The Stovebolt Site Forums The Parking Lot Big Bolts rear axle bearing configurations

Someone out there must have run into this: I'm working on the rear axle for the 58 2.5 ton I'm repairing. I've got the 58 repair manual which describes in pretty good detail the process of disassembling, repairing and reassembling the hub, incl. bearings and seals. The manual shows the outer bearing as being held in place by a snap ring, but no snap ring on the inboard bearing. In actuality, the hub I just disassembled has a snap ring at the inner bearing, but none at the outer. What could explain this? Also, I was surprised to find that the inboard bearing uses the axle housing as the inner race, and in fact is only a 'partial' bearing consisting of a cage and rollers. That tells you that this is the first time I've looked at the innards of this type axle.

Some of the 2 ton used a snap ring on the outer wheel bearing for the cup to bottom against. A 2 1/2 probably would not have this snap ring. The cup merely bottoms against the hub. I have never known the inside bearing to have a snap ring. I also don't understand your description of the inner bearing. It looks just like the outer bearing, only larger. The cage may have broken and part of the cone stuck to the axle housing. When bearings fail, they spin on the housing and generate heat. This may have been your problem. Can you post a picture of what you have.

Thanks for the reply - yes, I'll get a pic or two. What's amazing is that there is no evidence on the housing that a race had been there - in fact the housing is smooth with a perfect concave to match the bearing rollers. Also there is no uneven or jagged wear on the bearing cage/rollers. The snap ring appears to be placed such that it overlaps the inner end of the rollers just enough to keep them from falling out - then when the snap is removed the rollers will actually fall out separately. But it still doesn't seem right.....

Is this possibly the wheel end you have?

https://picasaweb.google.com/crenwe...PY0kcQAaoHTYQnVEc4wA#5574451262824572162

No - that's not the one - I have some pix I was going to send you, but I didn't realize there's not a direct way to post pix on this site. I don't subscribe to any pic hosting sites....

email them to [email protected]

Sounds like he has barrel bearings.

I'll email the pix this evening. I took another look at the bearing setup today. It looks like the bearing is just plain different. Unlike what I said I first saw, there is an inner 'race' of sorts - it's much wider than the bearing cone and is really 'pasted' to the axle housing with no normal means whatsoever to remove it (no notch, gap, etc). And, to clarify about the snap ring - it is part of the bearing assembly and is not part of the hub. Look at the picture of the inside of the hub - you'll see the snap ring groove. The groove is formed in the bearing cup, not the hub. The snap ring serves as part of the bearing cone, holding the rollers from completely falling out when the hub is pulled. None of this would've surprised me if the '58 Shop Manual had any info about this type bearing - but it doesn't.

I looked at the pictures. I also looked in a GMC service manual. They are usually more complete than Chev. I still think it is the same setup as the GMC 370. It was a kind of in between size between the 2 ton and the larger trucks. The part that is on your axle stub has to be part of the bearing cone. However, if a bearing went out at some point in time and spun on the housing, someone may have pricked the housing with a center punch and drove the bearing on to keep it from spinning. I even remember bearings getting so hot that they welded themselves to the housing and I had to torch them off. Or someone may have put Loctite on the cone to keep it from spinning. I have seen some Hyatt bearings that the seal actually rode on the bearing cone. This may be one of them. Unless the rollers, and I am assuming they are barrel rollers instead of tapered rollers, are bad, I wouldn't disturb the part that is stuck to the axle housing. It could be a very difficult bearing to find.

Thanks for the feedback - yes they are barrel rollers. I agree about replacement - sure they are somewhat worn, but it's an even wear and to an extent they are adjustable. I could spend a lot of time and money and maybe do some damage trying to replace them.

You just wanted to know what the setup was or do you need to replace them.

Mainly, I was just figuring out the setup. There is some wear on the bearings, but at the going price, and considering the truck will not be run hard, I'll probably use the originals. The main thing I'm replacing is wheel cylinders and seals.

Yes Barrels are very expensive and some are no longer serviced, I haven't yet had to do a cross to see if they can be replaced by something else, I would think so, also they seem to adjust a little bit on the loose side compared to timkens, I learned the hard way several years ago and ran a set up and backed em off as normal and I burned them up.

When you mention about proper tightening of this type bearing, I want to make sure I get your point: are you saying don't overtighten them? I notice the shop manual recommends to back off 3/4 of a turn. By the way, I forgot to mention in earlier posts: of the many oddities of this bearing, one is that the rollers ride OUTside of the cage, not inside like most - and they are not an integral part of the roller cage - rather, they are INDIVIDUAL pieces. For those who haven't seen one of these bearings apart, you almost have to see it to believe it....once I cleaned and inspected the components, I 'glued' the rollers to the outside of the cage with cold thick cup grease; set it in the cup; then installed the snap ring which holds the rollers in the cup; then installed the new seal. Then when the hub assembly is installed, the lesser portion of the rollers which project thru the cage, ride on the separate inner race which is on the axle housing.

Well I didn't back off quite that much and lost a set, so 3/4 of a turn sounds about right, maybe just a touch more.