How to figure out what gear ratio I have

[Bowhunt78]

I just bought a 92 2.5l w/manual tran and 33's. Short of going to a shop how can i tell what gears are in it. the tags are missing and the saleman didnt know if the previous owner had swapped them out.

 

[Bounty__Hunter]

4.10 is the stock ratio. If you can't use 5th gear much, it's likely stock.

If the jeep is new to you, best bet is to pull the diff covers to change the gear oil, and pull the numbers off the outside of the ring gear. Then divide the large 2 digit number by the small and you will have your gear ratio. These are the tooth counts of the ring gear and pinion gear.

 

[DREDnot]

The driveway check is to put a mark on the driveshaft you can see from the side, and a mark on the tire where it touches the ground.
Roll the jeep,in neutral, by hand, one revolution of the tire and count how many times the driveshaft rotates.
Four revolutions and a little more is stock for the 2.5L