Rear Axle Bearing Failure

[jking]

Hi, all - we had just finished 12,000 miles of driving around the "lower 48" when the outer right rear wheel bearing failed on the Interstate. The symptoms are a sudden increase in rpm and zero push - you coast to a stop regardless of engine speed. The pieces tore up the oil seal and all the 90-weight ran out. The heat warped the bearing housing into an egg shape. It takes several days to find the parts and more to install them. MORAL: Check the durned things more often!

[TomW]

Sorry to hear of your trouble.

What kind of vehicle did this happen in?

Tom

[jking]

Sorry - in all the adrenaline I forgot - it's a 1984 310 diesel A/S moho.

[NorCal Bambi]

jking, Been there and done that, On our way to the NorCal rally at San Antiono Lake we lost a rear axle bearing. It started with a subtle grinding noise, then a very loud grinding sound, finall smoke and brake lockup. Great fun. We were lucky and found a place in Holister, CA that had us on the road again after $650.00. All new brakes, bearings ,seals, etc. We made the rally on time and had a great time with great people. We were not the only ones that had adventures going and coming from that rally.
Don

[jking]

That must have been on your tow vehicle. The motorhome is getting a similar treatment but the cost is more llike $3700. Anyway, thanks foor the sympathy.

[TomW]

If you don't mind, what did this place replace for $3700?

Tom

[scottanlily]

hello jking , the rear end in your coach should be a corporate 14 bolt GM .
The most common trouble with them is the rear end lubricant (gear oil) gets
low and the wheel bearings do not get sufficient lube to them ,especially the
outer bearing ,it will self destuct and the whole drum can slide off/or work its self along with the axle since the outer bearing is smaller than the inner bearing .sounds like they are rebuilding the rear end complete ,but sounds very expensive to me ,hopefully you are getting alot more than bearings WOW ! .that rear lube always needs to be full ,the rear hub seals actually begin too leak out the gear oil over time and the level gets low ,then it goes bad from there .Get it checked regularly ,and make sure if possible they actually did check it for you .You may have the larger rear axle assy but still the same applies in regards to the problems and checking of oil.
Scott of scottanlily

[Geophilist]

Scott

How long does the rear end oil last? Should we empty it and replace it all at some point or top off and go? If there is a bit of topping off to do, does that not give you an indication of something leaking out somewhere?

Steve

[jking]

The job is done - they had to replace the entire rear axle - banjo and all - the heat had warped things beyond repair - also got a new tire into the bargain - amaybe the cost wasn't excessive considering all that - anyway we're back on the road.
'84 310 turbo diesel
jamie

[scottanlily]

Hello Steve ,

Late getting back to you as i don't always get back to the threads I post on as fast as I like .The answer is that if the rear diff lube is any color other than the gold / caramel look ,change it .If its low it does indeed mean a leak ,usually thru the hub seal into the drum ,common problem .again if it
gets low enough ,destruction is immenint as in jking's case ,bad news .When the gear oil does get into the drum ,it gets all over the shoes rendering them
pretty much useless .Just keep on top of the rear axle maintenence on these
motor homes ,thats the important thing .jking's rear diff surely had no oil
left in it ,and whatever was burned up as well. In any case ,if low at least
top it off so its always full ,thats critical to the life of the differential and
the wheel bearings.

Scott

[ROBERTSUNRUS]

Hi, along with leaking axle seals, I think, more common is leaking pinion seals. Pinion seals may leak very small amounts of oil; And spray it all under the vehicle, therefore only leaveing a few drops here and there to be seen or ignored by the owner. Finally, when the oil level is low and you're on a nice long trip, Murphy's Law kicks in. Differentials are seldomly checked because they don't have dip sticks and are pretty much maintenence free.

Bob

[Geophilist]

Scott,

Thanks. I think I will go out and check the oil level. I sure don't need a $3,700 "payment" on the MoHo anytime soon.

Steve

[GlenCoombe]

When changing the differential fluid you may want to consider going synthetic. Those who have tend to testify about the superior lubricity (is that a word?) lubroisity??.. whatever, it lubes better.
Considering the time between rearend oil changes.... if you've ever done it.... the better we can justify the added cost of synthetic.
I'm in line for a rear pinion seal and synthetic.

[scottanlily]

I just did my services on some 2005 chevy one tons for a customer of mine .
The 5 1 ton GM trucks have about 50 000 miles on them now .They carry granite and corian for kitchens and such .truck 24 had dark brown rear end oil and an oil seal leak at the rear hub as well .It was definately time for a service .The fluid had gotten low as well ,but no damage to any bearings or anything as it had not gotten that far .I had done the rear disc pads a 35000 miles, no issues then .It can sneak up on you is my point so keep an eye on those rear diffs and oil level .

Scott

[guy99]

Originally Posted by jking

Hi, all - we had just finished 12,000 miles of driving around the "lower 48" when the outer right rear wheel bearing failed on the Interstate. The symptoms are a sudden increase in rpm and zero push - you coast to a stop regardless of engine speed. The pieces tore up the oil seal and all the 90-weight ran out. The heat warped the bearing housing into an egg shape. It takes several days to find the parts and more to install them. MORAL: Check the durned things more often!

Jamie,
Just wanted to say thanks for your heads up. Had my 1984 310 Limited in the shop after an 8,000 mile trip to New Brunswick and back. Because of your post I specifically had them check the differential - they found (and replaced) a leaking pinion seal.

I may have dodged a bullet - thanks again.

Guy