Differential - driveshaft seal

[leftfield6]

My 1991 Ram 50 has a leak at the front nose of the differential, where the driveshaft connects. I haven't dug into it yet but I assume there is an oil seal there that has given up on performing its duties.

Is there a how-to posted somewhere on this job? How big a pain in the tuckus is this going to be be?

i feel like i need to do this soon, it's actually leaking enough that it is slinging lube on the underside of the bed and all nearby suspension components.

[camoit]

Remove drive line. remove large nut with impact. Swap out seal. reinstall in reverse order. Just be careful not to over tighten the big nut as it will change the way the pinion to ring gear is set. In other words. snug not tight. Oh and go get a new nut. Also look at the drive yoke. It might be bad and have a grove where the seal was riding.

[leftfield6]

Well, dang it, that didn't work out. My impact gun, or my compressor, one or the other, didn't have the guts it takes. The big nut would not budge. Tried heat, penetrating oil, everything. No budge.

Bolted things back up and I'll take it to a shop that has a lift and a bigger impact wrench.

[leftfield6]

This is really odd, but it seems to have self-healed". When I was attempting to replace the seal a few days ago, I had already drained the old lube before failing in my attempt to remove the seal. What drained out was very thin and didn't even smell like gear lube. I replaced it with fresh gear oil.

So now. I've driven it about another 150 miles or so, and now it's not leaking a drop. Go figure.

[pennyman1]

it might have been water, or worn out gear lube, although it ususally smells like an old burning sulpher mine and comes out like tar.

[camoit]

Many times you need to build a tool to hold the yoke so the force of the impact will go into the nut and not into the rear end. Other wise there is to much slop to get the nut loose and back tight.
What many shop do is take a peace of 1X1 square box tubing, long enough to go from the yoke to the ground. About 2 foot long. Then on one end drill a hole through it. Then about 8 inches away drill another one. Then we take some long bolts and run them through the two holes. Then cut another peace of tubing just long enough to extend over the bolts. Drill holes in that peace.
You have now built a clamp that can grip the sides of the yoke and hold it tight, while the impact hits the nut the force is transfered through the yoke into the tool and into the ground. Then the nut will turn. But of course it has about 175 FtLb of torque on it.