Hey Jeep Guy

Stillrunning · #1 02-20-2009, 04:03 PM

Sorry but I forgot who here has all the know how about jeeps. A few months back I asked how hard it is to replace a rear axle seal and I'm finally getting around to doing it this weekend (truck failed inspection). I have a manual but I cannot find the torq #s for the axle nut (I think thats what its called). Do you have any idea and what is the proper way to torq this nut. Yea I just said turq this nut. Thanks for any help. Almost forgot, its a 200 Jeep Gand Cherokee 4x4 with rear disc brakes.

THEFERMANATOR · #2 02-20-2009, 04:33 PM

Sounds like your talking about the 4 stds that hold the axle bearing retainer in place. If so I believe the torque is 28 or 32 foot pounds for it. To be honest with you I never really used a torque wrench, I also winged it by bolt stretch. 28-32 should be adequite for them though as a I believe they are simpl;y 3/8" bolts.

tsubaki · #3 02-20-2009, 06:23 PM

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??

THEFERMANATOR · #4 02-21-2009, 12:04 AM

Quote:

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

.

randlemanboater · #5 02-21-2009, 07:12 AM

You learn something new every day......thanks for the lesson Ferm.

Stillrunning · #6 02-21-2009, 01:41 PM

Quote:

Originally Posted by THEFERMANATOR

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

.

Yes it is the axle seal (her car did fail inspection) and I'm getting ready to start the job. I'm not sure if this has been any help or made me more confused. I guess I'l get started and find out what I have and maybe come back and ask for some more help. I have a manual so that should help but I could not find any info about that nut which seems to be very important to have the proper torque. Thanks for the info and I might I'll probably be back looking for some more help.

Hey if any of you have those clear plastic lense covers for your headlights if they get foggy 3M makes a great kit for repairing them. I did those last night and they look like new and the kit is only $19 from auto zone. You onloy need a drill and some tape and it takes about 30 minutes to sand them down and buff them out.

Stillrunning · #7 02-21-2009, 05:32 PM

OK I now have the axle out and it was actually pretty easy and I also found the directions in the repair manual. It is the axle seal that was leaking but now I think I have to take it to a machine shop to have this compression ring removed. Unless someone knows of away to get it off. I thought about beating it off and then just replacing it but I'm worried I might tear something else up. Anyone ever done that or have a way of removing this compression ring (thats what I call it).

THEFERMANATOR · #8 02-21-2009, 06:53 PM

Quote:

Originally Posted by Stillrunning

OK I now have the axle out and it was actually pretty easy and I also found the directions in the repair manual. It is the axle seal that was leaking but now I think I have to take it to a machine shop to have this compression ring removed. Unless someone knows of away to get it off. I thought about beating it off and then just replacing it but I'm worried I might tear something else up. Anyone ever done that or have a way of removing this compression ring (thats what I call it).

The axle bearing doesn't have to come off to replace the axle seal. The axle seal is actually inside of the axle tube and rides against the axle shaft on a GRAND CHEROKEE. Look inside the axle tube about 2 inches and you'll see the seal in there. The axle bearing is lubricated via grease and has a dust seal on the shaft and an O-ring that goes around it to keep moisture and dirt out.

tsubaki · #9 02-21-2009, 06:54 PM

I'm lost.

tsubaki · #10 02-21-2009, 06:59 PM

Well FERM, not from your post, but from still's.