Rear Gear Ratio Explained

[@cheekydemon6131]

You should teach children at school. I already know how this works, but I watched anyways. Not everyone has the gift to convey knowledge to others in a way that's 100% clear 😀

[@DustorBust]

Hi Cheeky Demon! This comment really means a lot to me. My content kind of bounces around, but I have been thinking of doing more like this. I really appreciate the kind words!! Thank You! 😀

[@radiow4qa71]

Excellent, clear, no non-sense explanation. KZbinrs: do more like this!

[@superdiver.]

This is gold, and should be highly recommended to all car enthusiasts.

[@DustorBust]

Thanks Spy See!!

[@chiplebeau5768]

I came here looking for slightly different info and got better info than expected! Thanks for explaining on the spreadsheet as well! That was a nice touch, great video sir.

[@MikeMMartinIII]

Very best explanation I've heard in 50 years . Great video man .

[@zacchaeusstephens6164]

I can honestly say I learned something today !!! Thanks a lot!!!

[@DustorBust]

Awesome, thanks for watching!

[@BEACHYz]

Right.. same here

[@chrismclain8769]

Same here

[@Coolshizeveryday]

This is the best video I’ve ever watched all the way through. Fantastic content. Thank you for taking the time to make this for us.

[@DustorBust]

Hi Alex, thanks so much for the comment! I am very glad you found the video useful. 😀

[@MYasir-wh4uj]

I just wathced it, it was like exactly knowing the fact that I was wandering for weeks... So incredible.. and I found out this video so much effective for my need.. Thanks a lot for doing this!!! 💯💯💯

[@robertharris3534]

Thanks for keeping it simple and not to the extreme like all the other guys

[@DustorBust]

Thanks!

[@ThomasAtkins-bw7lo]

👍👍Excellent demo and info. Couldn't be explained better 👍👍👍

[@evanmakopoulos8527]

I'm in this position right now. Thanks for the video.

[@ShellShockerSporanox]

The Excel segment was really well done, especially with the goal seek. Thanks!

[@DustorBust]

Thanks for the comment! Glad it was helpful!😀

[@BEACHYz]

Dude. You really know how to teach. Super impressive thnx for the lesson. I would have like to see some options with smaller or larger tires. Super cool man. Thank you

[@MrSam500]

Yep, loved your explanation style. I fully understand rear end gear ratios now. Thanx!

[@DustorBust]

Awesome, thank you for the comment!! Glad it was helpful! 😁

[@c.a.r.s.carsandrelevantspecs]

Great examples! Thanks for presenting this helpful info!

[@MuscleCityMadness]

Amazing Info wow.....this opened my eyes to putting a 4.10 vs a 3.55 in my car. I currently have a 3.23 in it. Now i see why they say a 4.10 is really for the 1/8th mile racing as you'd never make it down the 1/4 mile without maxing/topping out your top speed and then the guy next to you would blow by you on the big end with his 3.55 rear end car

[@DustorBust]

Hey Ruben, thanks! Glad you found it useful, this one was a bit down in the details. Yeah, huge impacts form gearing. At some point I will have to change out my Granny gear 2.94's. 😀

[@marcnesbitt3423]

Actually a really good explanation. Thanks from Australia

[@ArindursForge]

Holy cow this is a fantastic tutorial. Thank you very much

[@joebeezy9471]

An intelligent man will speak clearly and in a way that allows the majority of people to understand. This is because he is confident in his abilities and welcomes questions. A man who knows little about what he is talking about will use big words and field specific jargon. This is because he has no confidence in his knowledge and hopes to make others feel inferior in the hopes they will not ask questions. When and if they do he will mock them.

[@bush600r2]

Excellent explanation. Well done thanks

[@TomiHarley]

Thank you for this video it helped a lot, I really appreciate that.

[@averagejoe8213]

Awesome video!! I can always appreciate a good spreadsheet!

[@scottishlyscubaru145]

Nice car back there. I have one myself. Great explanation

[@tailsfromthejunkyard1023]

Hey man I’m a new subscriber and I just wanted to say you have awesome informative content and keep up the great work. I love the build and I love the channel. I will be following closely. 👍

[@DustorBust]

Thanks!! I appreciate that😁. Just saw your channel and subscribed. Good luck on your projects & channel!

[@tailsfromthejunkyard1023]

@@DustorBust thank you so much

[@CloverKCBC]

Excellent presentation! Thanks.

[@DustorBust]

Hey Austin, thanks for the comment!

[@rkroz4005]

Great explanation and the spreadsheet data analysis was very helpful. Thanks for taking the time to share your knowledge!

[@DustorBust]

Thanks for watching! Glad it was helpful. 😀

[@clipvue222]

Awesome video. I have a 1986 dodge ram d350 and was looking for a way to get it more mph so I can drive it on the high way. So now I know I need a lower gear ratio

[@DustorBust]

D350 is a lot of truck 😀, love the body style on those. Glad the video was helpful. Good luck! 👍

[@GreyRockOne]

Thanks! Very detailed explanation, I vaguely knew about why and how on ratios but not anymore! BTW, Love the 74 Duster 360, love the color and my favorite engine is the 360, You'll keep it all original?

[@sonniestrong5598]

That bicycle demo was very helpful

[@DustorBust]

Glad it helped, thanks for checking out the channel!

[@craigmonteforte1478]

thanks for the lesson, i’ve had several Antique British Sports Cars more Specifically MG T Series cars i know you will laugh but back in the 50s they were extremely Competitive Race Cars despite only having 4 Cylinder Cars they Competed and won very often the Cars were Factory built and designed to Race they ven had a Wooden Floor over the Rear Pumpkin that Pit Crews could change the gearing very quickly during a race without needing to drop the rear Axle or get under the Car they did everything from the top and didn’t even have to drain the fluid honestly i always thought that was very cool as i learned about that from my Father who as a Teenager loved watching those Cars Compete on Dirt Tracks another smallTid Bit the originalMGs actually were Americans introduction into 2 seater Sports Cars and that’s what inspired the Corvette and Thunderbirds in the 50s the Bucket Seats ,Low Center Of Gravity , Convertible , and great handling ! Of Course Americans added the HorsePower because of the V8 engines we had developed , my Personal Truck is a Chevy Dually 4X4 Turbo Diesel and i wish that one had a simpler way to Swap the gearing out but it doesn’t and because i do tow heavy weight Inordered the Truck with410 gearing based on Chevys Conservetive Bullshit on the FuelEconomy of their 6.5 Turbo Deisel that year now it will pull a house but she drinks her fuelespecially if i want to Tow at anything over 55MPH which i do prefer FYI i do not have my own Lift or Pit to work on this Truck right now so doing the gears myself is going to be a royal PainInThe Ass untill that changes ?

[@DustorBust]

Hi Craig, thanks for the comment. 60s MG racing sounds awesome!! I wish mine were as easy to change also. Those race guys find cool tricks. Thanks for checking out the channel!

[@armandosanchez3885]

Nice, I forgot about that overdrive option. Let us know how that turns out

[@Randy_51_]

Thank you for this explanation!

[@Chris-ut6eq]

Thanks for posting, very helpful!

[@33juiced]

Quick question. I currently have a67 camaro with s350 and 4 speed tranny. It doesn't like to go past 70mph it runs on high rpm. Any suggestions on how to fix that? Recommendations on a rear end and ratio? Thank you

[@DustorBust]

Hi Juiced78! It depends what you want the car to do. If you want a highway cruiser then you might want something like a 2.7-3 ratio. If you know your trans gear ratios and your engine rpm at 70 you can estimate what you have with the calculation in the video or there are some online calculators. If you have a 4 speed and still are high rpm at 70, then your gears are probably pretty short/ or a high ratio for acceleration. You might also look at tire size. A taller tire gives you more speed per rotation, so that can help get your revs down a bit also. Good luck!!👍

[@33juiced]

@@DustorBust I'm planning on testing the ratio on my rear end. I don't see s tag. I'm just wanting like a cruiser for the highway. But I will definitely be looking for 2.7 -3. I really appreciate your input buddy. Thank you

[@harleyguy932]

Great explanation

[@TheHansoost]

Well done. Even I understood most of this.

[@chiragsomaraj5121]

hello sir, you can use the handle of a used tooth brush to point out areas your finger cant reach..

[@DustorBust]

Yes, I will keep that in mind for next time. Thanks for watching!

[@EYE_SPIDER]

Very helpful video!!!

[@DustorBust]

Glad it was helpful, thanks for watching!!

[@Mrcc893]

Thanks man! Now I understand it!

[@PeterRoos]

Excellent and crystal clear explanation! Thanks.

[@DustorBust]

Thanks Peter!

[@alienUAE]

Thank you very much for this video. Now I understand the gear ratios. You got a new subscriber!

[@DustorBust]

Hi, thanks for subscribing. Glad it was helpful!

[@theitineranthistorian2024]

good video, keep them coming.

[@jkkpbs]

Great explanation! Very helpful!

[@sedem911]

Thanks for this video. A lot of education for me. I have a 97 290GD (G Wagon). I changed the engine from a 5 cylinder diesel to the famous OM606 engine and transmission. Do I need to change the axle ratios to be able to at least get 150km/h high speed?

[@DustorBust]

@Mathias Kumahor , thanks for checking out the channel! Sorry, I am not familiar with those cars or the specs, but you could easily calculate it if you lookup the trans specs. Most cars can easily hit 150km. For me this is an issue because of the 3 speed transmission, I just run out of gears quickly.

[@landonbrown8482]

I have a 1979 Volare with a 8 1/8 diff and a 2.90 ratio. Wanting to change it to 2.76. Only thing I’m wondering is are they interchangeable? I don’t want to buy the gears and they don’t fit onto the case.

[@DustorBust]

Hi Landon, sorry I am not familiar with 8 1/8. Are you sure it is not 8 1/4? They made lots of those. Good luck with your gear swap!

[@donotedit4646]

Question! I bought an 89 ranger that has been converted from an automatic to a standard shift. I’m not sure of the gear ratio but its very high. it’s very difficult to pull out on hills and etc. do you have anything to recommend? I’m more interested in pulling out and or crawling in 1st gear.

[@DustorBust]

Here is a good article on crawl ratio, basically a bigger gear ratio 4:1, 5:1 would be better for crawling and will also help your acceleration. Good luck 👍 shiftsst.com/blog/post/off-road-gearing-%E2%80%93-simplified.html#:~:text=50%2D60s%20Crawl%20Ratio%20%E2%80%93%20Backroads,constant%20throttle%20to%20avoid%20stalling.

[@donotedit4646]

@@DustorBust Thank you so much!!

[@ricksmith6735]

Great video!

[@DustorBust]

Thanks Rick!!

[@ActiveDadsRule]

Immediate subscribe… I need this excel formula for my 350 turbo transmission, I have 24 inch rims and my engine tops out at 6500 rpm. I have a street truck with posi 373 gears now. Thanks

[@y0ungtchalla420]

Mind sharing this spreadsheet ?

[@taylorpinkney7253]

Love this video very much

[@DustorBust]

Thanks Taylor!!

[@dreamingcode]

Very helpful!

[@kotoucek89]

Excellent magic with excell :)

[@DustorBust]

Love Excell 😂! Thanks for watching.

[@yudamalka8572]

What do you mean when you say power over top speed? Like torque or… would you mind explaining?

[@DustorBust]

@Yuda Malka Yes, I should have said torque, that would be the better term to use. Thanks for watching!

[@derekball5052]

Can you share that spreadsheet?

[@DustorBust]

Hi Derek, Thanks for watching! Sorry I lost track of the sheet, but I do share the formula in the video to help you recreate it. Good luck!!

[@marioandultrachap]

Ok so If your doing a turbo build I'm guessing the bigger gear ratio is better for the street for better acceleration and low end torque. While if your doing a drag application it's the opposite Low end speed is better since your starting off the line at a high RPM. Im guessing maybe it's the other way around if I'm wrong let me know lol

[@DustorBust]

Hi, good question. Let's start with non turbo. Street cars have a lower ratio, or taller gears like my 2.94, this provides lower torque multiplier, but allows for higher top speed for cruising the highway. Drag cars, have higher ratios or shorter gears. It depends on multiple factors, but people racing 1/8 mile will usually have a 4.0-5.0+ gear ratio, maximum acceleration with low top speed. They run out of truck. 1/4 mile is more complicated. The turbo is just a torque multiplier, when under boost. The speed relationship if each gear and top speed will not change. It also depends heavily on transmission. My daily driver is a Subaru WRX, it comes stock with 4.10 gears for good acceleration, but it also has a six speed trans, so it performs just fine on street and highway. Hopefully that helps! Thanks for checking out the channel.👍

[@marioandultrachap]

@@DustorBust so the higher ratio won't allow my turbo to spool faster which would be better take off on the street. I get the tranny makes a big difference but this just a general sense we can assume the transmission is the same either way and you just want to change out the rear end. Would a somewhat bigger ratio make my car take off faster vs a small ratio if it gives you more torque?

[@DustorBust]

@@marioandultrachap ok, I see what you are saying. Since it will rev faster does that also help get into boost faster. It will already accelerate faster, but will it get an added bonus from the turbo. I honestly don't know. Interesting thought. A turbo tuner would probably be able to help with that one. Sorry, that one is beyond me. Good luck!

[@thenobody5314]

How does hp factor into this?

[@barrykilts4506]

A better way to explain this from where you count the teeth is to have 3 tires all different heights next to each other and roll them all showing how far each goes to make 1 revolution.

[@thebigone6298]

Thank you sir.. ❤

[@DustorBust]

Thanks for watching!!!

[@professorgreen1215]

5,500×2.45×2.94×24.5 = 970,604.25 How do you end up with 55.654?

[@chiragsomaraj5121]

also sir differential ratio is constant while gearbox ratio changes right?

[@DustorBust]

That's right, your rear ratio is fixed based on the teeth of the gears and you only have one set. The transmission or gearbox will shift between it's own sets but still must use whatever gear ratio you have in the rear axle for the total ratio.

[@djtoutdoors3930]

Good video!! Thankyou!!

[@DustorBust]

Thanks for watching!

[@vincentgately2843]

Dude looks like Shia Laneouf...anyway great video man thanks...👍👍👍

[@DustorBust]

Lol 😂. Thanks for watching!!

[@UnfamousRT]

🔥

[@TheTruth-fb4be]

GOOD!

[@Imjoe159]

❤

[@garyv2196]

Basically, the pinion gear turns 4.10 times to 1 tire rotation. done.

[@limplin7]

7:27 It gives you more torque NOT more power. Power depends on the engine not the differential or gearbox.

[@DustorBust]

@limplin7 you are correct. Saying torque would have been more accurate. The engine will dictate the amount of available work/power. Gearing will determine where in the rpm range it is used . More torque will give you faster acceleration, but with the change in rpm the actual power calculation will be the same. Feels like more "power", but is really more torque. Good call-out.

[@zvonimirskvorc3006]

So supercars just have 8 or 9 or even 10 gears so they can acelerate quicker and have higher top speed with the same rear end? Honestly I would like to have a little bit of both some day when I buy myself my own car, my dream is to build a dodge demon or some older muscle car that will be able of going fast and quick not just one of these two.

[@DustorBust]

That's right, new supercars have lots of gears. Hellcats have 8 gears. F1 cars also have 8 forward gears and that is how they have the best of both worlds. There are some drop in 6 speed transmissions that work with older muscle cars. Anything is possible, but sadly often budget dependent. Thanks for checking out the channel!

[@professorgreen1215]

I multiply all number in the first row and I end up with total different number

[@brianwil89]

Not sure that your going to be able to find a street/ strip type rear tire thats 24.5 inches tall. 26 or 28 inch is more like what you will find.

[@DustorBust]

Excellent point. With the stock 14" wheels the tire options are very limited. I used what I have/stock setup for the explanation, but eventually I do want to update the wheels and tires and this will for sure impact the speed/torque relationship. Thanks for calling that out.

[@frankloewen3191]

Could I contact you somehow ? I’m doing the same project but I’m not that far get due to some doubts I’m having I don’t know if maybe you could help me out?!

[@DustorBust]

Hi Frank, I am still an amateur but am happy to help however I can. Send me an email at [e-mail] and we can exchange contact info.

[@frankloewen3191]

@@DustorBust thank you

[@sonniestrong5598]

I’m smarter now

[@musclebone7875]

3.36 rear gears for me

[@DustorBust]

Nice, that is a good balance. Good power and still can cruise the interstate. 👍

[@musclebone7875]

@@DustorBust yes, plus I have a gear vendors overdrive. 2,100 rpms @ 60mph 👍

[@mmb1487]

Great video thank you

[@chham57]

Great Video!