how to tell what gear ratio
 

i have a 85 pickup and would like to know what axle's and gear ratio i have. can i do this with the vin number???


thanks for the advice.

Larry

Probably, but if not you can check in your driveway. jack the rear end up off the ground. put the truck in neutral. mark a spot on the drive shaft. rotate the tire one time, and see how many times your drive shaft rotates. but i am pretty sure it is a 4.10

Thats a neat trick.

Im gonna go home and try that just to see....

I assume this will work for you. Look at the sticker on the door jam and match it up with here. Since you have an 85' I'm not sure how it applies. For 96' and newer 4Runner's this page is easier to follow.

For an '85, look at the i.d. plate mounted top center of the firewall inside the engine bay. Then consult this page.

thanks again. also is it normal for my truck to me made in japan (figure since it was over hear it was made here)

I was told that if your vin# starts with "J" the truck was made in Japan.

I would be careful about going by the axle code with a truck that old. You never know if a PO has changed the gearing already.

Here is another manual way of measuring the gear ratio that doesn't require jacking. I have done it by taping a string to the drive shaft and marking the wheels where they touch the ground (bottom dead center), then drive or roll the truck one wheel revolution and count the wraps of string around the drive shaft and estimate the partal wrap. If the drive shaft spins 4 times plus about a half turn then the gear ratio is probably 4.56:1 and you have 4.56 gears. If the drive shaft spins 5 times plus about a 1/4 turn then you probably have 5.29 gears, etc...

With the one wheel method posted by 4rnr you need to multiply by 2 I think, because one wheel is not turning. I've never used that way :think:

I dont believe any multiplication is needed. although when I did it i had a locker.

That's interesting, what kind of locker was it?

If it's a 4x4, in 1985 there was only one ratio available - 4.10
(Cant say about 2wd.)
In 85, all the trucks and 4Runners were made in Japan, so that one is easy.
No multiplication is needed, locker or no.

actually in 85 if it was a automatic it had 4.30's. i have 2 85 4x4 auto for parts and they both have 4.30's. the code for 4.30's is g282 and the one for 4.10's is g292. it's rite before the tranny code. either w56 for efi or g52 for a carbed truck. that plack is in the center of the firewall above the engine like said before.

thanks I needed this

Doggone it! You are correct!
I was just chattin with my father (who was a Toyota dealer and truck nut in those days) and one of the mechanics who worked there for about 20 years and none of the three of us remembered that there were some 4.30s. Around these parts we saw very few autos until near the end of the 85 year, the dealership ordered what sold and in those days we bought Toyotas for work, hunting and fishing, etc and wanted 5 speeds, atuos just sat on the lot (yuppies weren't buying SUVs yet..) and as "enthusiasts' we paid little attention to autos (still don't.) So after all these years some details have kinda slid off to the edges....

the one i got had a snow plow on it with a auto. they must have hit a curb real bad the axle was bent and the transfer case was cracked real bad where it sticks out for where the front drive shaft attaches. when i ripped the cab off to sell the frame the floor was buckled up real bad. i think the axle shifted back so far and the tire hit the floor. when the drive shaft would not collapse any more it broke the transfer case. they but the axle back in the rite spot to sell it. the guy i got it from bought it for the bed and engine.

My truck which is an '89' was made in japan. Says it right on the door. the date and everything. I assume yours in 85 was also made in japan.

Actually, with an open diff and one tire in the air, you need to make *2* wheel revs to get *1* ring gear rotation that will result in the right number of driveshaft revs:

How to determine gear ratios

Oh, sorry about that. like i said I had a locker when i did it. To answer MT GOAT's question, it is a detroit e-z lock. I love it, very glad i didnt get the detroit locker. I am only running 32's and I have never heard of any one damaging the stock carrier. In fact after my sas i intend to run 35s on the same locker.