The Stovebolt Site Forums The Shop Area Engine Shop need help figuring out the wobble

I got new outer bearings in my front hubs. (53 chevy 1/2 ton) I put the hubs on and torqued them to the 33# and backed off to the nearest pin whole like the shop manual states. The driver side has a wobble. The passenger side has a small one, but so small I can live with that. So I swap hubs to the other sides, and the wobble stays on the driver side. Any ideas on what could cause it? Its small enough I could drive with it, but it will drive me nuts knowing it's there.

davidn,

As Spock said, something doesn't compute! The only thing that could wobble would be the rotating element which is the hub. If you are indicating that it's the hub that was wobbling, then there must be something wrong with the hub, or hubs and there bearings or races.

I don't know if you are differentiating between wobble and runout. Are you saying you tighten everything up per the book and you can wiggle or move the hub.

There should be no wiggle and there should be no run-out of the brake drum. Anything will be magnified when you stick a wheel assembly on it. I'm not sure how a hub could get distorted to show run-out. If a new bearing were installed and the race wasn't, it would be pretty obvious.

Stuart

seems like it would be king pin/ball joint it a different hub wobbles on the same spindle. seems like it might describe a bad wheel bearing but if the different hub does it to??? i think there is supposed to be a couple of thousanths free play with correct bearing adjustment. sorry, i'm not very familar with this style so i should prob keep my trap shut.

I took the hubs to the shop to look at. If they tell me thay are good, then I'll have to look at the spindles.

David,

If something moves when you turn the hub, it has to be associated with the thing that's turning, the hub. The spindle could be bent like a pretzel but if you could get the hub on it and spin it, it would not indicate any wobble or run-out.

I think you know this, I'm guessing maybe there is something getting lost in translation. My guess is that you are describing worn king pins or spindle bushings. More worn on the drivers side (unusual) than on the passenger side.

This wobble, or wiggle is noticeable when you grab the top and bottom of the brake drum and wiggle them in a vertical plane. The drum and it new bearings are tight on the spindle, but the spindle is loose in the axle or on the pin.

Stuart

Are you watching this wobble with the tire on? If so, you've got a bent rim,
Scott

It's not the king pin. That is nice and tight. There is only movement on the hub when I spin it. At first I thought it was small enough to ignore until I put the wheel/tire on and spun that. It was definitely amplified. Both hubs had the problem, but the drivers side seamed to be worse, even when swapping. That is confusing, so I just took them in and let the shop take a look to see if the inner bearings and roundness is good.

David,

Did you replace the inner bearings?

Tim

The inner bearings were not replaced. That was a thought too. I replaced the outers because one of them had a split casing.

David,

What are you watching that is wobbling? The brake drum is captured with the wheel studs to the hub. I might see the periphery of the drum moving back and forth if it had been knocked off kilter with the hub. The hub itself is a casting and its rough OD may have some run out as it's machined true to ID bearing fits and all other machined surfaces including the brake drum.

Stuart

I wonder if the new bearing races are not seated correctly. That would be my guess. If you can spin a wheel and see a wobble, I would not be driving it that way.

Ok so here's an update. I got my hubs back from the shop. They said that they were worn and had to turn them. They separated the hubs from the drums and marked them so I can keep the pairs together. They replaced the inner bearings. And everything is supposed to be good. I put everything together and I get the same results. The inner races on the inner bearings were not replaced. So swapped those to see what would happen. The runout actually got worse on both sides. So I thought maybe I need to replace those, but the shop says they should be hard enough that they won't wear. So I'm confused as hell, and might just buy new races to see what happens. The shop is confused too. So any suggestions would be great.

David,

When you put the hub on and spin it, where are you seeing the wobble or run out. This is assumed the hub and drum are assembled into a single piece and the bearings are installed and tightened properly.

As the drum turns, where is the run out? I'm talking about turning the drum with your hand, just like a wheel would do as the truck went down the road.

Stuart

I see it on the top of the hub. Now that I can remove the drum, I have tried that, and still the hub without the drum on it has runout. When it is tightened to speck, there is no play in the bearings or the kingpins.

David,

I'm not real sure what you are seeing but the hub itself is a casting and isn't finish machined on areas that are cosmetic only. Are you seeing a rough area that hasn't been machined exhibiting some run out. If you look at a machined area, like where the dust cap fits or face where the drum fits, do they wobble. They should be machined true to the race ID's and shouldn't move or wobble.

Stuart

i still think if you can see it with your eye, it must be pretty bad. i mean to notice it without looking for it. shouldn't you replace the bearing and race in a pair?

yes. I cannot get the race alone. The inner bearings were not replaced. I originally thought that they were. I ordered a set of inner bearings and races. I had the shop look at one of the inner bearings and he just decided to measure it with some calipers. It was not the same thickness all of the way around. So I think this is the problem. we will see.

Did the shop tell you that there was no need to inspect and replace inner bearings on a truck which had bad outer bearings? Or, did you tell them to skip the inner bearings?

Most shops would rightfully recommend replacing both sets of bearings if one set is found to be bad.

They inspected them and said they look fine. I'm not sure how they turn a hub, but they said the inner bearings are good. But they didn't have the inner races. Those were still at home. But I have them replacing the inners now with new races and I'll see what happens.

But they didn't have the inner races. Those were still at home.
I'm just curios how they turned them without the inner races?I thought they needed all te bearings and races to turn em properly?

The brake lathe centers off the outer bearing race ( the pieces pressed in the hub).

What type of bearing is this, ball or taper roller? A ball bearing assembly might have three pieces, inner race, outer race, and ball assembly. A taper bearing only comes in two sections, outer race, and inner race with rollers and cage.

Has the bearings ever spin on the spindle, you will be able to tell if the spindle is galled up. How does the bearing fit the spindle? loose, tight, wobblely....

If you knocked the races out of the hubs before sending them out, then they could be turned wrong, but if the races were still in the hubs, then it should be true if the shop employee new what he was doing.

Do you have access to dial indicator with mag base? You really need to get one and set it up to read the wobble in the rotor face.

You stated in the first post, "you have new outer bearings", why did you change them out? Did they match the old ones? Was there a problem with the old ones?

Joe

Found the problem. It was so simple I was in disbelief. And a couple of you mentioned it. The shop gave me back my hubs with all of the races this time and said that they were checked good and don't want me to waste the money on the inner bearings when I don't have to. (they know I'll spend it there eventually). So started playing with it again. What I was seeing was just a little bit of runnout on the hub and when I put the tire on I thought it was amplified. The shop even said that one is perfect and the other is so small that its not worth fixing. So that's why I didn't believe it was the tire. But decided to rotate through all of the wheels/tires and the problem followed the tire.

So it was it just a bad tire or wheel?

Well. I guess it wasn't just that. There was quite of bit of runnout from the drums being a little warped. The shop fixed that and I just got confused when the wobble didn't go away after they fixed it. they had to separate the drums from the hubs and smooth the surfaces between the two.