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View Full Version : Further discussion of DM rear end, bearings, etc.



DickWells
11-04-2015, 21:02
Trying not to belabor the RW bearings topic, so, changing threads to add a couple more thoughts.

A little over a year ago, I found my passenger-side 11.5 rear-end housing cracked all to heck and leaking like crazy. Wrote about it, here, but never followed up properly, mostly due to not being able to post the photos that I took of the thing. Some day, I'll find someone who can sit down with me and get that job done! Anyway, I put in another (used) rear end and have put enough miles on to tow to Texas and back, plus quite a bit more.

I do think that I know what went wrong with my original rear end. I have an air suspension in there that uses the original front pivot for the steel springs as a pivot point for the new track arms. It uses a Panhard rod behind the axle to control lateral movement. My original ball-end on the Panhard rod wore out and I believe that contributed at least a little to the cracked housing/tube. But, the more significant thing (I believe) is, that the four U-bolts clamping the tubes to the track arms got loose. Not much, but loose, nevertheless. The specs call for a torque of 170 lb/ft, re-tourqued at 10,000 mile intervals. Took care of it for a year, or two, and then forgot about it:o
Now, I've done my initial tourquing and re-tourqued the new-to-me rear-end several times, by the book. When I had 10,000 miles on, after that, I re-tourqued them and did, indeed, get close to a quarter turn out of all 8 nuts, on average. I'm thinking that is what happened to the original rear-end. Especially, since the right side was loose, and, as far as I can recall, the left side was not. So, one side holding solid, perhaps, and the other allowing tourquing of the axle on that side, just might have been the culprit.

And, there's the matter of those track rods not allowing the axle to rotate at all, under power, during the early years.. That's the factor that I have no experience or knowledge of. What do you guys think? Is it possible that the rear-end can be so rigidly held that it could cause that problem, and the tube actually cracked and that allowed the whole she-bang on that side to start shucking and the bolts loosened up?

Long-winded, as usual, but the bearings discussion got me to wondering.

Thanks, DW

Kennedy
11-05-2015, 15:25
I don't have much to add other than that it seems that just about every one of these truck leaks gear oil at the right rear. Just enough to goop the park brake shoes into a big mess.

DickWells
11-05-2015, 18:21
There's that, too. I put two new seals in the right side, rear, on the original rear-end over the years, before it broke.