I was doing a ring/pinion swap tonight, and when wiping out the housing I saw lots of fine glitter on the rag. All the bearings are pretty recently replaced (within past 10k miles), and all look fine (no obvious pitting). The only thing that doesn't look fine, and the only place that I can figure that maybe the glitter is coming from, are the axles. They are pitted where the wheel bearings ride. I saw some pitting when I put the new wheel bearings in 10k miles back, but I didn't want to spend the $ for two new axles. The carrier is a new addition that I put in from an ebay buy about 5k miles ago (limited slip carrier). Do the limited slip clutches shed some particles? I can't imagine that it would be this pronounced. So, the million dollar (or maybe $250) question is, does it sound likely that the problem is with the axles? My '83 F150 is a beater that I use to haul wood and general work around the property. I'm not looking to have racecar performance, but I certainly don't want my entire differential assembly to get screwed up from having the metal flakes circulating in the housing. Anyone with experience in this kind of issue? Ford 8.8" rear end, 31 spline. Thanks.

 

I've just been searching & reading about this for my Dana 60 rear wheel bearings (which, as it works out, are still fine); the set-up is the same as yours with the rollers running directly on the axle shaft.

When the bearings wear, they slowly damage the axle surface leaving it unfit for new bearings to run on. Replacement repair bearings are available which are offset to run on a new, undamaged section of axle. The original bearings have bigger rollers - maybe the repair bearings won't last as long - I don't know.

RockAuto have them listed. The bearings for the D60 axle are $48 each, and include in-built seals & o-rings.

 

You can try the repair bearings, but they are a band aid. I am sorry to say, but the right way to fix them is by putting in new or JY axles with no pitting.

 

I purchased the offset bearings, and took a close look at them prior to installing. Unfortunately, they ride about half on the non-pitted surface, and half on the pitted surface. I don't think that's a good solution. I think I'll return them, and see what I might be able to find at the yard in terms of used axles. New they are around $130 each even from autozone.

I looked at the old bearings, and they appear to be ok. They only had about 5k-10k miles on them. The axle seems to be the thing that is breaking down. I think I'll clean them and then re-pack. Thoughts?

Final question - why is it that we pack wheel bearings, but we leave carrier bearings unpacked and permit the gear lube to do that lubrication job?

 

The grease is just for initial lubrication (on this type of axle) until the oil has travelled out to the bearing. Some rear wheel bearings are solely grease lubricated , & sealed off from oil contact.

Something's not right regarding the repair bearings; they are designed to be outside of the old wear area completely....maybe you've been supplied incorrect replacements.

If you do get other axles, for the cost involved, I would personally use new bearings - the roller surfaces will have been affected by the axles breaking down, even if it's not visible yet.

 

OK, that's probably good advice wrt the new bearings. Concerning the replacements, it fooled me also, and it does seem weird. The picture in the leaflet enclosed with the bearing clearly shows that it should be the way you say, but I made measurements and it just doesn't work out that way. Interestingly, the rollers in the replacement are the same size (width) as the original bearing rollers. I was expecting them to be smaller.

In fairness, I purchased these (Moog/National) at Advance. The Timken TRP1559TV sold by Rock Auto (that you mention above) may be a different style. These National bearings seem to be multi-purpose, and intended to help when either the axle is worn, or when the housing is worn. The bearings and seals (they package a seal on each side of the bearing, which is packed in grease) are packaged in a pretty robust mechanical housing.

I'm going to go to the yard on Sat and see if I can get a pair of axles for cheap. If so, I'll take that route. Thanks for the advice.

 

I've been looking at some diagrams, and I think that I can illustrate what I'm seeing on my axle. For example, see page 2 of the diagram at http://autoam.timken.com/techseries/...airBearing.pdf
If you look at the picture, the actual rollers of these replacement units seem to straddle the transition in outer diameter of the unit, i.e. where the OD changes from the larger OD (where the seal would normally sit in the housing) to the slightly smaller OD (where the bearing would normally sit). In the diagram, they show their "original roller path" further in, removed from this transition. But truth is that on my axle at least, the original rollers consumed 95% of the width of the original bearing housing, which essentially fills the slightly reduced OD region machined for the bearing housing to sit (between seal and axle housing). So the pitted path is right up against the transition I describe above, and therefore the replacement bearings that straddle this transition will run partially on the pitted region. I have looked at this numerous times, and I just don't see any other conclusion. Am I missing something?

 

Your best route is other axles, either JY or new, and Rockauto has them for $96. How is the rest of the rear end? You might be coming out ahead if you get a whole rear end from the JY, that already has the gears you were going to swap to. You could try to find a 9 inch (better rear in my opinion) that will bolt in and they do not use the C-clip design. Just a thought. You could then sell the parts that you were still good off of this rear and make some money to pay for the other rear.

 

I thought I was successful on Saturday at the yard. I removed two axles from a F150 that looked like a similar rear end. I took along the measurements of the lengths of the axles, and the diameters where the bearings ride, and of course the fact that it's a 31-spline. But when I got home I realized that I missed one crucial measurement - the extension sticking out of the center region on the flange where the lugs are inserted. My original axles were about 2-7/8" diameter, and these new axles are about 3-3/8" diameter. The drum (for the brakes) has to fit over this, so I obviously have a problem. I can return the axles and look for another set (but with the new info in-hand), or alternatively perhaps there are drums with the larger id?

Dumb mistake, but those are the kind I usually make. Anyone with any pointers or insights?

 

Went back to the yard and found a couple of the right ones. But interesting thing, I took the time to examine two brake drums, one from the 2-7/8" center region axles and one from the 3-3/8" axles. The drums looked identical otherwise. The specific 3-3/8" axles that I used were from a 93 F150. It wouldn't surprise me if the 93 drums would fit my 83 truck. I know that the axles did. But I was tired of exploring, and I decided to keep things stock...

 

I think Ford changed the length of the axles on the 8.8 in '87. I swapped in a newer axle in the drivers side of my '85 and had to shorten the splined end of the axle by ~.20" to make it work; I couldn't get the C-clip in until I cut the axle . It wasn't pretty but it had to be done and is still in that diff w/locker ~50K miles later... Look closely at the distance between the C-clip groove and the end of the axle (splined), compare both axles side by side.

 

Hmmm, well, perhaps I overlooked something. I know that I had inserted the (incorrect) axles into the truck w/ c-clips installed and had the differential sealed up and oil back in before I realized (when I was ready to put the drum and tires back on) that I had a mismatch problem at the axle end. Anyway, I found the right ones, so I'll use those now. I felt like a proctologist yesterday at the salvage yard - I had my fingers in more rear ends than I care to mention. These axles are a major wear item, apparently, because quite a few of the units I opened up were pitted. Of course, you need to crawl under the car, take off the cover, remove the pin and c-clips, and then beat the heck out of the rusted-on brake drums before you are ever able to judge the value of the axle. I almost gave up, but then found a good one. There were numerous axles of the larger size I mention above sitting around, for some reason, and I took note that none of them were pitted. I know that the larger axles that I removed on Saturday were not pitted. The race area of the shaft looks absolutely identical to the smaller axles, but maybe there was a materials change or something. Or maybe it's just that the smaller ones are on older vehicles that have been around longer and average more miles. Not sure. Just an observation.

 

In my case it all started on a Sunday morning when we were going to install my new Lock-Right. Well, after a trip to a few JY's it turned into midnight and I was still at a friend’s house looking at a drive home and work the next morning in my future and things weren't going together, not good. I couldn't get the axle in far enough and looked at the spider gear pin and realized that the axle was hitting the pin before exposing the C-clip groove? I suppose this could be a Lock-Right issue but I recall a side by side and observing the difference in length. I ended up cutting the axle with an abrasive disk on the grinder and cleaning it up with a fine file. It did look OK and fit well when done, you gotta do what you gotta do.