To find out the rear I have now, I can just turn the wheel and count how many times the axle spins, i.e 3 1/2 spins = 3.5 ect..? If I go to a pick and pull how can I check the junker to make sure it's good'?

 

Same issue with my 99 Cherokee with Chrysler 8.25. Narrows it down to the pumpkin but am gonna take it to the shop to have them check it out. Will let you know what it was when I find out. Can get the whole axle rebuilt for $500.00 so may just do that. We'll see... EDIT: Mechanic said Cherokees are famous for bad wheel bearings making that noise. Again, we shall see...

 

The gear ratio should be on a metal tag on the center section of the rear differential. The method you mentioned to check ballpark ratio is a good one spin the wheel one revolution and count the revolutions of the driveshaft and you then have an approximate ratio of the gears. Works the same on your or the J/Y diff.

 

Along the same topic: My 1984 has always had a nice whine from the rear end, but tonight it has morphed into a full blown howl at 55 to a nice vibration/bark/dancing bearing sound towards the right rear. Pretty sure it's the 4:10 axle (2.5L auto 904) soooooo... I imagine I am dinked unless I throw buckets of cash at it that I don't have. Anyone have a D35 4:10 laying around?

It's long since had the tag ripped off so I have no way to verify the ratio other than turn the driveshaft etc. Cannot get the cover off as some jerk stripped the torx bolts completely out before I got the Jeep. Ended up drilling the bottom of the cover a few years ago to drain it. Used a pipe plug to cap it. Works great.

I just got done redoing the floorboards, new seats, fog/driving lights and fancy woodgrain trim from an 89. This is/was going to be my winter driver too. Now what.

What are the chances that an 89 Commanche with the 2.5 will be the same ratio and would the axle fit my 84 if it is a 4:10?

 

Some Comanche stuff will interchange with an XJ but not everything. The rear axles are the same I believe but a tape measure will confirm that. The ratio tag may be on the Comanche rear end. You can confirm that ratio with the wheel spin driveshaft count method.

 

Hey blue. I called around yesterday and priced out some rear ends. I can get a spicer 35 for $125 and I found a chryco 8.25 for $250 with a year parts warranty. I know you said the spicer is a piece, but for someone who does little off-road. Simple stuff ya know. Trails to get down to fishin holes. Nothin crazy though. My question is, is the chryco worth the extra duckets? Also you said it's a direct swap. That includes brake lines, e-brake, and everything right?

 

89 either one will be a direct bolt in. yank the old one and slap the new one in and hook up everything, bleed the brakes and go.
In my opinion the Cryco is worth the extra expense but you must decide. D35s have been known to get noisey from normal use and the earlier 8.25s may work for you as well. the 27 spline axle may be an acceptable compromise. It should be cheaper and is still a bolt in but is stronger than the D35, while still not being quite up to the par of a Cryco 29 spline 8.25 axle. If you still have questions then post them up.

 

Well....

First.. Comanche.. one M.. kinda a pet peeve of ALOT of owners.
Second.. Comanche track width is identical to that of Cherokee.
Third(and the one that you are going to dislike)... Cherokee Spring over rear axle. Comanche Spring under rear axle. You would have to remove the perches and remount them on the top of the axle to make it work.

Spending the effort to fix a D-35 is kinda like repainting your old rig right before the wrecking yard picks it up.

But the gear ratio selections for D-35 equipped Comanches are the same as D-35 equipped Cherokees.

 

I was looking around again today for a new rear axle and I found a spicer 44 for $175. Blue what's this and the difference between the chryco 8 1/4? Would it be a direct swap like the cryco?

 

Yes it is an excellent much sought after rear end. Worth that and then some. ****** it up quick.