Wobbly Rear Pinion...help!

[TuxRanger]

Ok so I just put a new transfer case in my 91 ranger 4x4 with new u joints on the drive shaft, but now my rear pinion is so seriously wobbly and leaking I need recommendations is it just the pinion bearing/seal, or is my whole rear end jacked up now...I know I want to put an explorer rear end so I can have discs but any say on how safe my current one is....I want to drive my truck...and I need it fixed.

 

[4x4junkie]

No, the bearings are most likely hosed (and has probably hosed the gears too).

You could take it apart and inspect everything for damage, although if you're thinking of going with an Ex rear, now's probably the time.

 

[TuxRanger]

Well I looked at it...and the pinion bolt sticking out was in there solid the yolk plate was the only thing that wobbled so I tightened it with a 1 1/6 inch socket and not I am going to try to get away with only replacing a thrust washer and the rear seal.. drives better with it tight now.

 

[MAKG]

You mean the crush sleeve?

I'd suggest checking the gear contact pattern and changing the differential oil, at a minimum. If the gears have worn or chipped so that it is riding on sharp edges, it's only a matter of time before you hear a loud BANG and get stuck.

If you changed the crush sleeve AND adjusted the preload, there is no reason it shouldn't stay put. If you just cranked it down without a new crush sleeve, it's going to back off again. If you overdid it, you'll burn up the pinion bearings.

 

[Evan]

If you have caught it early, your gears and bearings may very well be fine. I have had this happen on 2 diffs, and both times they were leaking fluid which caused me to notice the problem.

If you take the pinion locknut off and put some red loctite in it, then torque it down to 200 ft. lbs., there is a good chance you'll be fine for many years to come.

 

[MAKG]

Though note that that is a big risk. There is no torque spec on the pinion nut. There is a preload spec on the bearings. If 200 ft-lbs doesn't do that for you, it won't last.

 

[Evan]

Though note that that is a big risk. There is no torque spec on the pinion nut. There is a preload spec on the bearings. If 200 ft-lbs doesn't do that for you, it won't last.

You are wrong here.

There is a torque spec on that nut. It should be in the range of 160-200 ft. lbs. The preload on the bearing should already be set. The only way you would change the bearing preload would be if you crushed the sleeve more, and it takes between 600-800 ft. lbs. to do that.

When you set up the gears, and crush the sleeve for the first time, then there is no torque spec for the pinion nut, as the nut is torqued down until the preload is correct. That might be what you're thinking of.

 

[Evan]

You are wrong here.

There is a torque spec on that nut. It should be in the range of 160-200 ft. lbs. The preload on the bearing should already be set with the existing crush sleeve. The only way you would change the bearing preload would be if you crushed the sleeve more, and it takes between 600-800 ft. lbs. to do that.

When you set up the gears, and crush the sleeve for the first time, then there is no torque spec for the pinion nut, as the nut is torqued down until the preload is correct. That might be what you're thinking of.

If he were to put a new crush sleeve in, then simply tightening down the nut to a certain torque will not work. But chances are, all he needs to do is torque the pinion nut to spec using his existing crush sleeve.

 

[MAKG]

The only way you would change the bearing preload would be if you crushed the sleeve more, and it takes between 600-800 ft. lbs. to do that.

I suppose it might on an 8.8, but when I set up a 7.5 with a new crush sleeve, it didn't take anywhere near that much torque to crush it. I wasn't capable with the stuff I had on hand at the time of much more than 200-250 ft-lbs.

 

[4x4junkie]

It's about 300-400 to crush a new crush sleeve.

160-200ft-lbs is purely guessing where it's supposed to be. You MUST remove the carrier and check the bearing preload if you want your best chance at avoiding any problems.

 

[Evan]

It's about 300-400 to crush a new crush sleeve.

160-200ft-lbs is purely guessing where it's supposed to be. You MUST remove the carrier and check the bearing preload if you want your best chance at avoiding any problems.

Once the preload has already been set up, and you're using the existing sleeve, 160-200 is not guessing. Take a look at a Chilton.

 

[rickcdewitt]

after the pinion bearings gave up on my 91 i put a crush sleeve eliminator kit in the 8.8 so that i just torque it to spec after disassembly.
with a crush sleeve you torque it until you get the right amount of bearing drag,if you go over that you need a new sleeve.DO NOT PAY ANY ATTENTION TO THE PINION NUT TORQUE.it is the bearing drag thats important
the gears in mine were fine,you should be able to rebuild it.though if you don't have a inch pound torque wrench,dial indicator and experience DON'T MESS WITH IT.

 

[TuxRanger]

I have experience and I understand what the goal is but now that I have gone to my parts store I can not even find a crush sleeve/thrust washer.

 

[Evan]

I have experience and I understand what the goal is but now that I have gone to my parts store I can not even find a crush sleeve/thrust washer.

A crush sleeve and thrust washer are two different components, I believe. You're looking for a crush sleeve. They are often times found in the Self Help bin, oddly enough. The section that has door handles and stuff like that. Check Carquest...AFAIK they carry them.

 

[TuxRanger]

I will look in the "HELP" section next time I go to town. What does AFAIK mean??