Rear diff issues

[Chrispbrown36]

After fixing an ignition issue on Friday I decided Saturday night would be a great night to do some jug fishing. Hooked up the boat and made the hour drive to a new spot. As I got off the interstate turning on to the highway I hear a clunk. Pulled over and looked things over. Nothing really stood out....the u-joints feel tight....but forward and reverse at low speeds I get a clunk with every wheel turn. After I got it home I took off the rear diff cover to look things over. The lube seemed to have been a little low, but nothing excessive. There was a little bit of metal shavings on the magnet, but no big junks. I jacked up both sides and moved things around. The only thing that seemed odd was the driver side seemed to have more play in it than the passenger side. Wiggling it back and forth and pulling it in and out. Any ideas?
And for those that care....the fishing wasn't great. One little channel cat just before I left.....but man was it gorgeous out there last night.....almost nice enough to make me forget about my truck issues!

[Chrispbrown36]

Oh, and I was wondering if having it towed on Friday might have caused an issue. It was hooked up from the rear.

[nonstop]

Cover still off? Pictures?

[Chrispbrown36]

Already put it back on. I want to move it before I start doing anything. Out of convenience last night I pulled the truck and boat into the yard last night and it is on a bit of a hill.....not great for having it partially jacked up. It will be the end of the week before I can get back at it and I will try to get some pictures then.

[Dead Parrot]

If the tow truck hooked up to the rear axle, check all of the shackles and shocks.

Other possibilities: Wheel bearing going out(might explain driver side play), large road installed nail or debris in tire, broken wheel studs, developing tire defect, something in the brake drum.

[hatzie]

Loose wheel lugs will do that too.

[Chrispbrown36]

Everything is on hold til this weekend. I work midnights and after sweating it out all night long I just can't talk myself into working in the heat on the truck. I will post up after I have looked things over again. Thank you for all of the suggestions.

[Chrispbrown36]

I had a set back last week, but on the plus side I have a lot more free time to work on the truck now.
finally tore into the axle again. Pulled the diff cover again and pulled out an axle shaft. The seal and bearing look good. The bearing has some scoring but nothing that you can feel. No noticeable wear on the seal or any apparent leaks. The shaft has some scoring, but you can barely feel it. I can't see anything on the gears that might be causing an issue....no wear or shavings.
I am debating on changing the bearings now. As I said, they look good but I do have it apart. On the other hand money is kind of tight now so waiting on it sounds good. I am still not seeing any play in the u-joints, but I am tempted to change them anyway. What do you guys think?

[1970pelle]

Its very possible its your rear diff telling you its time for a fluid change. And being its a limited slip diff, I would be running synthetic gear lube with a friction modifier. That most likely is what it needs.

KA

[Chrispbrown36]

I was considering going full synthetic, but Auburn doesn't recommend it with their limited slips. I think at this point I am going to clean things up a bit, put some fresh gear lube with additive, and see what happens. I had changed it about a year ago and don't drive the truck all that much, but I did notice that the cover had been leaking some so I might have lost enough over the past year to cause the issue.
While I was under there I decided to look into an oil leak. I had suspected rear main seal, but the same night I had the clunk sound I noticed smoke coming from the oil on the exhaust pipe. This hadn't happened before so I was concerned that things had gotten worse. After removing the bellhousing it seems pretty clear that it is the rear main and it isn't too bad of a leak. I think that over time the leak was filling the bellhousing up and as I drove it was being thrown....everywhere. I did notice that the oil sensor by the oil filter could use some tightening up....seems to be leaking a bit there too. That thing is so awkward to get tightened up....couldn't they have found a better spot for that?

[Chrispbrown36]

Well, I finally got a chance to take the boat out again and I am glad to say that it appears the fresh gear lube seems to have taken care of the problem. Not a single clunk this time.
This is the first vehicle I have ever owned that I get looks of jealousy from others when I drive past....never fails that someone yells, "Hey, nice truck buddy!" or "Man! Is that truck for sale?" I just smile and say, "Trust me....you can't afford what I would want for it."