FX4offroad

I have a 2002 FX4 and I know you can tell what gear ratio you have by looking at the door jamb sticker, but it appears mine was removed at some point. Is there any other way to tell?

Red-Ford

There should be a tab on the rear diff.

Ford Fan#1

well. Since it's an FX4 it has a 3.55 limited slip or a 3.73 limited slip. If the Rpms are around 1,700 going 65 then it's a 3.73

Fordfan2006

Most likely a 3:55

sam29078

http://www.fordf150.net/howto/decode.php

Red-Ford

He said his was removed at some point.

Red-Ford

Another way to tell is to take off the diff cover and count the amount of teeth on the ring, then on the pinion. When you do that you divide the amount of teeth on the ring by the amount on the pinion.

Z7What

There is a tag on the rearend too!

See that tag on the upper right?



Wayne

Z7What

Wayne

greenheadkiller98

If all else fails, jack the rear end up in neutral, turn the tire by hand 1 time, and however many complete turns the driveshaft makes, that is your ratio. IE 3:73 would be driveshaft spinning 3.73 times with one turn of the wheel