Axel & gear ratio identification

OK, I've started the resurrection of "Ol' Lazerus". First project rebuild the non-existant brakes! While I'm at it I would like to inspect and repair/replace, at least pack the wheel bearings and install new grease seals.

In one of the manuals I have (Granville King's Jeep Bible) there is an illustration of the rear axle, and an arrow pointing to the right hand differential housing axle boss, where there is supposedly some numbers to identify the axle model, as well as gear ratio.

I found such numbers on the front axle (27A 300 [or 30C?] and on the other front boss C 31377-1). So this indicates a Dana 27, but what gear ratio, can anyone help?

Is there somewhere else I should look to attempt to identify my rear axle?

Thanks,

 

Re: Axel & gear ration identification

Your rear axle (if stock) should be a Dana 44. Looking at the axle from the front looking back at it, the number will be on the upper left side web. (It is on mine anyway...).

To get your ratio: Jack up one wheel. Turn that wheel 2 revolutions and count how many times the driveshaft goes around (it might help to put a mark on it so you can tell for sure). The number you come up with is your ratio. Ex.- If it goes around about 3 3/4 times, you probably have 3.73's, if it goes around about 5 1/3 times, you've got 5.38's and so on.

 

Re: Axel & gear ration identification

O.K., I did this on the 5a (powerloc so both rear tires off the ground) and I come up with something in the range of 7.25 rotations per every two turns of the tire.

On the 6, I come up with 3.75 rotaions (3.73 I assume). What gives with the 5a?

 

With a power loc you only need to rotate the tire 1 turn.

If the above jeep is still all stock there should be a tag on the front cover to the diffs that has the gear ratio on it. it will be like 41-11 (tooth count) which divided out is 3.73

 

The tags been gone for years, which is why I tried the tire turning thing. I'll try turning just the one tire. Thanks.

 

I would just divide by two.... probably 3.73 gears

 

Yup, 3.73. Why would both tires spinning double that ratio?

 

If you want to be sure, take the cover off and look for the tooth count stamped into the edge of the ring gear. 41-11 -> 41/11 = 3.73