and no slipping wheels. Literally no AWD system "sends power". They only send torque or motion. If they send torque, the resulting wheel speed determines power. If they send motion, the available grip determines power. And yes, the innovation of overdriving wheels and using clutch packs to vector torque is awesome, but brings worries of clutch wear. Rear-biased or rear drive only Torsen setups are most useful, reliable, and fun in real life.

[@Jaredscott89]

Pedantic. Know your audience would be a great thing for you to learn.

[@TotallyNotASpy1]

I love the way Jason describes things. I want this guy to describe my life...

[@TheHooniverse]

SH-AWD rules and deserves more love

[@shawndejong6699]

It's a nice system, sadly it isn't on anything that develops noteworthy power or anything that could be safely tracked.

[@maxheadroom224]

@@shawndejong6699 safely autocrossed... Maybe. Enjoyed? Nope. It's a Honda it's built and designed for durability and predictability. You have to modify them to get crazy performance. S2k fanboys don't start, you've never driven one.

[@Maelstrom8]

@The Hooniverse You are so right. It is a very underrated system that works fantastically!

[@yeesenchai]

@@shawndejong6699 sadly noone bothered with it except the Spoon guy that modded the Honda Legend to demonstrate this.

[@aspecreviews]

Especially eSH-AWD...

[@hingsunhome]

Perfect description of all types of AWD system. Thank you.

[@DANNY40379]

Except the most common one lol

[@Clesarie]

Im totally fine with my FWD cars. Im not a drifty boy. I love how confidence inspiring my evo awd system is too. Its never gonna side out in any sort of unpredictable manner. If it slides its because I forced it to and even then the computer somehow just knows exactly what I want it to do and does it.

[@GrotrianSeiler]

Jason really is the best. That was an awesome explanation. You might not like what he said, but there it is. Cool.

[@jeffreysheets5312]

Informative and entertaining as always. Would love to hear your thoughts on electric AWD systems, where different motors power different axles, and compare them with the traditional AWD systems you mentioned here.

[@anthonyschroeder521]

It's both easier and not at the same time. Each motor has it's own specs, so obviously a combined load rating can't be sent to each axle. Good news is that you can choose the power limits at both axles to allow more or less whatever bias you want. Tesla's are heavily rear biased systems by default (they don't publish official numbers, but the general consensus is somewhere around 2/3 rear 1/3 front as far as motor power ratings).

[@anthonyschroeder521]

@@aspecreviewsthat was literally my third sentence....

[@cliftonsheldon9134]

The Buick Jump will forever remain a classic!

[@hurshpatel3575]

Something that wasn't addressed is something like the Subaru AWD system. More so, how would the AWD systems mentioned compare to the STI's 3 differential AWD system?

[@jsquared1013]

The STI's system is closed to the BMW/Jag system mentioned in the video, except the center diff has a static split (from 35/65 F/R to 41/59 depending on year) and the computer controls clamping the packs to change how much the center "locks" when there is a differential in speed between front and rear axle. The "problem" with the Subaru layout is that it forces the engine to be entirely in front of the front axle line (hence the short flat-4), but it does save a little bit of weight/packaging space compared to other RWD-biased AWD systems.

[@easyricer]

While stationed at Ft Campbell KY, in the 90's. My commander wanted to up grade and replace our older Hummers with the new models. While there were a few advantages to the new model there were huge disadvantages as well. The newer models had open differentials, so it really wasn't all wheel drive, it was one wheel spin! The older models had limited slip differentials. I could drop one wheel off into a deep hole, lifting the opposing wheel on the other axle all but off the ground and the two firmly planted wheels would pull us right out of that hole.

[@d-d-i]

No mention of the torsen system, eh ?

[@erictko85]

I TORSEN??????......I TORSEN!!!!!!!!

[@DuBstep115]

I would take too long, because at the beginning torsen was 50/50 then it was 40/60 etc. And now torsen is gone, Ultra Quattro has taken its place.

[@jamesmac8424]

@@DuBstep115 Torsen diff at 40/60 is still used on 4runner limiteds.

[@DuBstep115]

@@jamesmac8424 It was good system had that in my audi A5

[@bokiNYC]

@@DuBstep115 Yep, loved it in my b8 S4.

[@russphoto]

The 1986 Quantum Synchro I owned back in the day had the three position switch on the console to lock some or all of the three diffs (as you said it went straight when all were locked) but would not get stuck. It was a station wagon with a 5 speed and 5 cylinder engine with 411 rear gearing P7 tires. It was a ball to drive...........but only got about 18 mpg. Kinda wish I still had that car sometimes.......

[@lilerik58]

1 - love the Know it All series of videos! 2 - if bmw xDrive is always rwd except when it decides to send power front wards - whats up with the claim that the xDrive m340/440/40 models are "more rear biased" than the 30 series?

[@ALEX20hoc]

All i can think of is 40 models have rear e-lsd as standart

[@gattopazzo80]

Most likely refers to how the center clutch calibration was done, saying that it is more rear axle biased means that in similar driving conditions the computer on the Ms sends less power to the front in comparison to the computer of the non-M sisters

[@Wrenchen-with-Darren]

I dont know why...but I love this guy. And he's right again. That being said, I like my awd car.

[@jamiljafri4841]

THANK YOU! Finally someone said it!

[@michaelbeck3132]

Finally, someone has the guts to tell the truth. One of the biggest points here is if your car or truck has open spool diffs rather than LSD or true locking diffs, it is possible to get a front and rear wheel slipping and you basically do not move. A second takeaway is when the automaker (BMW for example) uses the Bosch brake pumping the disc to stop it from spinning but it really does not work very well. Better to have LSD. Bravo Jason.

[@williamkerry2626]

Just curious, why did you seem to specifically not address Subaru’s all wheel drive systems?

[@rodrigoalmendro3118]

He did, when he talked about the quattros

[@clux4057]

It’s the same setup as the Audi one mentioned.

[@williamkerry2626]

@@rodrigoalmendro3118 my understanding of Audi’s Quattro and Subaru’s AWD systems are different at the transmission. Kinda similar, but the viscous couplers or I should say coupling systems are quite different. Subaru uses a transmission that is quite similar to a traditional rear wheel drive unit. I’m not as versed on Audis systems, but I believe that they are quite a bit different. You and the other gentleman that commented that they are the same could be correct, but I find it odd the Subaru, who are specifically know for AWD, as is Audi, we’re not mentioned at all.

[@rodrigoalmendro3118]

@@williamkerry2626 I agree with you, but what I ment is that he adressed all permanent awd cars. Not that subarus and audi's specially that model, have the same drivetrain.

[@andrewroberti6010]

Subaru is like audi, the sti is like the sh-awd, evo, and focus rs.

[@MrGertsv]

Thank you, Jason! Just what I needed this morning with my coffee☕️

[@HamzaFaruqui]

I knew all of that before but I can still hear Jason tell me about it 57000 times over.

[@imrichkusnir824]

Such an awesome video! Thank you so much, I think so many people are missinformed on this subject.

[@Saratogan]

What about AWD v true 4x4? Would love to hear your explanation of the difference. I have a 2016 Grand Cherokee with 4x4 drive.

[@bernd2244]

The common US interpretation is, that it is a selectable AWD without a center differential. Just like the first variant described in the video. There is permanent drive to one axle and you can choose to connect the second axle in a "on/off" way without a differential. The most primitive way to do it.

[@scotth5503]

@jesuis baizuo A lot (perhaps even most) of 4x4s have an auto mode that will dynamically send power to the front when the rear is slipping.

[@coryz.872]

@@scotth5503 dynamic lol, that 4x4 auto mode is a hysteresis switch.

[@johnmohanmusic]

AWD is a vehicle with an open differential in the transfer case allowing the vehicle to drive on dry roads with all wheels being (somewhat) powered. 4WD refers to a transfer case with a closed center differential (locked) where at all times power is being sent to both the front and rear axles, meaning this setting cannot be used on dry roads. Many vehicles (including my 1998 Jeep Cherokee XJ with the optional N242 transfer case) have both settings available.

[@aynsleyjeansonne]

You don’t need to get three wheels in the air to flex 100% power to one wheel. Just move north and find patches of ice. I live in downtown Chicago and the ally behind my row house has been covered with ice patches for about a week. Urban use for crawl control on my LX 570.

[@Jastor00]

Great video! Was hoping to hear at least one mention of the Lancia Delta Integrale, a front engined car with AWD, rear TorSen differential, and a 47 front/53 rear split (on 16vs). The GOAT when it comes to 4wd rally cars.

[@BrokeWrench]

I dont know exactly how that system is designed, but it sounds like the overdriven rear axle he talked about at the end. Torsen differentials are very strong, but they have 1 downfall, if 1 wheel loses traction it will only transfer the maximum amount of torque the slipping wheel has to the other side. If 1 wheel was in the air it would transfer next to nothing to the other

[@TheDesmonaut]

Cammisa is back with a vengeance. As an extrovert who often self-sensors to "fit in" it's inspirational to see someone ExtraAF own it and stick the landing. Congrats Jason, huge fan.

[@shadmansudipto7287]

About getting out of trouble, many of these haldex type AWD systems have very small rear diffs that overheat in a few seconds and the computer turns it into full FWD until it cools down, the most spectacular examples of this are Honda CRV And Toyota RAV4. These systems are nearly useless, helpful in light snow but is it worth the extra weight? I would not choose the AWD option.

[@khalidacosta7133]

Better off fitting winter tyres instead to a FWD car.

[@dodecahedron1]

@@khalidacosta7133 you need winter tyres regardless of how many wheels are driven, AWD won't make your tires grippier in cold temperatures, change their tread pattern for one more suited for snow or make them grip on ice

[@floydblandston108]

The 'FF' Ferguson AWD system using a viscous center clutch allows for that 'under-driven' rear wheel situation in a part-time awd vehicle. Under normal driving, the vehicle drives and performs like any other FWD, but when front wheel slip occurs (open diff of course), the rising temperature in the center clutch pack engages the rear at a 50/50 torque split. The purpose of the underdriven rear is to *keep* the temp up, thereby speeding up the engagement rate. Get it right and its completely seamless and undetectable, get it wrong and every single component from the rear tires forward grinds itself into dust. Most manufacturers avoid potential problems and simply use a viscous clutch and the same ratios front and rear.

[@IvanBosnjak89]

Jason - what are your thoughts on the Mk8 Golf R and the A45 with their "Drift" modes?

[@tellyourmomisaidhi5804]

Those are the cars with the center clutch pack that slips like the Focus he showed drifting around. A temp band aid he called it. They produce heat.

[@Jaredscott89]

@@tellyourmomisaidhi5804 Everything produces heat...

[@canadianmarauder1923]

Good explanation. My 13 gmc has the awd switch on dash but I never use it. I only use 4wd when roads are covered with ice or snow.

[@coryz.872]

Lol you're shity Chevy doesn't have AWD. That mode is a hysteresis switch.

[@habeth0205]

You made a whole video on awd and managed to mention honda infinitely more than subaru. Think about that

[@smiileylalaa]

baffled .

[@Denverian]

lol

[@d1sturb3d119]

Because Honda's system was a true clutch type Torque vectoring setup as opposed to Subaru's that use brake actuated torque vectoring. The SVX had an active diff. That's about where that ended. They aren't proper AWD systems, more like brake assisted 4wd.

[@drakedbz]

@@d1sturb3d119 subaru uses an LSD center diff, nothing to do with brakes.

[@d1sturb3d119]

@@drakedbz We're not talking about the center diff. Any competent system out there has an LSD for the center diff. We're talking about the rear and front diff. The rear diff has no ability to control torque left to right. Subaru uses the brakes to control torque whereas Honda has a clutch type LSD with electronic control to split torque that gets to the rear diff 100% left to right. Hence Subaru uses brake actuated torque vectoring as opposed to active diffs that are superior.

[@gulf627]

Great video as usual. The problem is the confusion between torque and wheel speed....a modern AWD operates like a clutch based LSD...the only thing these systems do is sending wheel speed. The torque is always the result depending on the grip of each wheel.

[@pirkkaruuska5766]

Isnt the SQ5 a torsen quattro, not a haldex "quattro"?

[@rosslarkin6742]

Yes. And the Q5 isn't haldex either. It is quarrto ultra which is a different system entirely, though the basic operating principle is similar. And he left out a few more types of AWD systems. "Know it all"? I don't think so

[@juanpablohinestrosa7929]

Jason is the absolute best!

[@mrjdgibbs]

You can have a Haldex rear biased system, you just have to stick the engine in the back like a Porsche.

[@nirfz]

Yes, i remember they did build them this way for some time! (the awd Lamborghinis since they are Audi owned and the Audi R8 are the same way)

[@anonymoussoap8310]

Noob here Isn’t the RWD system also a Haldex system but it instead of the Front wheels being the ones locked to the Engine it’s the rear ones? So basically aren’t they the same just the wheels that are locked are the Rear ones not the Front ones?

[@Talynen]

​@@anonymoussoap8310 Yeah this is jus a difference between Jason using Haldex as a blanket term to describe permanently-powered front axles and the comments using it as a brand name for any of the AWD systems VAG uses based on the same principle of one permanently-powered axle.

[@nirfz]

There is a bit of a difference.1: Haldex is (or was?) a company that manufacturerd the diffclutchpacks. With that, the rear diff and the clutchpack are one unit And the axle closer to the engine is always powered. 2: Systems like X-drive, 4matic+ (and the one Jaguar uses ect): Those have their normal rear diffs (or with a LSD) and they also have a "transfer case" where the power is coming out of the gearbox a second time and via a second cardan shaft is going "back" to the front into the front diff This transfer case is basically a clutchpack that can close 0-100% and thus bring a max of 50% of the power to the front wheels. In summary the difference between a Haldex and the other partial systems is where the connection happens and what is inside the differential housing. With Haldex the connection is made "inside the differential" with the others "inside the gearbox" There are several generations of the Haldex system. The first ones were mechanically controlled and only locked when the difference in speed between the propelled and non propelled wheels exceeded a certain value. (a bit like with a torsen diff, but with clutches) The new generations are electronically controlled and so can be closed before the driven axle looses traction. (not everybody programms it that way, but it is possible) The other systems are electronically controlled from the beginning. Little sidenote: Haldex (if i am not mistaken) is a swedish company, while x-drive and most of the other of these systems, are designed and built by Magna (in Austria) by contract for the manufacturers. (Magna designes and makes awd systems for almost anyone except Suzuki, Subaru, Lada and Toyota from what i remember but they aren't very vocal about it. Those few companies do it themselves. And yes, even for Jeep they have done systems in the past. Don't know about the present)

[@YTjmn]

@@nirfz Almost all of the powertrain systems that car manufacturers use are designed and produced by someone else. They are companies like Magna, GKN, BorgWarner (who bought Haldex) and Jtekt (the Asian choice). If the car manufacturer happens to have their own transmissions, they might also have 4wd or awd systems. For example the 4Matic system from Mercedes might be their own, but I'm not sure. The original 4Matic is actually a planetary center differential that has a small lock up clutch to get you out of trouble. After you get some speed the differential works as an open differential, that might have some rwd bias. But these days 4Matic name is linked to probably half a dozen different systems.

[@matus201]

I got the 2nd gen VW Touareg. It uses Torsen diff, which is very different than haldex. No computer, it's all mechanical. Up to 80% power to rear wheels, up to 60% to front wheels. Pretty darn good!

[@snillethans]

I "belive" the urquattro system also hade a Torsen diff, but it was very balanced so it was Hard to control in the bridge between over/understeer...... Heard so from drivers.

[@shawndejong6699]

Subaru? Audi Quattro? It's quite a bit different than the group B monsters of yore.The actual torsen system and not haldex..

[@bokiNYC]

That's what I thought.

[@PapiAndrey]

Depends on the model

[@blankname8553]

The Audi he was talking about with the Porsche uses "Quattro with Ultra Technology" which is another form of a Haldex type system. It's NOT Torsen.

[@shawndejong6699]

@@blankname8553 yes I'm well aware which is why I posed the question.

[@PapiAndrey]

@@blankname8553 that’s not true, unless I misheard and he said Audi Q5. I heard him say Audi SQ5, which comes with the proper Quattro system with a mechanical center differential, it’s not haldex. The standard Q5 comes with haldex, the SQ5 does not.

[@nerva-]

The B7 Audi S4 had a Torsen center diff that sent 60% of the power to the rear wheels when there was no slip. So you got some of the rear-wheel bias benefit of the trouble-prone BMW system, while also having a kickass mechanical limited-slip.

[@dieselboy740]

Just one wheel on ground? Rock crawlers “hold my beer”

[@-redtango]

Some would argue that if you lock both front axle you will send 100% of the power to the rear on a haldex ✌ great video love Jason aka discount Sandler Camisa 😁

[@noredcr]

Interesting video. But how the heck did you do an awd video and not mention Subaru? LoL

[@CR-di1lg]

I learned it right away in my bought used off lease Volvo XC70 where the first original had driven it around in front wheel drive all the time due to a broken control. It worked much better when it was fixed and plus a 1999 XC70 can't go to the limit with the sloppy steering it has. Still loved that car and only sold it when we moved to Europe.

[@qasimalsaidi]

When I add blinker fluid to my 2006 Camry, all four wheels turn in the same direction. You're talking nonsense.

[@hajjdawood]

The user selectable 4x4 systems are the best. RWD when I want to save gas and tire wear, 4x4H when going fast but need a lot of traction (rain, snow etv), 4x4L for low speed off roading, locking diffs for very slippery situations. Can't beat it, the new ones even have 4x4A that keeps it in 2WD until slipping is detected.

[@pettersaethre]

a computer controlled system is vastly better for most people

[@RestoMog]

Skipped Subaru.

[@DuBstep115]

50/50

[@bokiNYC]

@@DuBstep115 And add understeer...(and ringlands, rev hang and crappy enteriers)

[@DuBstep115]

@@bokiNYC what is enterier, a dog breed? Terrier?

[@alangil40]

You might get the impression from this video that Audi uses a Haldex system, but Quattro systems are Torsen systems which are nominally 50/50 and can send 75% of power to either axle. if your Audi engine is mounted longitudinally then its a Torsen system, if its mounted transversely it is Haldex. I never gave much thought to this, but living in Colorado we have quite the variety of AWD systems in the family garage and driveway - two Audi Quattro cars in the family (Q7 and B7 A4 manual), a 335i M-sport Xdrive manual, a Porsche 911 C4S manual which I gather is similar to Xdrive in that it powers rear wheels first (though curiously no marketing name other than "4") and a Tesla Model S P90D - which I guess can send power anywhere anytime it wants to and apparently shifts power from front to rear as hard acceleration is in progress. Oh yeah, one lonely (but fun) RWD BMW 535i M-sport manual.