Topic: how do i find out my differential gears

[madmanweaver444]

i have a 1984 4x4 toyota truck i bought it with 33's already on it but i am not sure on the gears in the differential

how do i find out what they are

 i read several places that people with stock gearing have a hard time getting their truck into 5th gear but i have no problem with that


         thanks

[crawlerdan]

in 84 they are most likely 4:10s

unless for some odd reason its a 4spd manual, then they are 4:37s


toyota painted the pinion nut colors to indicate gear ratio, but the paint is probably not there after 25 years.


the best way is to remove the third and count teeth


you can also do the old "paint on the tire and d-shaft thing"


make a mark with a paint pen on the tire, and on the d shaft while the truck is on jackstands. then slowly rotate the tire one complete revolution. if the d shaft rotates just a hair over 4 times, you have 4:10s, if its closer to 4 and a half times, 4:37. if its over 5 times, 5:29...ect that will get you in the ballpark.


but if they are stock still-99% sure they are 4:10

[madmanweaver444 [OP]]

its a five speed but i am not sure if they are aftermarket gears so i will try the paint technique

[toyotanner]

It should be 4:10s. because 82 and on was all 4.10's unless you like special ordered different gears from the factory i think because i guess there are some out there with stock 4.56s

you can always pull your third and count the number of teeth on the ring and divide it by the number of teeth on the pinion

[OOPS]

Why would you rip it apart to find the ratios?

Jack the rear up and set it on jack stands.

Put a chalk at 12:00 on the tire and 3:00 on the d-shaft

Turn the tire one revolution; count the number of turns the d-shaft makes

4 + a little bit more = 4:10

4 + and a little past 1/4 = 4:37

4 + a little past 3/4 = 4:88

5 + and a little past 1/4 = 5:29

Do the same in the front; do not forget to lock in the hubs

If it was close enough for NASCAR and NHRA in the old days, it is good enough for me.

[Thomas P]

is there another thread around here that tells ya how many teeth are on the ring gear for what gears? you should do a search

[kneedownnate]

toyota painted the pinion nut colors to indicate gear ratio, but the paint is probably not there after 25 years

You'd think, but I've seen some beat, high mile trucks that still had bright paint there.  I'd drop the drivelines and see what color paint is there.

[toyotanner]

when i pulled out my thirds to do my 5.29s my pinions were still painted and mines a 79 it was kind of weird though because 1 pinion was like a blueish green and the other was yellow but i counted the teeth and they were both 4.37 

[DTB]

Just FYI, Toyota axle codes are NOT always 100% reliable

[madmanweaver444 [OP]]

do the back wheels have to rotate freely cuase there is some drag on my back brakes and so when i spin the one wheel forward the othere does not move, would that mess it up cuase im only getting that my gears are around 2.10 and i dont think that is right


im gonnna try the front because i am sure that the gears are the same in front and in the back and hopefully the results from the front diff will make more sense one will make some sense


thanks in advance for any help
i kinda feel

[blackdiamond]

Just roll it by hand on a flat surface with someone watching the driveshaft rotation.  Works every time.

[crawlerdan]

Just FYI, Toyota axle codes are NOT always 100% reliable

thats true...but it does vary from model to model