Greasy brake shoes??

[JoeCanada]

I noticed some fluid oozing from the back of one of my rear drums, so I popped the drum off (thinking it was the cylinder), and found the shoes, drum, everything all coated with a layer of what looked like black grease. The cylinder looked ok.

I wasn't sure what it was, but my dad suggested maybe the axle seal went. Does this sound correct?

 

[KELLY88]

Ya sounds like a leaking seal. The drums should not have any oil of any kind in there, it would negate the very purpose of the brakes. Was the fluid just oil or was it a mix between grease and oil?

 

[JoeCanada]

It looked and felt like a very thin grease, or a thick oil.

 

[MAKG]

Remove the drums and check the axle flanges for side-to-side play. A common cause for this is a failed axle bearing eating into the axleshaft. It's VERY dangerous; the end state is the a back wheel falling off (along with the drum).

To repair a failed axle bearing, you need a bearing and usually an axleshaft as well.

 

[KELLY88]

Wouldn't a failed bearing make some kind of grinding noise?

 

[MAKG]

Wouldn't a failed bearing make some kind of grinding noise?

One would think so, but having had this happen before (on a Bronco II), it isn't THAT different from road noise on cheap tires.

 

[metalmacguyver]

I had a rear axle seal fail. There was no play in the bearing. It was just a seal that aged and failed.



FYI!!!!

The idiots at the auto parts store will try to give you the axle seal for a 31 spline explorer axle which is too big. You need to ask for the axle seals from the 7.5" axle to get the right ones. The 28 spline 8.8 and the 7.5 have the same size seals. I found out the hard way when I went to get the parts and had to make another trip.



EDIT:

Dont forget to replace the brake shoes and use lots of brake cleaner to clean all the gunk out of there so that the new shoes dont get recontaminated.

 

[JoeCanada]

I'll check for play when I get it home. I called the auto parts store to get a price on the seal and bearing, and they needed to know the axle size. How do I determine that? Or is it a 7.5 inch axle no matter what?

On another note, how difficult is it to remove the axle from the diff? The Haynes manual isn't too specific on the entire procedure. It'd be nice to know how much time I need to budget for this job.

 

[MAKG]

It's not very difficult, but you have nearly even odds of breaking the FN toothpick crosspin bolt. THEN it's an exercise in creative swearing.

It IS messy, as the axleshafts are secured inside the differential carrier.

 

[JoeCanada]

Well I checked the axle for any bearing play, and there is virtually no give, no matter which way I pull it, so I can assume that the bearing isn't destroyed, just the seal. Now I just have to figure out which seal I need. (For a 7.5-inch axle, correct?)

And just to confirm the (theoretical) removal of the axle: Remove diff shaft lock-bolt, remove pinion shaft, remove C-lock clip, slide axle out.

That simple? (Assuming nothing breaks)

 

[MAKG]

That's the cross-pin. The pinion shaft is something else, and you do NOT want to remove it.

 

[metalmacguyver]

Yes it is that simple.



The 7.5 and 28 spline 8.8 use the same size axle seal. The 31 spline 8.8 uses a larger seal. Just ask for a 7.5 axle seal and you will get the right one. If you ask for an 8.8 seal (you do have an 8.8 BTW) you will be given a seal for a 31 spline 8.8.

 

[Sasquatch_Ryda]

That's the cross-pin. The pinion shaft is something else, and you do NOT want to remove it.

Lots of books refer to the cross shaft as being a 'pinion shaft'

 

[JoeCanada]

That WAS extremely simple...once I got the damn plastic diff cover off. And the boneheads at the parts store DID give me the wrong seal (too big) at first.

One last question: what kind of loctite should I use on the lock-bolt? (Red, blue?)

 

[MAKG]

Blue. Maybe even green.

With red on there, you WILL break it the next time you take it off.