Wheel hub leaking grease?

[rluhr]

Take a look at this. I just towed 1500 miles and all was fine until sometime in the last leg, when I spotted this (see picture).

The hub has always run very cool. It was re-packed in the past two years by prior owner. But does this splatter of grease mean the seal is blown, or is it possibly just an innocent blob of grease that jostled loose?

[rluhr]

And here it is with the hubcap removed.

[markdoane]

I don't think it is a seal. The seal is on the back side of the wheel. You should take the wheel off and see if there is any grease on the back side.
The grease you're seeing may be just a little leakage around the hub cap. Pry off the hub cap, check the bearings, and repack, it's normally a once a year thing anyway.
When you repack the bearings, you need to put a new seal on the inside.
Here's a poop sheet on packing the bearings. Bearing repack
Read about halfway down.

[john hd]

looks like some grease got by the dust cap.

i agree with mark, you should take a look at the back.

here is a link for timken's home page, click on tech tips for more info.

http://www.timken.com/products/bearings/

john

[davidz71]

I replaced bearings on all 4 axles last summer. When I pulled the bearing caps off 3 of the 4 axles, the caps were full of fresh grease. There was some oil stain around one hub but none of the others. It could just be a case of stuffing way too much grease in the axle and when the hub area heated up some of the grease was displaced. On the other hand, have you checked to see if the axle nut was tightened down more than it should be?

[markdoane]

Good point, Craig. If overfilled, the grease has to go somewhere when it gets hot!

[davidz71]

I'd clean up the excess grease if you haven't already and check it out during your next trip.

[rluhr]

Good thoughts, all. I haven't checked the axle nut yet but I am 1500 miles from home without my torque wrench. The hub could be overfilled. My next trip will be only 100 miles, passing a half dozen RV shops along the way, so I think it will be safe to take the advice given: check the backside of the wheel and then, if I don't find a huge leak, just clean it up and check it on the next trip.

[Inland RV Center, In]

From the posted photo, it appears that the grease cap, is threaded on and not pounded on like the later models.

If that's the case, any deformity in the threads will cause it to leak.

The bad news is that a replacement is not to be found.

I would suggest that you removed them, and install teflon tape on the threads and reinstall the cap. You may have to use two or three thicknesses, or more, depending on the damage to the threads on the cap.

That should take care of the problem.

Andy

[wb13798]

i concur andy. the cap has to be damaged.

[rluhr]

Well, I took off the cap and here's what I learned.

Andy was right -- it is a threaded cap. The threads looked OK but they were undeniably leaking a small amount of grease. The hub was not overfilled, there was plenty of air space.

I did not find any other evidence of damage or failure. Without a torque wrench I was unable to verify the tightness of the axle nut. I put teflon tape on the threads, as recommended and re-tightened the cap. We'll see how it performs. Thanks for all the advice.

-- RL

[john hd]

you did back the nut off one notch after torquing it....right?

there should be a little play in the hub.

john

[rluhr]

I didn't do anything to the axle nut yet. The prior owner re-packed the bearings and he torqued the nut. But I'll check for play -- didn't know about that.

-- RL

[john hd]

oops

sorry r.l. i misread yer post, was in a hurry, check the timken link above it shows the proper technique.

john