Axle bearings wearing out

[Ralph]

I'm just curious if anyone else has experienced problems with their rear axle bearings.

Mine need replaced again -- I've done this twice already, the last time just a year ago. It's not a particularly difficult or expensive to do, but it seems to me it shouldn't be necessary this often.

[joe]

Ralph, have you checked the suface where the races mount? Maybe a race was spun in the housing at one time and distorted the cast surface so the races don't sit square?
I didn't really look at your original post and this reply window doesn't show your profile/rig etc but if you have an AMC20 are you getting the axle nut tight enough? Takes like 285 ft-lb plus?

[porkchop]

If you have a bent axle shaft it can cause the bearings to wear out a lot faster. Did you check this?

[joe]

You might also want to check if the axle/housing is still mounted straight and tight. The rears have been known to move somewhat at the mounts and become cock-eyed and not 90 degrees to the frame. It's pretty hard to spot with a casual glance but a few measurements wouldn't hurt. A friend finally found this prob when he couldn't eliminate a vibe at speed and after doing mega bucks on the front suspension including a front axle swap he found the rear axle to be off square about 1/2" :(

[ibnfe]

I hate to take this one, but are you sure you're packing them completely prior to installation?

[Ralph]

Thanks for the responses, guys. It always helps to get the perspectives of others in a quirky situation like this.

Joe, I've got Dana 44's front and rear on my 1988 Grand Wag. When I get into this in a day or so, I will definitely check on the condition of the bearing seats in the axle tube. I have a buddy who wore his out so bad he's got to get anothe axle tube altogether. Your idea about checking the axle-to-frame angle for squareness is excellent; I changed my rear leaf springs a few months ago, so it's quite possible something wasn't perfect.

PC, I'll check the axle shafts, but they're pretty stout. Again, an excellent suggestion.

ibnfe (What does that stand for, anyway?), I did carefully pack the bearings last time even though I didn't think it was called for. These bearings aren't self-sealed, because the first time I used those and they went to heck in a handbasket pretty quick. But the axle bearings are supposed to get lubed by the gear oil splashing through the tube. At least that's the theory.

So, I'll check for squareness, signs of wear, and straight shafts. Hmm, this sounds like my bio...

[ibnfe]

IBNFE, as in I Be aN FE, FE stands for flight engineer, my job in the infamous military. Any of ya'll follow the Hainan story a lil' while back? That's what I do, but no, I wasn't one of 'em, just friends and "shipmates"! Anybody read "soldier of fortune"? I do the same job as the guy on last months' front page, atleast, I heard he was on the front...!

[ibnfe]

Oh yeah, don't know about yours, but my axles (model 20 rear w/ one piece axles and uses Dana 44 bearings, I think) have an inner seal as well as the outer seal. I don't really know if they get lubed by the gear oil, but I assume the inner seal is to keep the bearing grease and oil separate?? Then again, I may be out in left field on this. Anybody else have this bearing issue by the way? Federal Mogul bearing p/n for AMC 20 wheel bearings is A-5, not so on mine. FM pn A-10 is the bearing that goes in mine, which I'm pretty sure is a Dana 44 bearing, right? But I've never seen a D44 with a round Jeep corporate cover, not to mention that the AMC 20 Auburn posi and gears fit it like a champ!

[jeepbob]

The reason you must pack the bearings is that they will not get lubed from the gear oil soon enough to prevent failure. Also check that the housing is not bent as this will also wear out bearings fast.
BTW the old rigs like mine have grease zerks for the rear axle bearings, so if they are greased once and a while they live a long long time. It also freaks out the guys at the quicky oil change place.

[Brazzy]

I had a L rear bearing bad on my rig when I bought it, went bad again in about 15k miles.
The drum had a chunk of metal missing and I assumed the axle was prolly bent when the chunck was knocked out,so I replaced them both. Havnt heard the telltale whir for about 12k Think I solved mine. :D