Posted by DAvid on Saturday, June 08, 2002 at 1:21AM :
In Reply to: axle ratio? posted by truck on Thursday, June 06, 2002 at 11:32PM :
Several options here: first, what KIND of axle is it? Dodge corporate (9 3/4 I believe) or Dana/spicer? If Dana/spicer with removable cover, remove it and count the teeth on ring and pinion then devide one into the other (ring count over pinion count). You can also look for the numbers stamped into the flat outer face of the ring gear like 41.11, which is a 3.73 ratio (41 ring gear teeth over the 11 pinion teeth gives you a 3.73 to 1 ratio).
On any axle, you can mark both tires at the 1/4 circumference and, using a friend to help, rotate both tires in the same direction at the same time using the 1/4 turn marks as guides and count the turns on the pinion yoke. This is fairly accurate if you know the available ratios but a 4.09, can be mistaken for a 4.10 and 4.11 for example. Chances are though, Dodge didn't have all three, just the 4.09. See how easy it is??