I was looking for a "squak-squeak" noise (u-joints I think), and I noticed alot of slop (and a leak) where the drive shaft connects to the differential. I posted a short video clip on flickr. Could someone possibly help diagnose? What's involved in the repair?
1996 F150 Supercab 4x4
http://www.flickr.com/photos/cocojen...7630776635096/

Thanks!

 

From what I could see in the video looks like its time for a rebuild. New bearings and seals at the minium. I would recommend taking it to a shop for the repairs if you've never done one before. Like the little MG by the way.

 

I was replacing the shocks on my 96 rc 4x4 when I found mine. I grabbed the drive shaft close to the differential and felt a clunk. I wound up replacing the whole rear end w/ one I found at the junk yard. I paid $50 for the rear end and bought a new trac lok off of eBay for $189.

 

At the very minimum, the pinion nut needs to be re-tightened. It's fairly common with the 8.8" axle for the nut to back off. However, if it's been that way for a long time, you might have to rebuild it and I would take it somewhere.

 

Thanks for the tips. Think I'll start at the pinion nut, and start looking for a price on a re-build. I'm not too bad with a wrench, but never been in to a diff before.
(MG's are fun too - generally more frequent repairs than the F150 though!)

 

I should have been more clear, sorry. I would take it to a shop to have them see if tightening the nut is possible. If they do it correctly, including using a crush sleeve, then they need to use an inch-pound torque wrench with the carrier removed to set the pinion bearing preload. There is also the 'close enough' method where you just hammer the pinion nut with the biggest impact wrench you can find and hope it's close. The pinion nut requires an enormous amount of torque to set. You will not be able to get it tight enough laying on your back with hand tools.

 

Ok, thanks Andy.

 

Ok, done a fair bit of reading on the subject now (makes me no expert of course).
Any way to tell if the bearings are toast? Rumble I suppose?
I'm pretty sure the seal needs to be replaced, but from what I've seen it is not a tough job. I am unable to "count threads" or mark the pinion nut orientation (so as to get the nut back exactly as it came off) since apparently the nut has backed off from where it was originally. I'm guessing that the preload is un-re-attainable at this point without installing a new crush sleeve. If the bearings are still good however, should I not just have to install the crush sleeve and adjust the pinion nut with in/lb (dial or beam type) torque wrench? Wouldn't the backlash and pinion depth stay the same with existing shims?
I haven't had a chance to look for someone to set it back up for me, and still considering the possibility of having that done if the cost doesn't send me into too deep a shock.

 

Here's what I've always done in this situation:
disconnect driveshaft.

Check for play up and down/side to side in the pinion.

If there is play try to tighten the nut to remove play. You wont be able to get it too tight by hand, the crush sleeve is pretty tough to crush.

If you still have play your bearings are bad

Remove nut and pinion flange, then pop the seal out and replace

replace flange and nut, tighten as tight as you can by hand.

Listen for rumbling, particularly one that comes and goes with throttle.

 

Sorry...post count bump.

 

Ok thanks. Won't be getting to it for a while, but will post back on progress when it happens.