Topic: Gear ratio help...

[81yota4x4]

I'm trying to figure out the gear ratio on my 1981 pickup. I've Searched on here a couple times and haven't found anything, I've looked on line and found a couple people explaining how to figure it out by spinning the driveshaft and the tire so I've come up with this... My driveshaft spins about 2 1/4 times to on full turn of the tire. Am I doing something wrong or are my gears really that high? Keep in mind I have not been able to drive the truck yet as I just got it and went straight to work on building it up.

[crazymoritz97]

well i know most toy's have 4:11 gears . i know my 80 has 4:37 gears . try it one more time .

[81yota4x4 [OP]]

I have done a few times and switched sides to see if I get a different number do to the open diff but still come up with same thing

[81yota4x4 [OP]]

When I got the truck it had kickers installed on the rear leafs which I had never seen before and had no idea why they were on the truck and posted pics on here. A few people told me they were put on for axle wrap and ment for the go fast crowd so I guess it's possible who ever had the truck may have put a taller gear in it for some sort of desert race application, as I do live in Las Vegas (lots of desert racing here) that's just a pretty tall gear if I'm doing this correct. Plus the truck is sittin on about a 32" tire. I'm pretty confused with this truck...

[tgmaul88]

look at the pinion it should have some paint on the end of it, it may or may not have it but the color tells the gearing

[81yota4x4 [OP]]

Yeah I looked for that no paint

[crazymoritz97]

if it's  a high gear the it be 3:73 ?
that's the only gear that i know of the toyota make

[81yota4x4 [OP]]

well what ever it is it's to high for what I want to do with the truck so next question Ive looked for ID tags on both the front and rear eands and can not find any how can I tell what rear ends are under this truck and when I change the gears do I need to change the carrier as well, Ill be going to a 4.88 ratio

[crazymoritz97]

u are just swapping the ring and pinion. the carrier is ok .

[81yota4x4 [OP]]

Yeah and thinking of locking the front but not sure yet what locker to go with I'm on line now doing some research

[79coyotefrg]

if you jack up one side and spin the tire you have to spin the tire 2 times over since you only have one side jacked up.   if it turned 2 1/4 times then you need to spin the tire over twice.

or just raise the hood and look for a metal tag either on the inner fender or the fire wall just above the valve cover.   look for the axle code,  like G282, G102, G292 and post that.

G102 is 4.37:1   
G292 is 4.10:1

[81yota4x4 [OP]]

I looked at that tag before posting on here but the front half of the tag is unreadable. Spinning the tire twice... why would spinnimg it twice give me a different number?

[Nimyad]

When you have an open diff you spin the tire around while counting the driveshaft rotations, then multiply it by 2. So you probably have 4.37 gears. 4.56 would be another possibility but highly unlikely.

[81yota4x4 [OP]]

When you have an open diff you spin the tire around while counting the driveshaft rotations, then multiply it by 2. So you probably have 4.37 gears. 4.56 would be another possibility but highly unlikely.

Oh ok I get it thanks guys