Axle/Hub. Do I have a problem?

[mikekaidan]

Sent: 3/25/2008 2:41 PM

I have no idea how long they have been like this, but today I noticed a major difference between my rear hubs. The passenger side is clean, the drivers side is dirty and oily.                                           

I'm getting ready to go on a trip in less then two weeks and really have no idea if I'm looking at something I should worry about or not. I appreciate the imput!

As usual, thanks in advance!

Mike

Rinky Dink
1980 M300 Winnebago Brave

[ClydesdaleKevin]

Sent: 3/25/2008 3:57 PM

Hey Mike,

Just check your differential oil before you go.  Top it off so that it dribbles slowly out of the fill/check hole on your rear axle.  The gear oil you see on your hub is the same gear oil that fills your axle...and it doesn't wash off easily, so it could have been there a very long time.  You may have a very minor leak from the gasket that is under that inner circle of bolts, but unless its pooling on the rim, you shouldn't have anything to worry about.   

That inner circle of bolts is what holds your axle in place, and the plate that it bolts down is the end of your axle.  If you don't want it to leak at all, or for peace of mind, you can unbolt it, smack the center of that plate solidly with a hammer, and your axle will jump out a few millimeters.  You can then carefully pry it out a bit, and the whole axle will slide out once its out about an inch or less.  You don't have to take it all the way out.  Now clean the gasket area if it even has a gasket, and clean all the old gasket off both mating surfaces. Clean it all up with rags and degrease the mating surfaces...then apply a liberal amount of blue RTV sealer where the gasket should be, slide the axle back in all the way, snug the bolts, and voila!  Leak fixed!

Refer to my Budd Wheel album for pics of the axle, nuts, cone spacers, etc, so you can see what I'm talking about...it really is easy.  Brakes, Budd M375

But again, unless the fluid is pooling on the rim, or unless your differential gear oil is very low, I wouldn't worry too much about it...the gear oil in the axle also lubricates the rear wheel bearings in the hub instead of grease.  It isn't the kind of leak that is going to get worse and ruin anything, so if its just a very slow dribble then don't worry.

If you want to fix it now, go ahead...it will keep the wheel cleaner and give you peace of mind...but don't stress out about it if you don't have time now and want to do it later.

Kev

[mikekaidan]

Sent: 3/25/2008 4:55 PM

Kevin,

Thanks for that information! More then I could ask for. If knowing that there is fluid in the differential is all I really have to worry about, I'll stick to that for now. Although, I have taken on the task of "cleaning her up" and painting the rims was on the list. I may have to postpone that one for now. (I really want a set of cheap hubcaps or wheel covers if anybody knows where to get 17.5's... but thats a different post.

Thanks again, and to the guys maintaining this site, GREAT JOB!

Mike

[ZR91]

Sent: 3/25/2008 8:39 PM

For what it's worth, ours leaked a little onto the wheels everytime we used it.-I would slide under and check the level before every trip, and then again when we got to our destination.
Amazingly, the oil level hardly dropped even though it looked pretty messy on the wheels.
I finally pulled the diff cover, sprayed everything liberally with brakeclean and carb cleaner until it was spotless, blew it out with compressed air, reinstalled the diff cover using Permatex "Great Stuff" sealant and filled it up with Quaker State 75-140 full synthetic.

Not a drip or leak anywhere since.

Jay

[denisondc]

Sent: 3/26/2008 5:55 AM

I take the brake drums off my Winnie about each 6 or 7 years, to inspect and clean. I have done it 3 times and will do it again in the next year. Each time I will reassemble the axle shaft to the hub using some RTV gasket maker product, like ultra-black in the tube from permatex. Mine stay fairly clean, not that it would bother me if they oozed a little diff. fluid.

EACH time I have taken them apart I have been glad I did son. The first time I replaced the wheel cylinders and freed up the threads on the self-adjusters. The second time I freed up the threads on the selfadjusters and replaced a broken spring. The 3rd time I put a rebuild-kit into the wheel cylinders and cleaned up the threads on the self-adjuster. (They stiffen with age and lack of use). The next time they will need the wheel cylinders replaced again.

But I know my brake are in working condition. Mine has passed 100,000 miles, and still has its original brake linings - which arent even halfway worn. It has the original drums, and they arent scored to speak of. And after the first time you do it yourself -- it gets much easier to do.

I check the diff. fluid each spring, weeks before our first intended use. I also check the brake fluid level in the reservoir before every trip, and sometimes during a long (multi-day) trip. I dont look to see if it has enough fluid, I look to see if its level has dropped since the last check.

[mikekaidan]

Sent: 3/26/2008 9:14 AM

Jay,

I'm sure this will be obvious when I'm sitting in front of it, but does removing the cover require wheels being removed from the drum or jacking wheels off the ground?

Mike

[ontheroadagain]

Sent: 3/26/2008 1:45 PM

no you can just pull the axle out

[ZR91]

Sent: 3/26/2008 8:18 PM

Mike,

On our MoHo I found it easier to jack it up on both sides of the frame beside the diff, to let the diff hang down for additional clearance to get to the upper cover bolts on the diff.

-You don't have to remove anything except the rear diff cover.
However, it is helpful if you lift it high enough that you can rotate the rear wheels ( and therefore the diff ) to clean it properly

Jay

[75Travco]

This looks to be an old thread, but I would like to add is that in addition to leaking at the axle flange, oil can also be "flung" out thru passages at the hub / brake drum mating surfaces.  There is an "oil slinger" that directs any differential lube that leaks past the wheel seal, thru the opeinings between the hub and the drum.  This feature keeps oil from reaching the brake linings.  So if you notice oil spatter in this area, the wheels seals could be leaking.  Over time the openings tend to clog up, so whenever the drums are removed these passages should be cleaned out, a thin blade screwdriver works OK.