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This is my first time performing a rear axle shaft bearing service on my '55 Clipper Custom. While I've followed the service manual's directions to the letter, I'm not really comfortable with how things are coming together and hope to obtain some feedback from those who have gone down this road before.

As background, I have no history on the last time the rear axle was serviced. At the time I pulled things apart I was experiencing an intermittent grinding noise coming from the left rear drum during braking. My initial inspection revealed that the bottom edge of the secondary brake shoe was touching the drum just enough to polish the tiny rivets that are arrayed along the circumference of the underside of the brake drum. I figured one of three things may be wrong: 1) the hold-down hardware was fatigued and allowing too much in-and-out movement of the shoes; 2) the end play of the axle shaft was out of spec; or 3) the drum was warped. With this in mind, I decided to address the issues regarding the brake hardware and axle end-play first.

After disassembling the brakes and removing the outer seal, .010" shim stack, and bearing race, I removed the right axle shaft and pressed the existing roller bearing off the shaft. The new roller bearing (Timken 25877) was greased and then pressed back onto the shaft. I checked to make sure the polished side of the thrust block was visible inside the axle tube and then reinstalled a new inner seal, the axle, and the new bearing race (Timken 25821).

The left side was then addressed in a similar manner with the only difference being the removal of a slightly thicker shim stack measuring .025".

I then began reinstalling the backing plates, but stopped before tightening anything as it was clear that the existing shim stacks were of insufficient thickness for the new bearings. After an afternoon of learning how to make shims myself, I settled on a combination of a .024" stack on the right and a .020" stack on the left with an end play measurement of .0045". I did not have the tool to measure the end play as shown in the manual so I used a dial indicator instead.

Up to this point I felt fairly confident of my progress and proceeded to reassemble the brakes with new hold-down hardware and new return springs. But then I spun the right axle by hand and heard and felt a slight "clicking". I checked the left side and found that I could hear and feel the same slight clicking almost as if the bearing wasn't fully greased. I added the drum and the tire/wheel and the noise never changed.

My only experience with automotive roller bearings is on the front wheels where they spin freely, smoothly and noise free so I expected the rears to be same. Can anyone here confirm what the rears should feel and sound like? As I said earlier, I greased the bearings prior to pressing them on the shafts using a grease gun and bearing adapter, and again by hand right before inserting them into the axle tube. I serviced one side at a time to make sure the thrust block didn't spin, and I'm pretty comfortable with my end-play measurement. So what, if anything, did I do wrong?

As always, any experience and advice you can share is very welcome.

-Scott

You are most likely feeling the differential bevel gears as they are a rather coarse pitch. Thee is no way for an undamaged tapered roller bearing to be notchy.

That's what I was hoping was the case, but this being my first effort with one of these, I didn't want to make any assumptions. Ironically, my son took a bunch of pictures as we took things apart but in the end we needed to hear what things originally sounded like not see what they looked like.

As usual, thanks for your thoughts, Ross.

Scott