Axle seal:72 eaton 3/4 ton

[scotts 72]

Have been having trouble with axle seal on my 72 K-20. The drivers rear seal is leaking axle fluid on the brake shoes. Have replaced the seal twice,, even tried puttin it in backwards to see if that made any difference.It did not I noticed the bearing and race are made by two dirfferent manufacturs. Could this be the cause. Aren;t the bearing and race supposed to be a matched set? Isee no burs or scares that would cause a leak,,, should i try to replace the bearing and race that are on the truck now? Thanks for any help.

[4x4Poet]

Originally Posted by scotts 72

...I noticed the bearing and race are made by two dirfferent manufacturs. Could this be the cause.

Most likely.

Aren;t the bearing and race supposed to be a matched set?

Yes. And a new bearing needs a matching new race, which probably hints to what happened. A PO installed a new (or maybe even used) bearing in an old race or installed a new (or maybe even used) race in with the old bearing.

Isee no burs or scares that would cause a leak,,, should i try to replace the bearing and race that are on the truck now? Thanks for any help.

Yes, the mis-matched (probably from unequal wear and tear) bearing and race could allow slop in the bearing's movement between the spindle and the race. This induces excessive hub movement that flexes or wallows out the rubber of the seal beyond called for tolerances, thus creating a leak. And if they are roller bearings, you could have a bearing sales store cross ref them to better tapered bearings (and races).

Edit: Verify that you have the correct seal. Make sure the slip fit around the place its rubber rides on the spindle would provide a seal under rotation. And just to be thorough, be sure that the seal is installed square/flush in its bore.

[jlhusa1]

Did you look at the surface on the differential housing that the seal rides on? It has to be perfectly smooth. I have seen them have grooves worn into them. It can be easily repaired with a speedy sleeve.

[4x4Poet]

Originally Posted by jlhusa1

Did you look at the surface on the differential housing that the seal rides on? It has to be perfectly smooth. I have seen them have grooves worn into them. It can be easily repaired with a speedy sleeve.

Scotts 72 has a 3/4 ton axle. Full-floating, so it has a spindle bolted to the housing for inner and outer bearings to ride on.

Scotts 72, If you can't feel any grooves with your fingernail or see damage (burrs, deep wear marks etc), I'd say that the spindle is not likely worn at the seal mating surface since it is hardened tough.

[scotts 72]

Thanks to all. Will try a new set (matched) bearing and race. I see no grooves up where the seal sits,, afriend also sugjested A sleeve simular to the type you use on a harmonic -balancer.,,, is this what you refer to as a speedy sleeve?

[scotts 72]

Ordered new bearing set,still has not arrived.Hope this fixes the problem. Can you still buy the spindle if it turns out that I need one?

[Americanrider]

If your close to me I'll sell you a whole axle from a 72 K20, 4.10 gears for $100 and even help load it! I'm going to a 14bFF

[4x4Poet]

Buying a new spindle would be a waste of money since wrecking yards have plenty of spindles in fine shape for less cost and that should last just as long as most on trucks today.

[Blazer1970]

Unless I am missing something, the spindles on a full floating rear axle are welded to the tubes. You can't just swap out a spindle.