how can i tell my gearing?

[DustyNova]

TBH i have no clue what it is

[riz]

Make a mark on your drive shaft then lift your rear then hand turn one of the wheels one revolution and count how many revolutions of the drive shaft......... then it's simple math to figure out the ratio.

RIZ

[greg64]

As an alternative, since the diff lube probably hasn't been changed in ? years, pull the cover and count the teeth. You'll probably find that the ring gear has a ratio or teeth count stamped into the perimeter of it, as well.

[wilkin250r]

If you're lifting your wheels and rotating them to count driveshaft revolutions, there are a few small details you need to know. The way your differential works, it's designed to spin both tires (obviously). If one tire is stationary and not spinning, the other tire has to spin twice as much to compensate. So you can either spin both tires one revolution, or one tire TWO revolutions. Either method works, but one might be easier depending on what differential you have. If you have a limited slip, rotating both tires is easier. But if you have an open differential, then the single tire method is easier.

Let's pretend you have an open differential. Your method would be to jack up ONE rear tire and leave the other on the ground. Mark the driveshaft some method, and spin your rear tire exactly two full revolutions, and count the driveshaft revolutions while you do this. If the driveshaft goes around just a little over 4 complete revolutions, you likely have a 4.10. If it goes around about 3 and 3/4 revolutions, you likely have a 3.73. About three and a half revolutions is a 3.55 and so on.

Just remember, every time the differential inside your axle turns, it's turning two tires one revolution, or a single tire two revolutions, and adjust your math accordingly.