When I bought my new 92 I knew there was a bearing issue, but originally when I found the pass rear bearing shot, i thought I was done... To my surprise, I wasn't done... and found something interesting in the front axle.

Seems as though the bearings were changed or altered once before, so it appears.

The inner drivers wheel brg was beat to death, and so I went to buy new bearings. The guys at the parts store matched the Timken part numbers on the original bearing and race (as I requested them to) and I passed on the listings in the computer.... (bad move on my part) as I assumed the original bearings were correct.

Well, as I began the reassembly, for some odd reason, I decided to "test fit" the dry bearings prior to assembly. Really glad I did, as I discovered that the inner bearings were not matched and most likely the cause of the failure, as they appeared to be greased properly when originally removed.

The original bearings that were in the truck were mismatched on the inner, as you can see in these pix. The brg sat too deep in the cone.





The new bearing and cone (from the actual listing i their computer) fit together correctly.





Point of the story is to not assume that the parts on your truck are correct

 

I don't know if it is the situation in your particular case, but:


Regardless of brand, probably 99% of 8-lug on 6-1/2 hubs have at least one JLM104949 bearing; many will have both bearings that size.


Probably 90% of these JLM104949 bearings will be running in a JLM104910 race.

There is, however, the occasional hub that uses the same JLM104949 bearing, but in a JLM104911 race.

It is an easy mistake for a parts-man to be in such a habit of automatically reaching for a JLM104910 race, that he could give someone the wrong one when they need a JLM104911 instead (or vice-versa) .

 

Oh, and your hand is healing nicely after the sausage-grinder accident.

 

Very perceptive..


4 1/2" 90 deg. grinder with a cut off abrasive blade in it. I was cutting a groove in the old race to use it as a insertion / press tool for the new race.


Ground a groove in my thumb, and just missed going through the underlying fat .... really gross.


T.

 

I didn't know this

The outer brg was made up of the JLM104949 plus the race in what they call a set38, I believe. Can't find my paperwork.

The new inner bearing that was correct was a 387a, and the races I had already purchased were a 382. Those numbers turned out to be correct for the inner races.


Strange part for me was finding the 28682 inner bearing which didn't match the race. I guess someone installed it wrong somewhere in the 150,000 mile past.

T.