I posted a while back about losing my rear axle bearing and the
resulting fire at the brake drum area.
Anyhow, I pulled both axles ( I think I have a dana 40? semi-floating rear end, anyhow), and took them to a machine shop to have
the new seals, bearings, and "do-hickey" pressed on. I re-installed,
and had a small leak on the axle that didn't have the original
problem I've pulled it out twice more, added even more RTV around the brake anchor plate to rear end joint, as well as between
the bearing carrier and brake anchor plate. I let it sit over night
without driving it, and noticed a smaller than original leak, but
still a leak .
Am I missing something here? I checked the seal with the axle out, thinking I'd damaged it, but it looked great!

Thanks!
DutchmanAZ
'76 F150 4x4/4spd manual/tired 360.

 

You should have a vent tube on the axle somewhere. Make sure it is open or the axle will build up pressure when it warms up and push oil out around the seals.

 

Thanks! I'll give it a look. I drove it into work this morning, and
now it's really leaking
I'll post back after I've had a chance to look.

 

Could possibly have a groove worn in axle shaft.

 

I checked the rear end when I had it apart again :-X23 last night, and
I couldn't find a breath tube or wear on the axle. It acts as if it's leaking between the rear end housing and the brake assembly plate. I cleaned everything up again really good, put some RTV on the housing, let it sit for 30 minutes this time, and bolted her up.
Drove her to work this morning, and the &^)(*@#&%*(& is STILL LEAKING

Any other ideas for me? I'm getting to the point where I may have to take it to a shop and let someone else try it..Hate to do that.

 

You have a breather tube. It's on there somewhere. My 80 had it incorporated in the brake line tee block.

 

Here's my experience, hope it helps. I had a leaky bearing seal and was leaking on the inside of rear wheel, soaked my brakes. I had a shop-who employed young mechanics-replace the axle bearing. Three months later it leaked again. I had it replaced again under warr.

Since my truck is more of a toy I didn't drive it much and months later it was leaking again. I had the tech. college automotive shop students (labor at about $10/hour) look at it while they were doing alot of other work on it. They reported "I have an out-of-round axle housing" but they would put it back together with some RTV sealant and hope it seals. They also installed all new brakes/drums/brake cylinders on the rear. I then moved across the country and it started leaking again.

Figuring I needed to have the axle housing replaced or cut and welded I asked around to find an experienced shop. It turned out to be a specialty racing rearend setup shop who knew exactly the problem, had seen it before and had cut off housing ends and could weld on replacements (they are available). Luckily the mechanic had years of experience. He got into it and found "your backing plate on the two piece bearing is not the right plate" This is the plate which fits into the housing, inside the wheel and helps seal everything. He said showed me how it didn't fit correctly. "I think I might have one in my box o' parts". . . Sure enough he did, repaced the bearing, seal and buttoned it up. They took me for about $400 but this solved the problem.

My '79 F150 4x4 has a replaced rear, an '85 Bronco 9" limited slip from previous owner. Somehow the backing plate was substituted and started all my problems. After a new 400, new custom dual exh., all new Edelbrock intake, Cer. and fresh top quality paint it was so nice to finally cure this last problem. Good luck.