Topic: Rear end work

[JeepinChobot]

Okay, now that the Jeep runs again it's time to tackle the problem that existed before.

SYMPTOMS:
- My Jeep recently developed a humm which I believe to be coming from the rear diff. which is present during acceleration and maintaining speed, let off the gas or press the clutch it stops.
- Diff Fluid leaking out of the pinion seal

BACKGROUND:
- the Pin that holds the spider gears in place broke, had to replace a few internal parts (spider gears, the pin and carrier bearings which were worn due to metal fragments) which I got from a donor axle. I was fortunate that the axles didn't come out while I was driving around...

My personal DIAGNOSIS:
The pinion bearing need replacing.

My proposed SOLUTION:
- the 4WD Dana 35 Rebuild Kit for $80
- New U-joints for the drive shafts $23 each

QUESTIONS:
- Is this a plausible Diagnosis?
- Is this a reasonable solution given the Diagnosis? (money is tight otherwise I'd swap to a Dana 44 w/ disc brakes)
- Are there other parts I should replace?

[jcsanders79]

Whats a D35 rebuild kit?  Sounds like you need to check the specks on your install.   When you changed the carrier bearings did you check the gear pattern? 

[JeepinChobot]

Dana 35 Rebuild Kit: http://www.4wd.com/productdetails.aspx?partID=11653 now $109.99 (I was looking at the Holiday 07 catalog and it was $79.99)

Kit includes: inner and outer pinion bearings and races, pinion shim kit, pinion seal, pinion nut, differential carrier bearings and races, differential carrier shim kit, crush sleeve, 10 ring gear bolts, RTV gasket maker, thread locker, gear marking compound, and brush.

When I replaced the parts I matched the gear ratios in the axle, 4.11 other than that I'm not sure what you mean when you refer to gear pattern.

[jcsanders79]

Installing gears is a SKILLED mechanical opperation.  You can't just swap gears for the same ratio like a tire or what not!  You got to reset everything to factory spec. 

[aw12345]

Well the big question is did you just replace the carrier bearings and nothing else?  Or did you replace the carrier, bearings and ring and pinion from the other axle. Just replacing bearings and putting all the shims in the same place should be no problem. Even though its a booger to get the carrier in if its done correctly but without a diff spreader. If you swapped all the guts from the donor axle, then the pinion depth and preload needs to be set correctly then you check carrier bearing preload, backlash and gear contact pattern. If that's all done correctly then it should run quiet and last a long time

[JeepinChobot]

The only internals I changed were the spiders, the bearings and the pin. I reused the shims. I didn't touch the pinion or the ring gear.

A little more background on the break

When the shaft broke, the only reason I found out it broke was that I was backing out of my driveway and the Jeep stopped like i hit something, I got out and looked and there wasn't anything so I was like WTF and tried moving the Jeep again and it moved, so i went to work and then on my way home made a stop and when I went to drive away the Jeep wouldn't move, forward or reverse, then with a pop it moved. I drove home slowly, where I parked it and started checking things. I thought it could have been the parking brake to I went to pull the driver side rear tire off. I jacked it up after loosening the lugs, removed the lugs and started pulling on the tire and the entire axle came out. That's when I knew it was the diff.

When I opened it up every thing was pretty much where it was supposed to be but the shaft was broken. Upon further inspection the spiders were all chewed up and the bearings were all pitted from metal fragments. The pinion shaft has a ding in the center of it where it looks like the shaft hit it and caused me to stop in the driveway.

[aw12345]

Well in this case you could be right its possible that a pinion bearing is chewed up. can you move the pinion yoke up and dow or sideways? it should not have any play except rotational. When you turn it back and forth it will have a bit of play some in the ring and pinion and some in the spiders mo more than about 1/16 of a turn

[JeepinChobot]

the Pinion yoke does not move other than rotational at about the said 1/16 of a turn...

The leaking...

[nofearblackstar]

mine has the same leak as you last pic . so id like to know what i need to change and how to do so

not trying to thread jack you but i figured it was better then starting another

[st.chevrolet]

For the money you are going to spend to find the problem and re-build the D35, why dont you just buy a ford 8.8 rear axle from your local pick and pull

[aw12345]

all it needs is 2 bearings and races and a seal and a crush sleeve if a d35 uses one is a heck of a lot cheaper than buying a whole axle from which you do not know how badly it was abused. Check the pinion bearings and races and go from there. As long as you have a good 1/2" impact it comes apart easy

[Bounty Hunter]

For the money you are going to spend to find the problem and re-build the D35, why dont you just buy a ford 8.8 rear axle from your local pick and pull

That's be easy and cheap if he had a YJ like you and I, but he has a TJ and would have to drop a chunk on a bracket kit and possibly welding costs.  I was gonna suggest an 8.8 also as they can be found with the common jeep gear ratios.

Here's some help on changing the pinion seal. http://sija.org/bounty/Misc/D35PinionSeal.pdf