Blog

Recently I endeavored the task of replacing the front and rear brakes along with the master cylinder on my Impala SS. This is when I discovered a pretty substantial rear differential fluid leak:

This was just after wiggling the axle up and down a few seconds.

As you could imagine, the fluid was everywhere on that side:

Sometime in 2012, it started making noise in the passenger rear axle bearing area and through my experience, I already knew what was happening. No surprises here, that axle is toast:

 

Here is also a quick video of the bad bearing in action: Video of Bad Axle Bearing

So, after procrastinating for one reason or another over a 6 year period, I finally bit the bullet and decided to replace the rear axles/bearings/seals.

A while back when I first started pricing this job out, I discovered that Moser Engineering made aftermarket replacement axles at a reasonable price ($260.00 a pair) and were readily available through Summit Racing. So I ordered everything up and away I went!

After jacking up the car and removing the wheels, I disassembled the brakes. Then it was time for the hated crawl underneath the car (I really miss my lift) and removed the rear differential cover and rediscovered the wonderfully (<--not) distinctive smell of gear lube...

As you can see below, at some point I had already upgraded the rear differential cover gasket to the Fel-Pro RDS55028-1 Rear Axle Housing Gasket. 

The Fel-Pro Gasket shown above has the slots on the sides to allow for the fluid to be transferred to the axle tubes and eventually the bearings on the end. The factory gasket had inadvertently blocked these holes which prevented the fluid from properly reaching the bearings eventually causing failure. I immediately changed that gasket out when I bought the car in 1997 when it had only 28,000 miles.

If you look closely at the rear differential cover, you can see there is a magnet. All of those fine silver colored particles are from the clutches of the limited slip differential. I went ahead and cleaned up the cover so it was read for a new gasket and installation:

Next I rotated the ring gear around to gain access and removed the differential 


With nothing else holding them in, I removed the axles.

Now we can finally get to the bearings and seals:

I used this tool with a slide hammer to remove the bearings:

To install the new bearings, I started to use a bearing race installer which was working well until I ran out of depth so I switched to a large impact socket which worked flawlessly. I installed the seals with a proper seal installer. I didn't get any pictures of that but here is the end result:

So I moved on to installing the wheel studs:

stud pics here

I pre-lubed the bearings and seals with the factory additive integrated rear differential fluid:

And then inserted the new axles, one side at a time. Pushing them all the way in, installing the c-clip and then pushing them out as far as they would go to lock them into place: