Unexpected wheelbearing failure (1 Viewer)

[Cruiserdrew]

I developed a leak between my third member and the front axle while travelling home from Death Valley. Other than stopping every 50 miles to add gear oil-thanks Echo29 and Darwood- it went fine and I didn't cook my R&P. I only had to work until 2pm today and so got a chance to tear into it so I could pull the third member. I found this failure of the outer bearing race on the driver's side. The wheel was spinning freely, made no noise and was normal in all other respects. This picture is of the race, the bearing itself looks normal, and if it were not for the race, I would reuse it with no question.

I had called CDan this morning to overnight me the knuckle rebuild parts (since it would be apart anyway) and he said "Do you want wheelbearings too?" Of course I said no thinking they would be fine. Shait-now I have to scramble around town tomorrow and find at least the outer bearing. If AutoZone has the Timkins all in stock, I'm buying a full set. Otherwise it's more overnight parts from Dan the man. So the moral is that if Dan asks do you also want any other part, just say yes.

The maintanence history is that these are OEM Timkin wheel bearings, repacked at 45k, and 70k. The 70k grease was Amsoil, so I'm going back to Mobil1. I now have 93K on the 80 series. I guess I'm curious if anyone else has had a similar failure, and what the cause might be.

 

[Junk]

When did you notice the leak and exactly where was it ? Seems like it would have been easy to never notice at all unless it was dripping in the driveway, so on the road just surprises me. Good deal on spotting it though.

 

[Jim_Chow]

How could they fail so early, unless they suffered major water intrusion? My Koyo's in my '86 are still original, first repack done at 102K, then at 130K (Valvoline moly) and 168K (Amsoil red MP). Does this suggest I shouldn't have used Amsoil red?

 

[IdahoDoug]

Yeah - where was the leak coming from? I'm trying to figger how this was related to a gear oil leak and can't manage it.

DougM

 

[NorCalDoug]

I was on the same trip with Andrew.
He first noticed the leak as we were getting ready to drive home from Death Valley. He was in the parking lot of the visitor center. The previous 4 days were spent on the trail, so a leak would not likely have been noticable.

Well...that explains the why...I wonder what the cause was.

 

[Cruiserdrew]

The wheel bearing thing was unrelated to the gear oil leak. I have it all apart to replace the gasket between the axle and the third member. The upper bolts were loose when I checked, so perhaps I didn't tighten them enough when I reageared last year. The gasket itself was torn and allowing oil to egress between the housing and differential. The wheel bearing thing was weird, and as I said, unexpected. I agree about the bearings-the wheel bearings on my FJ60 I'm sure were original when I replaced them at 180k. All the other bearings on the truck look normal. I'm thinking no more Amsoil, but who knows?

edit for Junk-I noticed the problem just before we hit the highspeed road to come home. It took a few ounces the first time, then 1/2 quart 50 miles later. At that stop i gooped some permatex in the area of the leak which slowed the leak about 90%.

 

[IdahoDoug]

Also, which Amsoil grease? Was it the moly fortified GHD dark purple? And was there any grease left in the hollows of the rotor? In extreme heat, this "extra" grease is supposed to melt and flow into the bearings.

DougM

 

[Cruiserdrew]

Also, which Amsoil grease? Was it the moly fortified GHD dark purple? And was there any grease left in the hollows of the rotor? In extreme heat, this "extra" grease is supposed to melt and flow into the bearings.

DougM

Yes-the same grease I used on the knuckles. It's the moly fortified Amsoil. The grease itself looked fine, still purple and the center cavity was full, just like I left it. I did hit a rock pretty hard 1 year ago on that side, but otherwise it really hasn't been abused. It was strange that the bearing looked so good with the race looked so bad.

 

[Junk]

Well, glad you have things under control. So if you hit a rock a year ago, then I guess that dispells my belief that there is no rock in CA eh?

 

[RavenTai]

The general discoloration (besides the pitted area), is it corrosion, heat or not clean? Looks like heat to me but hard to say for sure from the pic.

Have about 20K on the bearings in my Mobilgrease 28 experiment, no problems yet.

 

[Cruiserdrew]

Well, glad you have things under control. So if you hit a rock a year ago, then I guess that dispells my belief that there is no rock in CA eh?

The rock I hit was in Nevada. There are no rocks here in California. You wouldn't want to live, wheel or even visit here. Nothing but flat featureless sand for many miles in all directions. Beyond the sand is salt water mud. Beyond that is Mexico. New Jersey is much better in all respects especially the favorable 4 wheeling terrain. I wish I lived there.

 

[Junk]

The rock I hit was in Nevada. There are no rocks here in California. You wouldn't want to live, wheel or even visit here. Nothing but flat featureless sand for many miles in all directions. Beyond the sand is salt water mud. Beyond that is Mexico. New Jersey is much better in all respects especially the favorable 4 wheeling terrain. I wish I lived there.

Yup. Kind of figured that.

 

[Tools R Us]

That type of failure is called spalling, typically caused by a defect in the race or debris chipping the surface. Carefully clean the inside of the hub to remove the bits of hardened race and install new bearings, good to go!

http://www.timken.com/products/bearings/services/valueadd/damageanalysis1.asp

http://www.emersonbearing.com/fail_normalfatigue.htm

 

[IdahoDoug]

Interesting. I was wondering about the grease type because there has been some sentiment that moly and high speed roller bearings do not mix. It was speculated that the moly could cause a roller to not have enough friction to roll, then create a flat spot on the roller. This does not appear at all to be that type of outcome as that scenario would damage rollers, not the race. You have quite the opposite of that posited outcome, actually.

I just bought a couple tubes of the GHD to top off my steering knuckles which I packed with it a while back. Since I'm also about to repack the wheel bearings on the other truck I was thinking about using it like you did on the wheel bearings. Hmmm. I've just picked up a bearing packer for the grease gun.

DougM

 

[Cruiserdrew]

The Emerson link posted by Kevin is interesting. From the pictures, my failure looks like contamination-so perhaps some crud got included at the last repack. The bearing does not look overheated, which would be my second expectation. It could also be "normal fatigue" per the Timkin link. I always aim for a preload of 10, and check after tightening the outer nut. This time I'm aiming for 8. Robbie often talks about the bearings loosening a bit after 10k or so, which is why I've always aimed for the top of the spec. I'll go midrange and see what happens. I do know if the bearings are even a little loose, the spindle gets chewed a bit-I've seen that on another 80.

 

[cruiserdan]

Your package, less wheel bearings , Arrived in Sacto and 05:15 this morning.....

 

[Rookie2]

Yes-the same grease I used on the knuckles. It's the moly fortified Amsoil. The grease itself looked fine, still purple and the center cavity was full, just like I left it. I did hit a rock pretty hard 1 year ago on that side, but otherwise it really hasn't been abused. It was strange that the bearing looked so good with the race looked so bad.

There have been previous discussions about not using moly fortified grease for the bearings. May not be the root of your problem, but you might consider sticking with the grease specified in the FSM here. Moly fortified in the knuckle, lithium base NLGI No. 2 for the bearings.


Rookie2

 

[semlin]

I understand the theory behind not using moly grease, but I notice that Redline sells their moly fortified grease for use on wheel bearings. what would they know that amsoil et al. do not?

 

[landtank]

I understand the theory behind not using moly grease, but I notice that Redline sells their moly fortified grease for use on wheel bearings. what would they know that amsoil et al. do not?

that there are suckers born everyday.

 

[ginericLC]

I would not use Redline Grease with Moly. I did in my 91 and suffered a wheel bearing failure some 5k miles later. No water contaimination. No leaky axle seal or anything else. I use the Amsoil grease now and had before Redline and although I don't swear by it I do like the results. I use the red (non moly in the wheel bearings) and the purple (moly) in the knuckles, u joints, etc... Low speed applications. I believe the Toyota FSM specifically specifies a non moly grease in the wheel bearings. Not that they say non moly but they don't specify moly. Whereas on the knuckles they specify moly. I haven't looked at it lately so I should probably refresh before I try to quote the FSM exactly. I've read, no experience other than the afoementioned Redline Moly wheel bearing catastrophe, that moly grease is too slippery for wheel bearings and allows the bearings to slide without the rollers rolling. Since I can't crawl inside and actually see the wheel bearing as it spins going down the road I don't really know. And just so you don't think I'm an anti Mobil 1 or anti Redline advocate, and only pro Amsoil. I run Redline Gear lube and ATF in my 94 and I ran Mobil 1 oil exclusively in my 85 V8j60.

Jim I would not be concerned about the grease in your 60. One if you did it right there should be no problems. Also you don't have as great of a risk of a leaky axle seal because of the part time nature of a 60 series. The seals wear very little on a part time system. Actually, I've never heard the problems in 40, 55,60, 62 etc... with front axle seals like 80 series.

Anyway, just some more thoughts. Take em or leave em.