Hey Jeep Guy

[THEFERMANATOR]

Originally Posted by tsubaki

FERM, (and FERM is it) he's probably talkin' about the pinion gear nut. They are usually self locking and adjustable to the needed spacing to avoid roar.
The usual way to reinstall to correct is to use a torque wrench to see how much it was to remove it and reinstall to same or count threads turned to replace to same location.
I failed at this attempt, mine roars between 58 and 63 mph.
Reason for noting original location is the gears have made a wear pattern, it's needed to get back to close where it was.

And how in the hell would any of this fail inspection??

Axle seal is on the axle shafts inside the tubes. The one your talking about is a pinion seal. An axle seal would fail inspection because it leaks differential fluid directly onto the rear brakes whereas a pinion seal just sprays underneath. And for setting the pinion torque it isn't ANYWHERE near as simple as just torquing it on most car diffs.

The pinion nut is a one time use lock-nut that holds the pinion support/yoke on. It's torque in most modern axles determines pinion rotational torque. There is a crush sleeve inside the fiff in between the 2 pinion bearings and by tightening the pinion nut it crush's the sleeve until the desired rotational torque is achieved to turn the pinion. This way the pinion is held steady under all loads. Too loose and the pinion walks up and down and wipes out the gears, too tight and the bearings will be crushed. Some diffs use a shim arrangement and all you have to do is install a new nut and torque it down. If you have a crush sleeve you have to torque it till the rotational torque is reached. If you overtighten it you MUST install a new crush sleeve and start over with the torquing.

If you replace a pinion seal you replace the pinion nut and torque it to roughly 180-225 foot pounds(depending upon differential) as most crush sleeves require roughly 200-240 foot pounds of torque with a new pinion locking nut to compress.

And yes it is FERM(actual name is FERMAN), but I let the eye getaway with THERM since this is his place and all.