Full floating rear axle question (6 Viewers)

[FreddyK13]

Good day all. I am hopeful for some help and hopeful I am in a good forum to ask my question. Most google searches relating to my issue, led me to this site. After watching a few videos, and reading here, it appears the 80 series full floating axle are similar, if not the same.

A year ago, I purchased a 1987 Toyota motorhome, with a full floating 1 ton rear axle. When I had it looked at (before a 2800 mile drive home), it was determined that a rear axle seal was leaking on. They repacked the wheel bearings, replaced both inner and outer wheel seals and cleaned and adjusted rear brakes. all was good for 3000 miles. About a month ago, (and 1500 miles ago), I swapped the rear diff (4.10 to 4.88). I believe I was careful in removing and reinstalling the axle shafts, but a slight leak has developed at the axle flange. I only used the paper gasket (from Toyota). Some on the Toyota Motorhome forum have suggested a little RTV will solve my probelm. Will it? Short of taking the drum assembly off (a little outside my comfort zone), is there any way to tell if the leak is going to affect the brakes? Will I see evidence of the leak, at the back/bottom of the drum? Is the only explanation for gear oil leaking at the flange paper gasket, that the inner seal is leaking?

Hoping some can help. Thanks in advance!

Fred

 

[White Stripe]

You have to take it apart. Cant tell what's going on with one picture. May need new seals and to be properly adjusted.

 

[JoeCova]

May need new seals. Have to take it a part and do it right.

As far as paper gaskets. I recommend using Permatex aircraft form-a-gasket and fully coating the paper on reinstall. It stays relative soft, keeps the paper from becoming brittle and stuck, forms an additional protection for leaks and cleans off with brake cleaner.

 

[FreddyK13]

You have to take it apart. Cant tell what's going on with one picture. May need new seals and to be properly adjusted.

Thanks very much for the reply. I figured as much. Wasn't looking for a diagnosis, based on the one pic. More, looking for an understanding ... is a leaking inner seal, the only way gear oil can get to the paper gasket? Is the paper gasket only there to keep stuff out (water, dust), or does it keep some fluid in, as well?

 

[FreddyK13]

May need new seals. Have to take it a part and do it right.

As far as paper gaskets. I recommend using Permatex aircraft form-a-gasket and fully coating the paper on reinstall. It stays relative soft, keeps the paper from becoming brittle and stuck, forms an additional protection for leaks and cleans off with brake cleaner.

OK, thanks for the reply and the suggested Permatex.

 

[JoeCova]

Thanks very much for the reply. I figured as much. Wasn't looking for a diagnosis, based on the one pic. More, looking for an understanding ... is a leaking inner seal, the only way gear oil can get to the paper gasket? Is the paper gasket only there to keep stuff out (water, dust), or does it keep some fluid in, as well?

I can’t speak to the motor homes but on the full float 80s, the inner seal keeps the diff oil out of the wheel hub. So if you have oil coming out of the flange then it’s getting past the seal and souping up your bearings.

Ive read the front seals will, over time wear a grove in the axle itself, causing leaks but don’t think I’ve read anything on the rears having that issue.

 

[Broski]

If it’s leaking that bad like others have said it needs to come apart.
Never had a single issue with paper flange gaskets in 10 years of ownership.
If everything is working properly gear oil should never reach that gasket.
IMO adding permatex just makes clean up harder next time you’re in there.

 

[jonheld]

Ive read the front seals will, over time wear a grove in the axle itself, causing leaks but don’t think I’ve read anything on the rears having that issue.

Went through this a few months ago on my LX450. Wound up replacing both rear inner axle shafts after trying for months to keep them from leaking. Both sides were heavily grooved where the axle seal rides, not to mention twisted splines on both.
The rear FF is significantly easier to work on than the front.