I had a mechanic look at my poor braking. I checked everything myself, but couldn't find a problem so I caved. The mechanic said the left rear axle seal has a slight leak and the gear oil has gotten all over the brake pads. He says I need to replace the pads and the drums. Is this normal, can't they just be cleaned with brake cleaner? Are they permanently contaminated with gear oil?

Secondly, is it common for the seals to go out. I replaced that same seal 2 years ago when it and the bearing went out. I used factory parts to replace. It was far more obvious before, I could see gear oil every where. This time a simple visual doesn't show me anything.

Maybe I just screwed the job up.

Yes, you do need to replace the pads, but not the drums unless they have been turned too many times or have grooves worn in them. Otherwise, just have them turned and reuse.

Leaking rear axle seals are pretty common. Marlin Crawler makes an HD rear axle seal. Check out his site at www.marlincrawler.com I'd HIGHLY reccomend this seal.

Yep, easy to screw up the seal. I just did mine recently, and screwed it up. Its leaking now. So I'm going to redo it with a marlin seal. When insalling the axle back into the housing, you want to be very carefull not to let the axle rest inside the axle housing before its inserted into the differential. If you let it rest on the housing, it sits on the face of the seal and deforms the seal instantly. Also I've hear people reccomend putting grease on the lip of the seal before installation.

You might also want to check your rear diff breather to make sure it is not clogged up. If it is, it can let pressure build up inside the axle as it heats up and that can force oil out past the path of least resistance. I had a case once when a partially clogged breather line I added was letting pressure build and that forced oil out past the pinion seal. I rerouted the vent line so that it had no dips in it where gear oil mist could condense and pool and that cured the oil leak, once the seal was replaced (for the 2nd time).

another thing to check out is the axle shaft its self, sometimes grooves get worn in them, causing the seal to properly sit. also if the axle is pitted it will cause damage to the seal.

Could be bent too.

Besure to lube the seal before inserting the axle. A dry seal is easier to nick, cut and/or tear. If there is a groove in the axle where the seal rides on it, just press your seal in a liitle more or less so the seal rides on a smooth part of the axle. This trick works for the pinion and front motor seals too.

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