Noise From The Rear Diff

also if he mixed up the shims and left even a tiny one out the ring gear could move side to side enough to growl whine or worse overheat or break teeth. ask him what the specs were, such as backlash bearing preload what the gear pattern looked like. so on and so forth. my money is on improper shims

Yeah, it's hard enough to diagnose something like this online when the original poster did the work himself.
We are hearing from the 'middleman' on the work, and it really is impossible to do anything more than guess.
If you had done it yourself, we could get specific answers.

I will say that I had a rear end go totally out on a vehicle, and took it to a shop to just be replaced with a junkyard rear. Well, after they couldn't find a match in the area, and had the van all tore apart, I went ahead and gave them the 'go' to rebuild the rear. The guy claimed that he had built hundreds of rears, and knew what he was doing. I bought all new parts... gears, bearings, install kit, diff, etc... He did the labor.

Needless to say, he was full of crap. He broke parts installing them, the rear made terrible noises, and after he had it in his shop several times to try and fix it (and didn't), I just got my own junkyard rear and installed it myself. I should have known when he opened the install kit and complained that there was no crush sleeve provided... The Dana 60 doesn't use a crush sleeve!

He could have messed up:
Pinion shims
Carrier shims
Crush sleeve setting (pinion bearing preload)

You could have messed up:
Break-in procedure

Also, if you have a Traction Lock diff, you need the 'friction modifier' additive along with correct oil.
The diff can make noise on turns if you use the wrong lube, or too much/too little friction modifier additive.
After a proper break-in, you MUST change the lube. The gears wear heavily on break-in, and leave all sorts of nastys in the lube.

Learn how to do a gear. It's not black magic.
I used to think it was. Now I do them myself, and was surprised how easy it is.

ratio411 said:

He could have messed up:
Pinion shims
Carrier shims
Crush sleeve setting (pinion bearing preload)

You could have messed up:
Break-in procedure

Also, if you have a Traction Lock diff, you need the 'friction modifier' additive along with correct oil.
The diff can make noise on turns if you use the wrong lube, or too much/too little friction modifier additive.
After a proper break-in, you MUST change the lube. The gears wear heavily on break-in, and leave all sorts of nastys in the lube.

Learn how to do a gear. It's not black magic.
I used to think it was. Now I do them myself, and was surprised how easy it is.

Click to expand...

I too am one who thinks it's black magic. I'd like to do my own gear but am afraid of messing it up.

There are 2 tricks to doing a gear.

1: Keep track of ALL shims.
The shim thickness that is used stock almost always works perfectly for the new gear set.
If any changes are needed, they are very slight. So just remember that whatever shims it has stock, make a great starting point.

2: After you remove your pinion bearings, take a die grinder and gently remove some of their ID. Just enough that they slip onto the new pinion gear without getting stuck. This way you can just slide the bearings on and off as you adjust pinion shim thickness. Having to press them on and off each time is a bear, plus can damage the bearings. When you are done, keep the modified pinion bearings in your tool box for future 8.8 gear changes. After you get the shims right with the modified checking bearings, you then press the new ones on.

You don't have to do this with the carrier bearings on an 8.8 as the shims are outside the bearings.

Keep the old crush sleeve too. When checking setup, you just snug the pinion nut to the old crush bearing.
Don't install the new crush sleeve until the very end, during final assembly.

Another tip... The threaded retaining pin for the cross pin, in the diff.... Be very careful with it. It can snap the head off when tightening or loosening. I opened the rear in my F150, and the head was gone from the retainer. Luckily the pin and threads stayed in place for who knows how long. I have snapped one as well... So just be careful with it. All it does is keep the cross pin from moving, nothing too taxing.

Edit:
I should mention the fact that if you are going to do this, you do need some specialty tools. A dial indicator is a must, as is a torque wrench. You should also have a way to press the bearings on and off, or at least have a shop that will do it for you.

The hardest part for me is 'reading' the paint when looking for the wear pattern. It is not real obvious as one would hope. I tried the paint on the ring at first, but putting it on the pinion and letting it transfer to the ring seemed easier to read for me anyway.

also dial-type in/lb torque wrench for pinion preload is very helpful. also a dial caliper for shim measurement