Pinion nut stripped?

[medic06]

Had to replace the pinion bearings on the dana 30 under front of my 01 TJ. I was attempting to torq the new nut to spec in the FSM and it stripped before the crush sleeve even collapsed enough to let the bearings seat. Am I missing something here? I'd say I got a faulty nut but went and picked up a second one and same result! I'm afraid to try a third without checking to see what I'm doing wrong. I mean so far I've been lucky and not stripped the pinion threads but don't want to push my luck. Any advice is appreciated!

 

[SteelHeadz]

That happens when there's a slight imperfection on the thread. Look at the pinion thread closely and make sure there's no burrs in them as well. You should be able to start threading the nut by hand until it gets to the locktite part then you will need to use a socket and ratchet. Once you start getting into the crush sleeve range, go a little at a time while checking the PTTR (pinion torque to rotate ) in between increments.

 

[medic06]

I'll check the threads closely then. I was beginning to wonder if I got a bad crush sleeve. The bearings never seated in the races before the nut stripped. FSM states 250 ft lbs torq then set rotational torq. But I was stripping at approx 195. And the bearings hadn't even touched. I'd like to get this done and back on the road.

 

[flatie46]

When you examine the pinion threads if you see a bad spot it the threads you may be able to repair them with a thread file. Also you may want to see if a plain nut the same thead (without loctight) will thread freely down to where it's suppose to seat.

 

[jps4jeep]

New or old pinion nuts?

New or old crush sleeve?

A pinion nut is technically a one time use. The pinion nut is a torque to yield nut and the threads will deform to set and on a second use will strip. The threads are designed for a single initial torque of 260 ft-lbs to crush the sleeve. If you are not replacing the crush sleeve and using a new pinion nut, torquing to ~180 ft-lbs is all you really need to set the pinion bearing preload. If it is a trail repair or you are re-using the crush sleeve and pinion nut, simply snugg it up good. to get you around until you can properly replace the equipment.

 

[flatie46]

Didn't know they were torque to yield.

 

[medic06]

New nut, new sleeve, new inner and outer bearings and races. Patterned gears with old nut and no crush sleeve. Pattern good. But final assembly with new sleeve and nut and resulted in three stripped new pinion nuts crush sleeve is the winner of this one I'm at a loss.

 

[medic06]

And pinion threads looked great. Cleaned them up no burrs or flattened threads.

 

[jps4jeep]

Yup, torque to yield, but 99% of the time you can re-use, especially on axles that do not use crush sleeves since you are applying way less torque.

If I read correctly, when your stripping the nuts, the crush sleeve is not compressing and your stripping at 195 ft-lbs. I would try a different source for the pinion nuts. Built a crap ton of diffs and never had the issues your listing. wondering if you just buying bad pinions nut that were not properly heat treated.

Also, I wonder if they make a crush sleeve eliminator for the D30 axle? if so, you'll only need around 120-150 ft pound to torque.

 

[medic06]

Your reading right. Nuts were oreilly's. Crush sleeve from jeep dealer. Finally just throwers the old sleeve back in with new nut and torq to 20 in lbs rotational torq. Which was close to 160 ft lbs of torq stationary. Hope it holds!