axle id

I removed the differential cover and found these numbers on the ring gear.
10/4/77
Dana E
A3919(I think hard to read)
32957
46-13
790
Any of theses numbers tell me what is the gear ratio,Also what if I do not have the same gear ratio.

 

the 46/13 is the tooth count.. 46 on the ring, 13 pinion. Just divide the ring by the pinion. So its showing 3.53 ratio.

 

yep.

 

It's actually 3.538, round up to 3.54, a common ratio.

You MUST match ratios front and rear. Don't cross the beams - it would be bad.

 

within 10% is fine. heck, i got 4.09 and 4.11 in a rig.













R)

 

Yes, 4.09, 4.10 and 4.11 are all equivalent. When you change the ring gear diameter (ie D44 front, 14 bolt rear), there are only certain integer combinations of tooth numbers that you can make, so they pick the closest ratio. There's enough slippage off the pavement to accomodate a few percent difference.

Don't mix, say, 4.27 and 3.73, or 3.54 and 3.73, etc etc.

 

uh, kinda what i said, almost. fwiw, the 4.09 and 4.11 are in dana 44s which have the same dia. you can mix diff ratios front and rear. the key is having different moment arms (different tire radii.) as long as the effective ratios are within 10%. popular in mud drag and tractor pull rigs. for the majority of us that have the same tires front and rear, just stay in the series: 3.5*, 3.7*, 3.9*, 4.1*, 4.2*, blah blah blah.