We Blew Up BOTH our Subarus Transmissions

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Both of our Subaru WRXs blew third gear, so we're going to tear apart the transmissions to figure out why.
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[@nathanaelpeterson6205]

Donut is in the past three years :”lets build awesome cars” Donut for the next three years : “lets fix the awesome cars we broke” love it

[@X88DRAGON]

Car entusiast life

[@thokim84]

How to blow $40k on a $5k car and still never be able to drive it? That is Donut.

[@courtney5796]

Cars are pain!

[@_oe_o_e_]

Content Forever!

[@bighammer3464]

Just imagine all the series you can get out of this never ending self perpetuating loop

[@MrGhost36969]

Do both! Swap one with a STI transmission and the other with a sequential one then test out what will give more bang for your buck

[@Rockerrobin]

Swapping to the sti would require new wheels because it includes the breaks and hubs. Wonder which would cost less, a used sti swap or the sequential/other.

[@ramvidot4037]

The sequential 1 will just blow up again

[@crunchysoup406]

you dont need to replace the wheels and hubs if you do a basic 6mt swap from the same generation (above 04 with above 04 transmission or vise versa really due to axel stubs) I have an 02 and to put an 07 sti in for example I could stick with all the same stuff but id need to put either axel stubs or different custom cv joints on to make it work. 02 and 07 have the same final drive so nothing in the rear is REQUIRED to be changed@@Rockerrobin

[@akidim13]

@@RockerrobinQue ?

[@Acceler2]

I feel like low car show be built stock 5 speed budget as possible while upgrading it

[@Firechicken217]

The main issue with 5 speeds is the split case design. with it having a split right down the middle instead of a solid casing like the 6 speeds, it tends to pull apart under larger torque loads and sheer the gears like this one did. thats why even with a straight cut/built gearset they will still do this more often that you would think. blast plates from moore performance are supposed to increase the case rigidity, but in my experience it does next to nothing. ive heard of some people welding the case together, but i feel like welding dirty cast metal wouldnt work either. realistically its just a bad design that was never meant to last under 200 hp let alone 300 plus. the sti 6 speeds are one of the few things that subaru did really well, but even those break 4th at about 700 on slicks, ask me how i know lol

[@gnaedigerfels]

700 hp on slicks with an awd car is insane load for a transmission/drivetrain color me impressed.

[@Firechicken217]

@@gnaedigerfels PB is a 10.47 so dont be too impressed lol, loooot of clutch slip needed to get a decent 60 foot

[@jake8215]

​@@Firechicken217dayumm that's still sick

[@BenTroxell]

If this series doesn't convince you to not mod your WRX, I don't know what will 😂😂

[@tjdaman98]

Too late, my wrx already lasted longer than all of Donuts wrxs combined

[@kyloklown9380]

they don’t know what they’re doing it’s that simple, the 5 speed in the wrx is known to be extremely fragile with any type of added power. there’s countless subaru youtube channels that never have issues like this because they know about the underlying problems with the cars and immediately solve the problem

[@drywater3559]

Donut can't even keep a Honda running...

[@jaroslavmrazek5752]

@@kyloklown9380 I agree, but tbh, what isnt fragile in a Subaru? I know more people with Subaru engine problems than all the other brands combined.

[@BenTroxell]

Yeah and it's been to the track exactly zero times.@@tjdaman98

[@Paleolithics]

I’d love to see a 6-speed swap on one car, and a sequential install on the other. Would make for a great comparison vid!

[@XD3blaze]

More likely a 6 speed in low car and a dog box in hi car. Sequentials are very, very,expensive

[@Andrice954]

Might as well just buy another car.

[@timduncan2211]

Came here to say the same. Sequential in high car. 6 speed in low car.

[@Michael_Ruiter]

I agree with this, hicar sequential and lowcar a 6 speed

[@grievuspwn4g3]

​@@Andrice954the smart option is not modding. Modding is inherently a money burn, especially with the post-dieselgate ecu crackdown.

[@mrgurulittle7000]

That “I hate tow truck drivers” quote from Jeremiah hints to the Real Mechanic Stuff episode with that creepy November tow truck guy.😂

[@687ffokcuf]

If y'all could do a sequential swap into one of them that'd be sweet!! would love to understand the process a little better when it comes to those. Thank you boys!!

[@Empire_of_Ravens]

Sequential! Sequential!

[@nothingtoseehere62357]

to keep with the spirit of hi-low, junkyard sti 6 speed for low car, sequential for high car

[@UhnkNimkm-bg8oq]

That's their third 3rd gear that broke. The first one was at the track in the episode where they compared all their upgrades

[@FUNNY02100]

Don't use big words that james won't understand.

[@EatSleepSkrrt]

Cheap vs expensive sequential

[@TopGoose-bf1mx]

Justin casually throwing an entire transmission onto the bench commands respect lol

[@jay1268]

The 5 speed is a pretty light transmission

[@King_Syd]

@@jay1268 yeah 140 lbs super easy to just toss up on a table - light work

[@Pooloeats]

@@King_Syd killer come back 😂😂😂

[@alexanderellis286]

​@King_Syd I've picked one up before it's not that bad haha.

[@HenAnt]

​@@King_Syd 140 lbs for an adult who works out or does hard labour is pretty easy. Try that same weight with a rice sack.

[@matmorkinsti]

The difference in the strength between the STI 6 speed and the WRX 5 speed is one of the greatest quandaries of automotive history. Ya’ll should do a PC on that.

[@lgmediapcsalon9440]

anyone looking to buy a wrx to mod it is ignorant. 10k more nets you the sti: more power yet underpowered but ready for more.

[@matmorkinsti]

@@lgmediapcsalon9440 modifying cars in general is a horrible idea. I put $35k into an STI and had something slightly fast than a c6 Z06. I’d rather have a bone stock Z06.

[@taxxzempt3576]

Window tint mods are a must for true performance

[@railfanatic1416]

​@@matmorkinstiI wish I could put just $35 into a car and have something faster than a Corvette /s

[@matmorkinsti]

@@railfanatic1416 typo, $35k

[@BBk20z3]

You guys should have known this was going to happen. Its pretty well known in the community that the 5 speeds are made of glass, especially when you add power to them. Im surprised it took this long tbh

[@nightkidnick]

more content

[@Sedonapass]

whats the remedy??

[@jr-a982]

They purposely do this as they ignore when other people and brands reach out to Donut to help so they can make content and corny “Subaru bad” jokes, I own a turbo Subaru and agree they’re fragile but still corny

[@jackemarleeyoung]

theyre milking these cars for every drop of content. Its good business practice.

[@brokeboycustom7655]

@@Sedonapass 6 speed from an STI

[@Clueless_Mechanic]

I've yet to own a boosted Subaru, but among the first things I've learned is that the 5 speeds are glass and you basically require the 6 speed for significant power gains. Just recently replaced the 5 speed in my Subaru

[@kristiqnzhelev4356]

You need to put ceramic plates on both sides of the trans to hold it not expand during heat and will have no problems pushing 380-400 bhp.

[@ittimjones]

So are the motors too apparently

[@Clueless_Mechanic]

@@ittimjones I've got the NA ej22 which I'm told is bullet proof and so far between my last Subaru and my current seems to be true. Sold a 97 impreza with 320,000 miles and the new owner dailies it. They've added at least 15k since

[@shatl_bar_king]

@@ittimjonesMy EJ went 127k

[@jaedonhaskins9917]

​@ittimjones they seem to be really hit or miss. All of mine have gone over 250k without problems. My buddy has an ej20 pushing 400 wheel and he can't get the damn thing to die. 287k miles on it. He's keeps saying he can't justify a new build till this one goes and it just won't die.

[@marlonrecuelo3897]

Learned a lot from this episode. I want to see you guys upgrade those transmissions. Looking forward to it.

[@danrogers9945]

Never leave comments, but being 57 years old and loving your show! Good group of guys! Thanks for the entertainment guys!

[@Nitro_Foundry]

Thanks for being a Dan, Dan! 🤠

[@vulcanizedanthony145]

as a former jiffy lube tech I can confirm that gear oil smell reaction was 100% real

[@ittimjones]

Jiffy Lube does something other than motor oil changes and tire rotations?

[@deejaythedj313]

@@ittimjonesTrans Fluid, Diff Fluids, grease any fittings you got, change head lights and lamps, wipers, fuel system cleaning, there’s a few things the oil places will do for ya. Ik at Valvoline they’d break everything down that they’ll do for you because management requires them to. I would assume it’s the same at Jiffy.

[@ILoveTinfoilHats]

​@@deejaythedj313and for only 4x the actual cost by uncertified teenagers!!

[@dirtrider88]

you shouldnt go around mentioning you worked at jiffy lube. also you werent a "tech". jiffy lube is the worst of the worst.

[@eporter5071]

​@@dirtrider88that's just what they're called, dude. Techs. This guy didn't label himself a tech, that's what they're called. Is he a school trained, certified automotive technician? No and he didn't claim to be. Stop splitting hairs, you dingus.

[@adez13]

Used to have an 01 WRX that was modded with half the parts from a scrapped UK 300 STi. Was putting out about 280-300hp. Extra power started chewing synchros. WRX gearboxes are way too brittle. Mechanic suggested swapping to a legacy gearbox as they're tougher. It handled abuse way better but there was a drop in responsiveness. The wider gear ratio was a lot nicer for daily driving though. Maybe try that in the low WRX and it'll survive better. Then only let perfect shifters drive the high WRX.

[@SonicProvocateur]

Years and years ago before I switched to Porsche, I owned a GC8 and during the bugeye years and the gen that Donut owns *everyone* on the forums called the trannies "glassboxes". Its been well known the syncros and forks are absolute trashcans for 2 decades.

[@TMTFish]

Subaru builder here. The WRX Trans has always been pretty glass. It has a terrible high torque failure as well as the diff . The 5 speed trans is referred to as the “glass trans.” The only way you can make it last a bit stronger while doing spirited driving is trying a redline cocktail mix which is basically a Redline 75w-90 mix with some Redline shockproof. Majority of the street kids and dragsters swap to 6 speed. The stock STI trans is used in various STI builds up to numbers as high as 1200whp and no failure. Specifically the 2007 trans being the best or the type RA 2019+ The gears are significantly bigger and can hold a lot more. Usually the drive shaft fails before the actual transmission. I’m not sure if in this case you just had bad luck or had bad maintenance or what, but that is unfortunate.

[@deathtoming2201]

Sadly there’s no point trying to explain to idiots 🤣 they only believe what they want to believe and that is Subarus are shit and fragile and blow up ect.

[@lightningmckurt2406]

one of the better episodes I've watched! I love the "how it broke" episodes because you learn even more than when you bolt on parts.

[@rainbowreza3523]

Do an STI trans and diff in low car, and a full sequential setup in high car. That would be a sick comparison and would fix the fragility issues in both cars!

[@jakemartinez2525]

I dont know about fixing the fragility issue haha from what I remember, both cars are still stock block. High cars engine is living on borrowed time.

[@Silentjustin06]

Yeah these engines are trash. Compared to other engines of this size or smaller. They don't make great hp for the amount of boost and blow up close to 500hp

[@rainbowreza3523]

@@jakemartinez2525 yeah that’s very true, depends on how they drive them, as long as they don’t lug these engines too much they have a chance 😂

[@rainbowreza3523]

@@Silentjustin06 yes it is quite a running joke for these things, I’ve got an STI and a “sleeper” legacy wagon, the legacy is a constant nickel and dime car at only 315 whp, but soooo fun. I’m one of the idiots that dumps a lot of money into these cars haha

[@Silentjustin06]

@@rainbowreza3523 not a idiot, if your into them than that's what you like. It's all good 👍

[@azbadfish]

"get your pitchforks ready, vape lords!" fucking killed me 🤣🤣🤣

[@lemster101]

Love to see you go through the process of doing a transmission swap with getting a bellhousing adaptor made and all that. I don't love sequential gearboxes, but it could make for an interesting video explaining the differences between gearboxes and why you would choose one over the other.

[@jeffbengtson]

You should do classic HiLo on your transmission solutions. Two different options determined by budget.

[@Raymo2u]

6 speed swap vs sequential!

[@SubieSqwad]

Definitely one of the 2. A. Sti 6 speed in low car and sequential in high car. B. PPG Straight cut gears and blast plates for low car and STI transmission for high car.

[@25rsti15]

Would be interesting to see an sti swap in one and a built up gearset with blastplates on the stock case for the other.

[@Toaasty_]

They don’t care to do anything of quality anymore. Channel has gone to shit for a while now

[@TheWhatTheGeorge]

i was thinking similar; classic hi-car lo-car

[@jackemarleeyoung]

Theyll spend more money putting a gear set in the 5 speed.

[@25rsti15]

@@jackemarleeyoung it does end up being about the same or in some cases more but there are some situations where a five speed is better suited.

[@Hakiri27]

Pretty well known that the wrx transmissions are glass, they are from a NA model car and the wrx is already pushing the trans to its limits so adding more power makes it much worse. Buy a sti if you want power.

[@drywater3559]

bruh Donut can't even keep a Honda running lol. thats saying A LOT.

[@supermakio55]

You spelled "problems" wrong 😂

[@dieselboii8537]

I’m pretty sure these are sti”s bud

[@tjdaman98]

@@dieselboii8537when did GD chassis STIs come with 5 speeds?

[@esc0bert]

@@dieselboii8537They're WRX's

[@jaredprince9732]

I've been a subaru technician for 5 years. The 5 and 6 speed split case transmission that comes in the wrx are very underbuilt and experience failures at stock power levels. The STI 6 speed transmission is actually built by Getrag, a German transmission manufacturer. Seeing the split case and the Getrag transmission side by side it is clear why I've never had to rebuild an STI transmission. It resembles the 350z transmission much more than the wrx. The gears are much thicker and clearly designed to handle some abuse.

[@t3hjnz]

"Get your pitchforks ready, vapelords!" made me laugh a lot harder than I should probably admit.

[@shiveksoi2439]

'we blew 2 trans' would have been a fire title

[@pedrojacintorodas9631]

When modding a WRX, first thing you need to do is upgrade the transmission. Stock 5 speed trans from the WRX are known to be weak and can barely handle stock power, you either swap a 6 speed sti trans or swap to forged gears.

[@quyle9483]

Or just not buy a subaru at all

[@etto3770]

@@quyle9483 idk man, i think its gonna be really hard to build a modded wrx with out buying a subaru

[@XD3blaze]

You know any companies making forged 5 speed gears these days? Kinda figured the nasioc posts from 2004 were out of date

[@quyle9483]

@XD3blaze all gears go through a forge process. And are also cryogenicaly treated. Unless you are referring to the use of 300m steel. Then that id be u aware of. Because as far as I'm concerned 300m steel is used selectively in various transmission and otherwise you'd need to special order for specialized applications.

[@quyle9483]

@XD3blaze I have seen someone out of the states making 300m gear sets. This was 2 years ago however

[@JaredRoso]

It’s designed that way because the power goes through the front differential first before it sees being split by the gearbox and sends power to the rear differential. You’re seeing smaller gears because the WRX wasn’t intended to get the “COBB” treatment because all the “race parts” were put into the “STI”. Hints the bullet proof 6-speed.

[@pancakem0lotov149]

I'm just now working on transmissions at school , this is the prefect video right to watch while on break!

[@barefootalien]

I think what I'd most like to see is two very different strategies. Low Car: rebuild in-house, maybe make upgrades when possible, if it's even possible (do they make third gears out of better materials in the aftermarket?) High Car: Install a beefier transmission, preferably sequential, including a tear-down to show the differences.

[@AlternateRye]

The 5 speed is prone to flexing due to being a split case design. Above 300 wheel horsepower it flexes, destroying itself in various ways. "Rebuilding it in house" is a terrible idea as it will just blow up again due to case flex. They recently started making anti-case flex products that you could add, but it is unclear how effective they are.

[@barefootalien]

@@AlternateRye Ah, yeah, that's not something I'd mess with either then.

[@alienclay2]

Just replace both with beefer transmissions..... And hopefully give the subi boys hope of redemption because as it stands right now, this whole hi-low series has been the perfect commercial for why not to get a WRX.

[@jackemarleeyoung]

Flatirons tuning have went over this topic and its not worth the cost to upgrade the the 5 speed compared to swapping in a 6 speed. You’ll end up spending more upgrading the 5 speed.

[@barefootalien]

@@jackemarleeyoung Cool, good to know. I had an 03 Imprezza Outback Sport a while back. I never had any issues with it, but the powertrain was stock. Probly my second-favorite car I've ever owned, with my very first car, a Suzuki Samurai, a close third. My favorite (and it wasn't even close) was a Mk2 Toyota MR2... man I loved that car. It was actually even better than the Subaru in the snow, too! It couldn't go through snow as _deep_ as the Imprezza could, of course, but it was much more controllable.

[@CDecker33]

Would love to see a high/low approach. PPG straight cut gears vs STI 6 speed?

[@inz1]

Throw both of the cars in the bin and buy 2 GT86’s.

[@sslnight]

Y’all… I love y’all and the fact that y’all are still building/working with these. Have y’all considered swapping a 6MT into both? It would be a huge upgrade. My 04 STi is still going strong.

[@SpacedAug]

This is the content i came to Donut for in the driveway. I'm happy to see it's back!

[@ascent5340]

love how you guys still make videos on ur old cars from past series its nice to see some come back for a vid every so often

[@-WhiskeyAndSteel-]

Donut was able to completely destroy the myth of how great and reliable Subarus are.

[@gulubdur]

I have been watching for a few years. This is the first time you have really torn into a transmission. Thanks for this, they seem like magic to me. I think you should do a sequential in one and rebuild in the other.

[@0GTXR]

There is an old Chevy educational video about transmissions, look it up on KZbin: Spinning Levers.

[@manz7860]

4:38 yall should get some custom Donut rollers for the boys working under the cars like that.

[@asianinashed]

Fun fact: the 6spd in the VA WRX is exactly the same as the older 5spd. The only difference is the extra gear subaru squeezed in.

[@billmehner]

This is precisely why I started watching y’all years ago! Love watching you guys wrenching on cars 😊

[@EvilCerealBoX]

WRX 5 speeds were never changed from their first introduction back in the 90s for the NA models. STI 6 speeds were a whole "new" design that is designed to handle power.

[@JoelCreates]

I blew 3rd in my 06 wrx, which also happened to the previous owner, so I replaced it (on jack stands) with a Legacy GT trans (supposedly thicker 3rd gear) and added blast plates to help counteract case flex, which (I was told) can cause poor gear meshing. It worked great, then I sold my car to a guy who gutted it for an 818 kit car.

[@kyloklown9380]

people when the fragile 5 speed that’s known to literally disintegrate with any type of added power blows up: 🤯🤯🤯

[@mikesoria3418]

was your ego equally as fragile?

[@00imprezaRS]

6 speed swap is fairly standard upgrade I think it would be cool to do a built 5 speed, straight cut gears, cryo treatment, etc.

[@darthdread1]

im a subaru owner and any modded subaru owner could tell you, dont put power through the 5 speed, the 6 speed sti box is almost essential for any more than 350hp, 400 or more its absoloutely needed

[@kettlepunch9646]

I'd love to see a video of you guys doing hybrid engines how they work and think. I know it may be a bit from left field. Plus waiting on you guys fixing a prelude

[@TimnParks]

Great. Now I'm searching craigslist for a prelude.

[@boblouis972]

I like how they’ve encountered every single failure point of the wrx, Subaru dudes just a different breed for putting up with all that crap

[@caseyronson603]

UPGRADE IS A MUST!

[@jivewig]

At this point I really want to know how much money they’ve spent on both the Subarus combined since the beginning. Even including all the ones they blew in their Hi-Lo series.

[@SubieSqwad]

Would have been a lot less if they didn't buy a bunch of questionable engines to begin with.

[@jimmybelt8616]

Yall should do a Hi Low series on tools. Yall get nice new expensive tools to help with the builds and we can see what tools are worth balling out for

[@taylorb9860]

This series simply highlights not to buy and expensive car if you want to modify it, especially if you think you can save money (without understanding the transmission&diff is the primary difference between the WRX and the STi - newsflash, get an STi if you want to put power through your Impreza

[@juicee5106]

This is some of the best content you guys have made, no bs

[@designbydoucette3318]

Takeaway: @7:05 - The Cheaper WRX platform is not designed for much more power, stop expecting it to hold up if you're shooting for the moon. It's that simple. Certainly not a Subaru problem. Solution: Send them off to ZF Design in Colorado for the best rebuilds or Subie transmission solutions outs there.

[@BoHorror]

Well said, thank you for the summary Chief.

[@omgsus]

solution: cut your losses

[@mauroghen]

It IS a subie problem that they cheap out on parts “because theyre not meant for more power” No manufacturer explicitly expects people to add more power, yet some brands over-solidify their parts regardless, simply for build Quality.

[@wayneparker2295]

Low car should get the STI 6 speed and hi car should get a sequential gearset, then you can compare them for people who want to upgrade.

[@Trasshprod]

These dudes are worse than tiktok builds. Should of been common sense to begin with.

[@AB-bx5to]

​@user-zr3fw3lk4z common sense to anybody who's actually worked with subarus. They're literally doing this from the perspective of people who haven't worked on them. Don't get what your point is.

[@Trasshprod]

​@AB-bx5to lack of basic knowledge. Lack of reading. Come on bro if you're building something, do it right. So many forums you can read that could have prevented this. That's my point.

[@AB-bx5to]

@user-zr3fw3lk4z so you mean to tell there hasn't been a single person who's had an oversight during a build? If anything, these videos showing fails are perfect. Shows that a build isn't done with just slapping on more boost/power. If you think doing it right is as easy as that, then you should really start a series on it, I'm sure you'll help a lot of people out. Not saying they didn't fuck up, just saying this is how it goes for a lot of people

[@ceilingbro]

if, if this info will help but from what my friend told me. Its because of the transmission being a split transmission and not a one piece housing like the sti. So it vibrates differently and thats why people invented blast shields for the 5speeds to help improve strength under high torque situations. Im sure theres more information somewhere else.

[@AntSwift]

I think the Donut boys have singlehandedly changed by perception of the reliability of Subaru Imprezza's 🤣

[@quyle9483]

They've always been terrible cars. Just no one cared. And subaru fans love to blanket the truth

[@AntSwift]

@quyle9483 I mean I'm more of an Evo man myself, would castrate myself to get an Evo 6

[@quyle9483]

@AntSwift I don't even hate subaru like that. It's more so these fan boys and gals lol. They are also SUPER sensitive which is hilarious. All you gotta say is something among the line "a fuckin Saturn's a better car than a pos subaru" and they'll blow a headgasket

[@AntSwift]

@@quyle9483 Who blows first, the Subbie or the Subbie fan boy? 🤔

[@dynamicunknown5899]

I feel like a good idea would be maybe rebuilding one of the 5 speeds with all upgraded gear sets for low wrx and sti 6 speed swapping high wrx so you have DCCD and compare them.

[@TheWrenchGuy]

As a Transmission Tech, I can feel that smell and headache from the burnt WRX trans. 10/10. Smelling salt.

[@Manu__R]

I think the reason why more people don't have these transmission issues is because the engine blows first 😂 My mechanic told me that my transmission would eventually fail on my 07 Legacy, it's probably the same or similar transmission as shown here. But joke's on him, it's sitting dead right now with a deleted head gasket until I have the time and space to fix it

[@KnightRowlet]

Head gasket delete so no more Head gasket issues

[@Puhnunduh]

You guys should absolutely do a sequential in high car and an sti 6 speed in low car. That would be extremely interesting to see

[@adhdturtle37]

I'm not a Subaru guy so I don't know details of your options, but I'd think y'all should be able to use those two transmissions to make a good one for low car with some upgraded internals. Then get in touch with Subara Motorsports to buy a built rally transmission for a high car price. But y'all are the ones running several of these series' so I'm sure it's been in the works for months by the time we see it ;D

[@crunchysoup406]

the 5mt upgrade isnt really worth it honestly, costs the same as an sti swap by the end of things but with the swap you get an extra gear

[@francsmash]

not really viable, they both have the same broken parts

[@Domoptik]

Sequential for Hi Car and the 6Speed for Lo Car, the next big step in the series

[@Andreasco-if6il]

“Get your pitchforks ready, vapelords” - Donut 2023

[@Nordspets]

Sequential in high car and a sti 6-speed in low, alt. A dogbox rebuild of just 2nd n 3rd . Hava a friend that had straight gears in 2nd n 3rd and that thing was pretty solid.

[@alexRamirez-yt7wc]

STI Transmissions are bomb proof yall just suck at building cars

[@kihgu]

I bet you haven’t worked on a car ever and don’t care that donut is filled with a bunch of engineers and people that have worked on a lot of cars that are reliable

[@drywater3559]

facts. Donut can't even keep a Honda running which speaks volumes.

[@knowntalker135]

​​@@kihgu you don't know what you are talking about, sti transmissions are way stronger and can hold 1000hp for a little bit

[@kihgu]

@@drywater3559 do it yourself then

[@gravyd316]

@@drywater3559 what have you built throughout your lifetime? And don't tell me that you've never made mistakes if you've ever actually built a car.

[@fredio54]

The reason it's third in a 5 speed WRX and a Miata 5 speed is bearing support location and shaft flex. Standard gears mesh properly at any engagement geometrically. But when LESS engaged they are weaker. So the more torque the more flex the less engagement the faikure is imminent. Subby 6 speeds FTW. Very nice box with built in oil pump!

[@wakeabyss]

I put PPG straight cut gears in my forester after I blew up third gear. The noise they made was awesome!

[@JLWalker101]

Fun fact the wrx transmission is weaker than the sti transmission and is only capable of holding 350 hp and about 370 tq sti transmission can hold 1000 hp and massive amounts of torque

[@nickkledis4195]

Which is well known in the subie community :) those 5 speeds are glass in comparison to the STI transmission and why an STI swap is so common on a built motor.

[@AndrewB23]

Which is why you should either build your 5 speed or put in a 6 if you plan on making power

[@kunfupandarofl]

Which is why the moment they said their cars are doing 350-400 whp on the dyno we knew this video was coming lol. It just sucks they say it’s a “Subie” transmission rather than “WRX” transmission since the WRX has always been the grocery getter and the STI the rally/race car lol

[@rogueroger0]

Tell me about it, grenaded 2 5speeda before i ponied up to getting the 6speed, the 6speed has been great

[@allanhope7018]

619 WHP in my STi for about 25k kms now. Stock trans, diffs, CV shafts and drive shaft. No issues at all. I have a competition clutch "stage 4" 6 puck single disc. It holds the power well.

[@LionRunner]

I thought the Subaru CVT is known to fail. Never thought the manual transmission would fail. As for the STi it was an absolute blast to drive. IMO it was very well priced, when I test drove it was under $40,000 in CO. Sad Subaru decide to stop it. 😥

[@ittimjones]

But the STI motor is also glass. I've known 4 owners and all 4 had bent rods from nothing more than a tune.

[@D4v1d60]

9:30 just needs some uga buga noises 🐒🐵

[@AaronSkone]

I knew from the get go you guys were gonna blow both gearboxes pushing that much power 😂 6-speed swap is a must

[@DEATHWISHVQ]

this really makes me proud to own my VQ, I don’t gotta worry about every little shit. Wanna pass 500 hp on a DE? Forge the internals, wanna make 1000 hp? No need to upgrade tranny (CD009) no need to change crankshaft etc seems like w subies you gotta upgrade everything! Not calling them unreliable but the are just under engineered engines and you’ll have to upgrade alotttttttttt.

[@slifer8910]

Mr. Subaru is gonna have a response protecting the engineers, for sure. 😁

[@PocketDrummer]

It's almost like he has substantially more knowledge about the platform than these guys... weird.

[@1up136]

My dream Hi Low would be utes! 2 xr6 turbos. Straight 6 easy power. With the budget of hi car you'd have a reliable 1000hp

[@joelkuolas4472]

the issue is with the subaru five speeds is that they're transmissions made for an NA ej20, not torquey boosted 2.5's. My suggestion (coming from a wrx and STI owner, the best 5 speed upgrade is from a factory 2007-2009 subaru Legacy GT 5 speed, or swap in a spec B 6 speed. the spec b is essentially a longer geared STI 6 speed manual,

[@zf9903]

Guys, just say “Low Rex” and “High Rex”, you don’t need to stumble over “Doubleyou Are Exx” every time lmao

[@warnabrotha95YT]

Here's a crazy idea.... Low Rex gets a sequential gearbox High Rex Gets direct drive, like in the Koenigsegg Regera.

[@phrog7420]

Hey donut, to answer your question, they make forged gears for the 5 speeds that can handle alot of HP. And it’s really cheap! I think you should rebuild the transmissions, using forged gears!

[@anydaynow01]

Using the CD009/A as a reference for what a transmission needs to be, yes! Give it to Nissan for upgrading old stuff to be great over the years, just look at that R32 to R34 evolution. That RZ34 is a great example also, only fix the things that needed upgrading. I have yet to have a CD009 fail me on track driving while running good fluids (your Redline, Schaeffer's, RP, Amsoil, not parts store swill)

[@joshunderdown8218]

Im glad this was a less sensational video, it is understandable that adding more than 150 percent of the HP rating hurts the 5 speed subie box, as it is the same basic design architecture as the 1980s Subaru manual, just with somewhat upgraded internals. Those cars were approx 70 hp...

[@TheDragunbo3]

" I Hate Tow Truck Driver's, Okay! " Jeremiah Burton 2023 09:15 😂 That's rough but also same.

[@taylerdarlas1589]

do a junk yard one in low car where the boys go and rescue it from a junk yard in the video and on high car do a nice one fresh rebuild with all supporting mods

[@NathanAshe-pumpkinpizza]

It's a mass market gearbox from a relatively small car company. The same basic design goes into imprezas, Foresters, legacies and outbacks. Of course they only built it to handle the power that they were going to put into it, no manufacturer spends more than they need to on mass market products. I don't know if the Nissan gearbox is used in other lessons or stilantis cars, but the sales volume of a 300Z would be way less than all of those combined Subaru vehicles and the markup on the 300Z is greater per car

[@Travis-7051]

In the 02-07’s, It’s well known that these transmissions can’t handle much power. The legacy transmission does a bit better, but the STI one is damned near bulletproof.

[@MXxCronicXxM_98]

I'm thinking that the helical gears possibly couldn't handle the additional torque and possibly had stress fractures to begin with. For the most part, additional power won't be that hard on it unless the driver is driving hard.

[@dirtydoge756]

This reminds me of one time I was doing disaster restoration down in the Florida Keys after the hurricanes in 2005. The boss brought his jetski along with and the other guys were on it CONSTANTLY beating the shit out of, jumping it and doing jet ski stuff. When It finally came my turn to give it a try, I got out of the private canals , gave it some throttle and the steering cable immediately broke. Natually I got blamed for it breaking because I was apparently being too hard on it when all I did was basically idle out in to the open water, give it some fuel and broke the cable. $170 later and being banned from the jetski, I now know not to ride or drive others peoples shit anymore. There is NO WAY that the steering cable broke because of anything I did, but they sure had no problem blaming me when I was literally on the thing for about 45 seconds. Lesson learned and I wont be making that mistake again. Next time I ride a jetski it's either gonna be mine, or a rental with insurance. They knew damn well that I wasn't being hard on it, but no one wanted to buy the boss a new steering cable for his jetski, so natually all fingers were pointed at me. I love that I got to spend $170 for about 45 seconds of riding on the thing, blamed for something they KNOW I didn't do, and banned from it the rest of our time down there to cover their story that I was the one that was being hard on it causing the steering cable to break. Yep, no more. Sorry bruh, but I ain't buying anything else for anyone elses jetski anymore because I'm not going to put myself in a position to where I can be blamed for something breaking. Everyone at that company were a bunch of dickheads anyways. No loss leaving that job after we were done down there.

[@marcspence1905]

“Granny shifting not double clutching like you should” “synchros”.

[@stevogaming1297]

Put a nice sequential in High Car and either a junkyard 6-speed STI or cheap/junkyard sequential in Low Car.

[@g6et_wrx177]

STI 6 speed with matching rear differential = the only option. You will find its ultimately the most economical option if it’s a known good box!

[@ouch1011]

I’m pretty sure that transmission failure was predicted by 99% of the comment section before you even installed the first mod. The 5spds are so fragile. They come from a time when most of the engines that went in front of the transmission made like 100hp. When the original clutch needed replaced on my old 06 Legacy GT (same trans) I replaced the trans with an 04 STI trans and matching rear differential. I didn’t want to worry about the transmission ever again, and 5 years and a TON of abuse later, it’s 100% fine. The STI 6spd (NOT the newer WRX 6spd) is physically much, much larger than the 5spd and more in line with the overbuilt nature and size of the 350z trans. The later WRX 6spd is tiny and fragile as well, since it’s basically just the Impreza transmission.

[@simulation993]

one with a 6spd swap and the other with a stronger 5 spd/gearset. Maybe some treatments and mods to help the 5spd? (blast plates/transmission case stiffener, Cryo treating, shot peening, whatever else)

[@GrantZaitchick]

If I'm taking all of your options seriously, consider putting a sequential in high car, and then get an STI transmission for newer Subaru. That way, you can enjoy the car you built even more, and you can get another competition and comparison video out of it.

[@americansmark]

The smarest thing Subaru and others can do is adopt the ZF 8 speed. I have the ZF in my Jeep and it is possibly the greatest automatic transmission ever. Its not as fun as a manual, but it handles power like a champ and is buttery smooth with no reliability issues whatsoever.

[@davidtran9232]

I smell a new Hi-Lo episode regarding transmissions in the future

[@poorboychevelle]

I'm 99 that this infographic for the path of power is drawn wrong at 3:00 - rotation comes in from the left, drops down to the countershaft immediately from the leftmost cog, jumps back up where the 1st gear cog is, and then straight out the back.

[@SUBARULT]

This tranamission is build by subaru in +- 1986 for 100hp engine, max 130hp on it. After that they just use same transmission with small modification. Thats why it cant handle 400hp. Meanwhile 4EAT have +- same internals as auto skyline RE4. Thats whay there are who use subaru 4EAT auto in drag race and other.

[@jr-a982]

I may be a little late on this but do low car with a STi 6speed swap as that’s what people mostly do with turbo Subarus and then just get a ZF or Samson sequential transaxle and install it in hi car

[@blsecco]

Brings back memories, heading to home depot. Granny shifting into 4th gear, not double clutching like I should. 6MT kaboom.

[@TheDragunbo3]

Everyone always told me, "Get a subaru they dont break they are the most reliable cars." Even though I remember TopGear had a poll a bunch of years ago where people voted Subaru as one of the least reliable. I've owned 3 of them, and they have been the worst cars I've ever owned. All were stock never modified, and they couldn't even handle that. So i am glad your video series on them has affirmed my experience with the brand.

[@Dudddd3]

Need to upgrade to an sti 6 speed big box the 5 speed transmission have the nick name glass gear boxes for a reason anything from the v7 up is fine and if your lucky you’ll find a dccd transmission and you can get aftermarket dccd controllers and get that 70-30 torque split could do rwd burnouts in my old Subaru basically was sick but don’t go for a super heavy clutch either when you replace the box cuz you’ll end up breaking the input shafts on the gear box done it to 2 sti boxes after launching it with a 6 puck unsprung clutch then swapped it to an exeedy super heavy duty single plate sprung clutch worked wonders had one in my old Subaru type r Sti pushing 340kw which is around 450hp and the clutch was rated for Upto 600hp never broke a transmission again after that just blew the engine twice after rebuilding it both times with full forged internals and maybe got 3-5 months out of both engines then sold it as a rolling chassis cuz I just gave up on it and bought a 13b hilux instead