Hub Seal Leaks

[Jon Wehrenberg]

This is intended to show everyone why hub seal leaks have the potential to be a big deal. Apart from the cosmetic issues hub seal leaks will lead to loss of braking and ultimately seized bearings, both of which can ruin your day.

The pictures below show how brake shoes (or discs) get covered in gear oil, and the brake drum also gets coated effectively eliminating the friction between the braking parts.

Every time a coach is serviced whoever is responsible should shine a flashlight at the rear side of the wheels and brake area to look for signs of leakage. As an owner pay close attention to any visble signs of grease or oil on or behind the wheels visible through the holes around the perimeter of the wheels.

It is significantly less dangerous and expensive to fix a hub seal leak when first noticed than to wait.

[hobobimmer]

The pictures below show how brake shoes (or discs) get covered in gear oil, and the brake drum also gets coated effectively eliminating the friction between the braking parts.

Jon:

Based on those pictures, it looks like you have some serious work to do cleaning up your bus before departing for Spearfish. Doesn't seem consistent with your typically high standards. I've never seen anything like what is shown in those pictures. Wow.

Perhaps you should invite Deb over to have her show you how she can degrease almost anything. I know our things (whatever those things are that are in your pictures) are way cleaner. She has a nifty cake icing spreader which she uses for degreasing and scraping thick grease like you found on your bus. Let me know if you need her to come over and we'll see if she can fit your degreasing project into her relatively busy schedule.

For any of you who ever goes under his/her bus and finds grease and wants to scrape the grease away, see Deb in Kerrville or Spearfish and she'll give you one of her nifty scrapers. I think we only have 27 left, so catch her early. We'll have two for Jon.

eric faires
huntsville, TN

P.S. Deb said Jon is now going to smear me for playing with him.

[merle&louise]

Eric,

I would be MM mustache that the brake shoes and drum in the picture are NOT Jon's Liberty. That has to be someone else's coach. A-1 would never have his baby looking like that!

[adamdegraff]

Jon,
Another very helpful post. Thanks for taking the time to share!

Adam

[Jon Wehrenberg]

I have not named names, but the people who paid serious dollars to maintain this coach may have had a chat with the company that had that responsibility and failed in doing so.

As owners we don't necessarily get under our coaches. We entrust others to do that, and missing a grease fitting is an oversight. Letting a coach with such an obvious problem go back to the customer without repairing the problem or even telling him of the problem goes far beyond a simple oversight.

So the next time you see a wheel with streaks of grease radiating from the hub area this could be what it looks like when parts are disassembled.

As our resident expert on grease cleanup, Deb Faires, can attest there is no way this particular drive axle brake could have had any effectiveness. Also, this leak had not just started. It had been leaking for miles and miles. The cost could have included ruined bearings, seized bearings and the thousands associated with a differential stub repair, ruined brake shoes, or worse an accident due to compromised braking.

[normancasson]

when this mess is cleaned up and new brake shoes & seals are installed the tech also either needs to pack the bearings with grease or pre-load that side of the axle with 90w to make sure there is proper lubrication when you leave the repair shop. As a few of our fellow POGers can attest how about doing all this work and 10 miles down the road have the bearings seize and then need a REALLY expensive tow back to the same shop for a much more difficult and expensive repair.

[Jon Wehrenberg]

Good catch Norm.

This deserves caps:

IF YOU HAVE YOUR HUB SEALS REPLACED ON THE DRIVE AXLE, AS NORM POINTS OUT, PACK THE BEARINGS WITH GREASE OR TIP THE ENTIRE DIFFERENTIAL TOWARD THE NEW HUB SEAL SO OIL FILLS THE HUB.

If you have someone do a drive axle hub seal replacement make them prove the bearings are sufficiently lubed before the coach is driven. State up front before the repair begins that you want verification so the mechanic understands clearly that this is a critical part of the repair.

Front and tag axles just need a visual verification that the lube is at the correct level.

On this repair we did both to insure the bearings received sufficient lubrication before it was put back into service.