jakeduece

You mean move them by hand? I had the jeep on stands and ran it in gear so I could watch, nothing seemed out of the ordinary, even at 35mph (where the sound is loudest usually) I didn't hear anything bad. Yeah I used brake cleaner and cleaned the heck out of it. Everything felt tight, even the yoke only ha enough play to hear a faint click when really tugged on. I could however see the pinion gear move when it clicked. So I assume that means it's the pinion bearing.

builtnotbought89'

Ya if your pinion gear moves side to side at all means the pinion bearing is shot! But a little bit of play in rotation of the pinion to ring gear is normal backlash.

jakeduece

Ok looks like it's time to start hitting the jy's. Should I replace the whole rear end? Or is just changing the differential itself easy enough? Would a Dana 35 (etc) be a plug and play (so to speak) as long as it's a 3.55 ratio?

MountainMan2071

The chocolate milk looking fluid, is usually an indicator of water in the fluid. I would clean it out as best you can with carb or brake cleaner. Then add new fluid, drive 100-200 miles, and then change fluid again.

Normally a whine noise on accelleration only, is an indicator of gear problems. If it were the bearing, it would most likely make the noise on acceleration and coast. Gear whine is normally not dangerous, just anoying. Some new fluid may help the noise. Especially since yours was watered down.

I would try new fluid before spending any $$$$$$$$$

builtnotbought89'

He has play in the pinion bearing!!! thats far beond an annoying whine! If it has play side to side it could cause the pinion to crash with the ring gear, locking the axle. he already said theres a chip in a pinion tooth!

Jake,

It isnt easy to swap out the pinion bearing on the 8.25, so replacing the axle is your cheapest bet. I wouldnt swap a D35 in if you do or plan on doing any hard wheeing. If the jeep is just to get you from piont A to B then ya the D35 w/3.55 is a plug-n-play!

good luck man

MountainMan2071

Actually what he said was "not much play at all"!!!!!!!!!!!!!!!!!! If the noise go's away on coast, it is not likely the pinion bearing.

builtnotbought89'

Sounds like a good plan... let is ride! Haha

Jake pm me if you want further info

jakeduece

the pinion has play in it, but I can't see the actual play, I can only feel it, that's how minuscule it is. The gear has a chip in it, in the very end of the tooth. Id like to drive it as long as I can, but obviously if the axle could lock then I don't want to take that risk. If it's the gears, I will keep driving it. When I changed the fluid I used brake cleaner and sprayed out the differential 3 times, just to make sure it was squeaky clean! I will limit my driving to local only until I either get a new differential, or confirm it's only gear noise and isn't as dangerous as originally thought. Thanks guys!

Flash1034

My guess is pinion nut is loose. Check that before you do anything.

Flash

builtnotbought89'

Oh well if there is no play in the pinion, then run it for a while avoiding high speeds, then replace the oil again in a week or 2 like mtnman said! If its just a bearing whine from the water that got in there it should quiet up as the residue wears off the bearing(s) I would check the pattern next time you open the diff!

jakeduece

Ok will do! I'll try again to tighten the pinion nut, just to be sure I can rule that out. I have to drive it 100 miles in 2 weeks to meet family, so I might stick to county roads instead of the interstate haha

jakeduece

Tried tightening the pinion nut, I gave that wrench everything I had and not a budge. I think it's tight haha. I will change it in a week or two (the fluid) and let ya guys know.

jakeduece

Ok guys out of curiosity I felt the pinion on the front differential and compared it to the pinion on the rare differential, and I realized what a pinion should feel like. Anyways, I need a new pinion bearing. I will let ya know when I switch out my differential, because I'm gonna dig through the old one when it's out, just to see what all is wrong. Because my axle bearings feel loose too. I can move the wheels in and out slightly.

builtnotbought89'

Glad to here your taking care of this! Most people would let it ride tell there diff grenaded out from under the jeep! Haha

jakeduece

Yeah I definitely can't let it go unnoticed, especially to the point of detonation haha! The jeeps my baby, and as such I will dedicate my blood sweat and tears (lol) into making sure it runs like a top! I will keep y'all updated!