How to find axle gear ratio

Four ways to determine the ring and pinion gear ratio your axle has! Works for assembled axles in the junkyard or bare gears.
You can figure out the gear ratio of your ring and pinion in a few ways. I show multiple in the video but bottom line is your ring and pinion ratio is:
Number of ring gear teeth ÷ Number of pinion teeth = gear ratio

[@WebWheeler]

In case you didn't notice, the ratios are different because they are different axles haha. Also, when counting rotations of the pinion and tires, both tires should be spinning to get an accurate reading. If only one side is spinning (ie if you have one tire jacked up and the other planted on the ground,) the free tire spins twice as fast. That means you need to count how many rotation the pinion does in two rotations of the tire to get the estimation of the gear ratio

[@edgarparedes7985]

Holy this guy explained it so easy for anyone to understand with multiple methods . Fantastic video thank you 👍🏻

[@jamesroberts9849]

The best description on how to determine gear ratio.

[@WebWheeler]

Appreciate it! Thanks for watching 👍

[@tylerpool8916]

All the other videos talking about Multiply then divide moving decimals im like i know I don’t have to do all that great video man i gave it a thumbs up

[@Magical_Flame]

helped me figure out whats in my jeeps DANA 30 & 8.25

[@1000186ful]

Great video straight to point perfect

[@michaelcesario1158]

Saved me a lot of work with the dividing the number part thanks so much

[@WebWheeler]

Glad it helped you out! Thanks for watching 👍

[@Keriachamasii46]

Thanks for the info… that’s what was looking for 👏👏👍🏼👍🏼

[@WebWheeler]

Glad it helped! Thanks for watching 👍

[@chrisurfer83]

Excellent video!

[@WebWheeler]

Thanks for watching! 👍

[@wisamabazly]

Excellent video..thank you so much..

[@WebWheeler]

Happy to help! Thanks for watching 👍

[@stulogan9455]

Finally a video that helps

[@WebWheeler]

Glad it helps!

[@jadenhall3570]

Tysm

[@junior04292009]

Thanks for the info

[@WebWheeler]

Thanks for watching!

[@zanzolaartola]

Simple as that. Thank you.

[@WebWheeler]

Thank you for watching!

[@thaieralawadh2223]

@@WebWheeler I have 69 mustang where I want a crazy engine and transmission swap in it and upgrading the differential. Engine from 2006 Lexus 3UZ Transmission toyota R155 Do you recommend the T5 from newer mustangs differential ? From what years you would suggest to look for if I would like the limited slip as well. Thanks

[@timcarter9146]

why did you say it was most definitely a 4.10 gear ratio then count and say it was 3.7 ? so is the spin test not right lol

[@WebWheeler]

Different axles haha

[@RalphSampson...]

@@WebWheeler Holy crap! I missed that. I was wondering the same thing. Still, the turning method makes a difference as whether it is a Trac-Lok or Open differential, right?

[@charlesmarshall7122]

Could not have made it simple thanks man

[@WebWheeler]

Glad to hear it! Thanks for watching 👍

[@alifarahany3443]

Appreciate

[@TomJones0065]

Can you switch the Inner Gears from a 1/2 ton into a 3/4 ton axles, as long as its a 44 and the same ratio? GM...

[@WebWheeler]

Yeah as long as they're both GM Dana 44s the 1/2 ton and 3/4 ton use the same ring and pinion gears 👍 you will need to check the gear tooth pattern again though to account for variations in the machining of the housings

[@TomJones0065]

@@WebWheeler Ok Thanks a Bunch!!

[@jamesmacdonnell4085]

I Bought a brand new in 2010 Ford f250 super duty FX4 4 x 4 with a 6.4 L diesel engine. Will the dealer be able to know which Dana axles I have and what gears are in the differential? No one ever changed/ touched the truck. Thanks for any help_Jim

[@WebWheeler]

It will have a Dana 60 front and Sterling 10.5" rear, and yeah the dealer should be able to give you the gear ratio based on the VIN. Good luck!

[@jamesmacdonnell4085]

Thanks a bunch WebWheeler. Those Dana axles are really robust.

[@WebWheeler]

They're awesome! Super strong and easy to work on. That's why I chose them for my solid axle swap on my dakota haha

[@707SonomaComa]

Why is it written as 3.73 gear ratio but turning the pinion gear shows 4.10 gear ratio?

[@WebWheeler]

Different axles haha

[@RalphSampson...]

The difference in his example shows the mistake of having an open diff vs a Trac-Lok (posi). You can do his method with a Trac-Lok. If you have an open diff, you must keep one wheel from turning. Also, the turning and counting is not as exact as simply counting teeth. Of course, you have to take off the cover and mess with changing the oil and resealing. You should probably do that anyway, since you have never done it in that vehicle....most no body ever does it.

[@DIGGER19860]

hey, i now take my m12 die grinder to the junkyard with me

[@WebWheeler]

I just picked up one of those myself- awesome little tool 👍

[@tonycavitt9137]

Does Chevy 10 bolt have gear ratio of 3.70 ?? 10 and 37 .

[@WebWheeler]

Yeah that was a pretty common ratio for those

[@bbd4eb]

hello i broke my rear diff 3.92 dodge ram 1500 5.7 hemi 2012 4X4 I can not find same model the country where I live I found something else 3.21 My question is whether you will it work?sorry for my english!!

[@WebWheeler]

For a 4x4, the front and rear diff need to match. You need front and rear 3.21 or front and rear 3.92. Thanks for watching!

[@aceminefee6742]

Mine won’t turn is it because I don’t have a yoke on the reared

[@WebWheeler]

That can definitely make it harder. Also, some axles keep the pinion in position using the yoke and nut so there's a chance the gears aren't meshing properly with the yoke removed which would make them much harder to turn

[@guidosarducci3047]

Thank you for post. I was curious if you could run another size pinion gear with that 41 tooth ring gear? for example could use a 10 tooth or 12 tooth instead of the 11 tooth pinion gear that's already in there? It seems logical to me that only an 11 tooth pinion gear will work with that 41 tooth ring gear. So can u use a different pinion gear with that ring gear? I subbed & liked

[@WebWheeler]

Thanks for the support! Theoretically you can mesh any two gears with the correct standard tooth size as long as you get the spacing between them correct. However, in automotive applications that distance is dictated by the axle so it's not possible. Gears sets are matched for an axle based on the ring gear and pinion gear diameter, thickness of the ring gear, gear tooth size, etc. If two pinion gears are 1 tooth different (11 vs 10 teeth) they either have a different diameter or a different tooth size, both of which wouldn't let it mesh in the ring gear intended for the other pinion gear in the axle. Hope that makes sense haha. Thanks for watching!

[@guidosarducci3047]

Yes, Thank you.

[@RalphSampson...]

Okay but, by turning the pinion to turn the wheel you came up with a 4.10:1 ratio. Counting teeth is the exact method. Is the difference in the two methods because you have an open differential and you should have stopped one wheel from turning? Would that then have given you the correct ratio?

[@WebWheeler]

Different ratios because they're different axles haha. First one is a Dana 60 front, second is a sterling 10.5. You do have a good point about the tire though- if one tire is stopped, the one that spins free will spin twice as fast. So when counting pinion revolutions to estimate ratio with one tire stopped, you're ratio is how many times the pinion spins to make the tire do two rotations. But yes, counting the teeth is exact, counting rotations is just an estimate

[@zachthegamerandmusickid1237]

My grandpa sent me this lol

[@WebWheeler]

Lol thanks to your grandpa!