leaking Full float hub

raventai · November 7, 2003

I changed the rear diff fluid about 3 weeks ago and I noticed a seep of oil looking stuff on the inner side of the brake backing plate, I cleaned the plate off wile I was cleaning up all the other mess I had made and then forgot about it until I was under th truck again today now it is a full blown leak

this stuff is too viscus to be brake fluid and master cylinder is at it sharpie marked level, I was full of oil so I could not smell anything but I am pretty sure it is 90wt from its location

Ill give it a sniff tomorrow

I have never messed with a FF hub it is hard to replace the seals? Is there several or just 1 like on a semi floater? Anybody run into this before?

2001BLACKHD · November 7, 2003

I had this same problem I beleive on my "01" HD. The rear axle seal was faulty and it let gear lube leak out onto the emergency brake shoes. I noticed that the e-brake was not holding so I brought the truck to the dealer (it had 25,000 miles at hte time) to have it checked. They found that the axle seal was bad. Also found that the new seal that they put in is a new revised version because of this problem. They replaced both sides and I have not had a problem since!

Engineer · November 8, 2003

raventai-

Hub seal replacement on a full floater is simple. Simply remove the wheel, then the brake caliper. Next take the 8 bolts loose that hold the axle in. If the axle doesn't come easily, just pop it with a hammer dead center of the axle flange. Make sure you dont smack the studs. ( this is assuming that the axle has studs and nuts instead of bolts holding it in)

With the axle out you should see the bearing nuts. Probably an outer "jam" nut with a lock tab that will need to be forced out of the way, then a lock ring, and then the bearing nut. You will have to release the park brake, then the hub should slide off.

Other than the fact that you have the axle running through the spindle, the approach is the same as the front wheel on a RWD passenger car, or two wheel drive pick-up.

raventai · November 8, 2003

Thank you both for the info

I'll try to pick up some seals at the dealer Monday, if there is an updated part then I might as well do both sides wile the axle is on stands (right side is the one leaking), if they have them in stock I'll do the swap that day if not I will have to order them from GMpartsdirect.com