leaky axle seal in 9" axle

[TooeleBronco]

The Ford 9" in the back of my Bronco always leaks. I'll change the axle seal and after a few months it starts to leak again. It doesn't leak bad but after it sits for a day or two you can see gear oil running down the inside of the tire. The axle shafts are smooth and the bearings are good. Anyone have any ideas?

 

[sbr]

Might be a bent shaft thats about all I could think that would do it.

 

[Tacoma]

Seal surface might be worn, too.... in which case a speedi-sleeve might fix it. .....

 

[78mitsu]

could also be a bent housing, the shaft can be strait, if the housing is not it wears heavily on the one side.

 

[waynehartwig]

You sure it's a seal? Could be brake fluid... Taste it to be sure if you aren't.

 

[TooeleBronco]

You sure it's a seal? Could be brake fluid... Taste it to be sure if you aren't.

It looks and smells like gear oil so I'm pretty sure it's not brake fluid.

 

[TooeleBronco]

could also be a bent housing, the shaft can be strait, if the housing is not it wears heavily on the one side.

How would you check the housing? I know it's probably not the axle shafts just because I have replaced them with brand new hardened shafts and it still acts the same as it did before.

 

[Milner]

Which bearings are you using? (one piece or bearind/race seperate) Big or small bearing housing? Be careful when you pull the shaft and try to determine if it is leaking through the bearing, or around it....

 

[TooeleBronco]

its a one piece bearing that is pressed onto the axle and it's the bigger bearing axle.

 

[waynehartwig]

Also verify that the bearing cup isn't cracked. I've seen a cracked cup leaking causing the same effect of a leaky seal.