[lucky1]

Aside from noises are there any warning signs a Chevy 12 bolt axle bearing is going bad ??

Tks.

[mgarblik]

If the bearing is really bad, it could rip the seal and you would have a leak visible on the backing plate an on the brake shoes.

[TedRamAirII]

Get it up off the tires and get your hand on the housing near the backing plate, you should be able to "feel" the roughness. Or grab a coil spring and feel it, then compare sides. While you have one out, check the other side. Usually when you hear them, the axle is trashed also. Using the axle as the inner race was one dumb engineering idea.

[77 TRASHCAN]

The pass side is usually the first to go.
I can’t recommend a way to tell, other than disassembly....

[Greg Reid]

I had one bad about a year ago. It was easy to tell when I pulled drum off and rotated it. First off, it had a rough spot as it rotated and second, I could actually grab the flange and 'rock' the axle up and down. Not much movement but any noticeable movement at all is proof that the bearing is gone.

[steve25]

Lets face it , if you have a 30 year or more old Dif, and all it's ever had are fluid changes, then it's hugh time it got atleast new axle Bearings even if you have no issues now!

[Sirrotica]

The 8.5 axles have the same engineering as the 12 bolt does with the bearing using the surface of the axle as the inner race. When I was working on these in dealerships and garages, we used to just raise the tire off the ground and try to lift it up with a pry bar. If it was in good shape there would be no play up and down. If you could feel play chances were good it would at a minimum need a bearing, upon disassembly if there was a ridge on the axle you were going to need all the components including the axle.

As has been said there was only noise if the parts were really worn, and a tell tale sign was a failed seal with gear lube leaking from the seal area. Very common for the seal to leak before you heard noise from the assembly.

[lucky1]

I see NAPA offers several bearings

Any recommendations as to which are better than others ??

Thanks. As always.

[72projectbird]

Originally Posted by lucky1

I see NAPA offers several bearings

Any recommendations as to which are better than others ??

Thanks. As always.

The problem solver ones often create new problems, so I'd stay away from them.

For axle bearings I usually use Timken.

[Formulajones]

Timken

Avoid the axle savers. If the axle is toast, better off just replacing the axle. If that ends up being the case it's a nice time to upgrade for not much money. Moser offers a stock type C-clip 30 spline 12 bolt axle that is non tapered and 30% stronger than a stock axle and they are relatively cheap as far as axles go. I've been running a set of those for 20 years in a 4100 lbs. car that cuts 1.5 60's and they've been flawless.

[Formulas]

Timken is top dog but I wouldn't hesitate a German or Japanese, France country of origin. just no Mexico, China, Indonesia, Taiwan, Pakistan, and so on

[Skip Fix]

Autozone carries Timkens.