Wheel bearing problem - need advice

[robertob]

OK this is a long post but I'm stumped!

I got the truck back together the other day (new king pins, added power steering and new axle u-bolts) and took it down to Boulder (12 miles) for a test run. The power steering worked wonderful, it makes it 1000x better to drive (especially parking).

When I exited the highway on some bumpy pavement the front end started shaking back and forth violently. I couldn't stop it with the steering wheel and had to slow down to 5 mph for it to stop. On smooth pavement it was fine. I finished my errand and noticed a scraping noise on left turns. On the way back it was undriveable above 45 mph because the front end was shaking so bad. I dropped it off at my wife's work and took her car home. I noticed that the right front wheel was flopping all over the place.

I came back with some tools and tightened up the loose wheel bearing on the right side, which I thought was the problem. The shaking did not go away so I pulled the power steering belt and drove home slowly. It was better since it did not have the linkage assist to amplify the problem.

At home I jacked it up and found the right king pin was moving all over the place. Turns out the pinch bolt in the axle loosened up. I tightened it again and adjusted the wheel bearing again. The shaking went away but the scraping noise on left turns was still there.

So I pulled the right drum, and it had been rubbing on the backing plate on the top and bottom. I removed the backing plate to check for crap between the spindle and plate, and put it all back. No change. I tightened the wheel bearings beyond where they should be. No change.

After that I pulled the hub/drum again, and checked everything again. The drum is tight between the wheel and hub when the lug nuts are tight, the spindle looks good (there is some tiny scoring on the shoulder for the inner bearing, less than .005 or so). The bearings look good - I knocked them out of the hub and cleaned them to check. No roughness, no discoloration, nothing. Maybe the inner race is a little shinier than I like, and maybe the outer race has some tiny pitting, but I would happily re-use them if I wasn't having problems.

I ordered some new bearings because I have wanted to replace the chinese ones I put in last year but I honestly can't see what is wrong. I did not change anything on that side while I had the front end apart. The backing plate is like 1/8" thick steel so it is not likely to be bent (and I didn't do anything to bend it).

For some reason the wheel bearings are allowing movement of the hub when it is loaded, or at least that's my best guess. I hate to throw parts at it but I can't figure out what else it could be.

[wally426ci]

Did the drum go on the inside of the hub or the outside?

I hear that it is possible to swap that by accident.

[robertob]

Outside, there's no way it would fit on the inside.

New bearings did nothing.


However, I am starting to think it is something to do with the drum and studs. The machine shop that did my studs last time did not swedge them in and the drum is loose like on a modern rear axle. Maybe the drum is moving around behind the wheel???


I'm going to do some more investigating.

[wally426ci]

Mine is a little loose too but not bad.

[Hobcobble]

The drum should be rock solid tight against the hub.
After installing the drum on the hub, it should be turned
as well.
John

[robertob]

I'm thinking the shoulder on the studs is too tall and the lug nuts are bottoming on it, allowing the drum to move around. The machine shop back in CA used longer studs because they couldn't find originals. So I ordered the correct ones (Dorman 160-220) and I'm going to install them.

I'll let everyone know how it turns out.

[Hobcobble]

Be sure to check your wheels for wallowed
out stud holes.
John

[robertob]

Be sure to check your wheels for wallowed
out stud holes.
John

I think they are OK - I was just checking them today. I'll let everyone know what happens after I put the new studs in.

[Txas2step]

Outside, there's no way it would fit on the inside.

New bearings did nothing.


However, I am starting to think it is something to do with the drum and studs. The machine shop that did my studs last time did not swedge them in and the drum is loose like on a modern rear axle. Maybe the drum is moving around behind the wheel???


I'm going to do some more investigating.

So on the d200's the hub is on the inside of the drum? outside on the d100's.

[robertob]

Outside, there's no way it would fit on the inside.

New bearings did nothing.


However, I am starting to think it is something to do with the drum and studs. The machine shop that did my studs last time did not swedge them in and the drum is loose like on a modern rear axle. Maybe the drum is moving around behind the wheel???


I'm going to do some more investigating.

So on the d200's the hub is on the inside of the drum? outside on the d100's.

Same on both as far as I know. Lug - hub - drum. I think you have to get up to the D300s to find lug-drum-hub. And maybe the W100/200?

[Txas2step]

Outside, there's no way it would fit on the inside.

New bearings did nothing.


However, I am starting to think it is something to do with the drum and studs. The machine shop that did my studs last time did not swedge them in and the drum is loose like on a modern rear axle. Maybe the drum is moving around behind the wheel???


I'm going to do some more investigating.

So on the d200's the hub is on the inside of the drum? outside on the d100's.

Same on both as far as I know. Lug - hub - drum. I think you have to get up to the D300s to find lug-drum-hub. And maybe the W100/200?

That's strange? I have (3) d100's from (3) diff. years and all have the hub on the outside. Can someone clarify. None of my FSM have a reference pic. that I see.

[robertob]

You're right, I just looked at my D100 brakes. The drum is behind the hub.

[Hobcobble]

If need be, I can confirm later today that the studs pass through
the drum and then are swedged into the hub..... same as the
D100s.
John

[robertob]

D100 studs go through drum then hub D200 hub then drum. At least my '68 and the '71 D100 parts I have.