Leaking hub seal = bent diff housing?

[mnemonix]

The plan for today was to get the front diff in my sierra rebuilt.
Sent it off to a local business with all parts and high hopes/expectations.
However things took a turn for the worse when I recieved the dreaded phone call.

After replacing the swivel kit/hub seals, the mechanic was unable to get the seal to seal. When filling the diff up with oil, it would piss out of the passenger side seal. Tried 2 genuine seals but without luck.
Axle runout tested ok.
He seems to think the likely cause is a bent diff housing preventing the seal from seating properly around the axle.

Are there any other likely causes or possible solutions to consider?
It would be a bonus if I don't have to swap the diff out just yet to avoid the work of making up new spoa perches etc.

Thoughts?

[ajsr]

did it leak before your had the kit put in?

[mnemonix]

car is new to me.
diff oil had the consistancy of toothpaste, so leaking from this seal was not really major, however it was present.
The previous seal was siliconed in place by the backyard genius who installed it, so the problem obviously existed prior to today.

[ajsr]

maybe not I always put sealant on mine.I find if easier to fit then as they slide in easier and you know its sealed around the outside.
how good a mechanic is he ???
I know it sounds bad but they wouldnt be hard to damage if installed wrong.Id think your diff would have to pretty bent for oil to piss out,maybe weap out but id think that was it.

[mnemonix]

It's not a general mechanic, it's a specialist diff workshop with a decent reputation afaik.

Their solution to get the car back to me was to remove the front driveshaft, unlock the hubs and drain the diff oil so it couldn't leak.

So I'm $500 lighter, with a 2x4 sierra.


Another interesting thing I noted, on the drive home I had a constant irritating squeal from the same hub that is leaking.
Any time the car is moving it squeals - loud enough for other traffic to stare, Other drivers could hear it even with their windows up.
By the time I got home (20 minute drive) All I could smell was burnt rubber.

I'm less than impressed at the moment.

[ajsr]

something wrong there dude
but im at a loss now.
I know my mechanic mates get their apprentices to do these type of jobs normally so you may expect it then but????
sorry mate cant help

[MUD-PIGSIERRA]

Passenger side is the longer axle of the two, being that the work has been done by a "trusted" mechanic makes things hard to work out. Things that pop into my mind could be the correct adjustment of the King pin bearings with the metal spacers, but still unlikely. Did the mechanic take the whole hub assembly off before putting the axle back in, you need a bit of angle some times putting them back in and doing it with the hub out of the way means less movement on the axle seal.

I thought I was dropping my Transfer case of too a trusted Gearbox, trans and transfer case specialist as well, the guy is well known for quality drag racing boxes as well. When I got my Transfer case back it leaked in two places and had play in the rear shaft which caused enough movement that my drum brake shoes and springs were wrecked. I had to take it all out and take it back to them, when I get it back that afternoon he tells me his other mechanic did the work and forgot a washer in one spot, and they found it on the bench.

[ScrawnC]

I would hazard a guess that it's a bent housing too, but that wouldn't account for the squealing noise. You can get the housing straightened if you don't want to re-do spring perches. It only takes a little bend in the housing on that long side to make that seal leak.
You may need to drop back in and get them to recheck the squeal, if it's making horrible noises and smelling like burnt rubber then there is something wrong.

[Jacked]

when things bend and you pull them apart and put back together without repairing the bend you run into trouble!!!
when disassembling the bend probably moved to its relaxed state as having an axle running through and hub bolted on would of kept it straiter then it wanted to bend.
when they where re-assembleing they would of had to "force" it back together. (prick of a job)
no matter what you do you wont get it right until you repair your housing.
squealing noise would be combination of axle rubbing on seal (also burn rubber smell) and hub assembly not lining up within tolerance.

[Ridge]

that squealing sound may also be shot wheel bearings. were they replaced when the diff was sent to the shop? that burning smell could be due to a seal not being installed properly, seated unevenly.

i did my whole front end 2 weeks ago, with no problems. did not need to use silicon to hold the inner axle seal in place.

[mnemonix]

Decided to save the stuff around and just grab a new housing.
Picking one up this arvo and tinkering with it over the xmas break.