How do I tell gear ratio?

[Eddie94]

94 Eddie Bauer here, 4spd auto; according to my dealership brochure I have either a 3.27 or 3.73... how do I tell? If its on the door sticker that is long gone, swapped doors after accident ><

p.s. I did search first but didn't see anything

 

[MrShorty]

Door sticker is usually easiest.

Assuming it is still present, there should be a metal tag attached to one of the diff cover bolts. The 2nd line of on this diff tag starts with the gear ratio 3 73 or 3 27 (or 3L73 or 3L27 if it has the limited slip differential). Sometimes the initial 3 is under the bolt head and difficult to see.

If neither of those is available, the only other way I can think is to count rotations. Pick up the back end, rotate the rear tires through one rotation while counting how many times the driveshaft rotates.

 

[Eddie94]

Sweet, thanks for the info on the tag! Off to grab a flashlight

 

[Jason94sport]

http://www.explorerforum.com/forums/showthread.php?t=239360

 

[Eddie94]

L73! Looks like I won the rear axle lottery