rear axle seal leaking

[2deuce]

My truck sat a very long time for reasons I won't get into now, but new seals were installed along with brakes and tires, grease and gear oil were changed.
I dismantled the leaking hub and can find nothing wrong. The seal that was apparently leaking looks good. There was a cork wedge in the keyway. I'm inclined to reassemble everything as is. The outer seal looks like it seals on the bearing race. This is not like an axle seal where it seals on a turning axle, everything is stationary. I'm thinking more pressure on the seal so that it is pushed snugly against the bearing race would be helpful, because I think I had oil up against that seal for a long time. Some may have seeped past the cork too. I looked in the parts manual and I'm not missing anything. It seems like a washer that could flex would be helpful in putting some pressure on the seal, because the sealing area is small on the race. What do you guys think?

Thanks

 

[topo]

Maybe a stuck axle vent ?

 

[gringeltaube]

Can you post a picture of that outer seal you are using?

Not all of those seals were created equal... You may read a bit more about it, here...


G.

 

[2deuce]

it is a military seal, I believe. The reason I think this is the case is because the brakes are new, some of the tires are new with the nubs, and the rest are like new. It also would make sense that new seals would be installed.

 

[2deuce]

I don't have much experience with trucks larger than a pickup, so telling when you have correctly adjusted your bearings is difficult for me and I'll have to drive the truck to see if excessive heat is generated.
I believe I have an idea why my axle was leaking. I remember when I removed the inner nut it was finger tight. I don't think that is tight enough to put sufficient pressure on the seal and it didn't seal. When I was adjusting the bearing, backing off the nut anything over 1/4 turn made the nut and seal loose. Some here have recommended 1/2 turn backoff. On my truck anything over 1/4 turn leaves the seal and nut loose, which will cause the leakage I had. Possibly all trucks are slightly different on where that nut should be. I don't think it will leak where I have it now. I just need to make certain it is not too tight. I'll have to check it after driving.

Thanks

 

[bigmike]

You need to tighten the bearing down until it drags, then back off 1/4 turn.

 

[topo]

Try this tighten the inside nut back it off retighten torque to 75 foot pounds if you have a torque wrench .
Back it off 1/2 turn rock the brake drum at the top in and out you will feel lots slop .
That is the movement you are trying to take out when your nuts are adjusted .
The outer
nut takes some of this movement out by tightening against the inside nut .
the out side nut only needs to be torqued to 150 foot pounds
You are looking for the spot where the slop is barely gone
Start over
Torque inside nut to 75 foot pounds
back off the nut off 3 axle studs ( do you feel slop ?)
Put in your lock and out side nut
Torque to 150 foot pounds ( check the slop )
When done bend over the locking tabs The torque ratings are out of the manual for the m211 GMC 2 1/2 ton truck

 

[rustystud]

I don't have much experience with trucks larger than a pickup, so telling when you have correctly adjusted your bearings is difficult for me and I'll have to drive the truck to see if excessive heat is generated.
I believe I have an idea why my axle was leaking. I remember when I removed the inner nut it was finger tight. I don't think that is tight enough to put sufficient pressure on the seal and it didn't seal. When I was adjusting the bearing, backing off the nut anything over 1/4 turn made the nut and seal loose. Some here have recommended 1/2 turn backoff. On my truck anything over 1/4 turn leaves the seal and nut loose, which will cause the leakage I had. Possibly all trucks are slightly different on where that nut should be. I don't think it will leak where I have it now. I just need to make certain it is not too tight. I'll have to check it after driving.

Thanks

Your bearings where probably adjusted correctly. Remember your dealing with a truck now and lots of heat. The metal of the bearings will expand during use and if adjusted too tight will cause undue wear and eventual bearing failure. On our busses after removing the jam-nut you can usually remove the bearing nut by hand. This is on a 80,000 Ibs rated vehicle (60 ft articulated bus) .
After working in the heavy equipment world for 39 years now I always tighten the bearings the same way. I fully seat the bearings by torqueing down with a large breaker bar to about 250 to 300 ft Ibs. Rotating the wheel assembly the whole time. Then I back off the adjuster nut until it is totally free then retighten until it is just snug against the bearing (about 10ft Ibs.) This method has worked for decades. When you check the clearance of the wheel you should have between 0.00 to 0.002" movement. Some manufactures go as high as 0.005" clearance due to heat expansion. With all tapered wheel bearings the goal is to have ZERO clearance at operating temperature. This is why when done properly the bearing nut should come off with just your hand turning it.