Minor rear axle leak

[DaveAhrendt]

I've got a very slow leak at the right rear brake backing plate. Over several days a single drop of gear oil will hang from the plate. When I pulled the drum off it was bone dry inside so I assume the seals are fine and the leak is outside the brake assembly. Is it possible for a leak to form where the backing plate is mounted to the axle tube? Any other ideas?

Thanks.

[Steve Simmons]

Most likely it's migrating there. The only place for oil to exit the axle housing is into the bearing carrier. If the oil seal on the rear of the carrier is bad, oil could get through there to the back plate. It seems most likely it would then go straight down but I suppose it could go around the plate if the conditions were right.

Also check to make sure it isn't leaking from the rivets in the axle housing behind the plate.

Here's the are in question with the carrier removed.

[Duncan M]

Another thing to check is that the vent or small hole through the differential filler (top) plug is clear, and venting properly.