Eric Fraser

Last summer I felt a slight play at the 12 and 6 o'clock position on my rear wheels. I picked up a pair of rear wheel bearing units at Pep Boys. I understand that these units are identical to the OEM units. And in fact when I compare the old one I took out to the new ones, it is clear that they are the same. In any case, I replaced the left one. I checked for play and would you believe it, the same slight play at 12 and 6 was still there. In disgust, I shelved the second new unit and kept driving. Other than the slight play at the wheel, there are no other symptons whatsoever. No whining, no clicking no noise when going straight or turning in either direction.

Now I need to register my car in Maryland where they have this pesky detailed safety inspection. I took it in for inspection at the local dealer today and they failed it. Said that both rear wheel bearings are worn. They want $1,000 to replace them. Yeah, right. So here are my questions:

1. Could some looseness in other suspension components produce this play and mimic a worn rear bearing?
2. Do good rear wheel bearings really have absolutely zero play?
3. Has anyone else replaced their rear wheel bearings and had the play remain?
4. Has anyone got what turned out to be a bad rear wheel bearing unit from Pep Boys?
5. Is there any way to test the new unit on the bench before I spend my entire weekend on my back for naught?


[Modified by Eric Fraser, 12:26 AM 10/13/2001]

88L98

did you torque down the three t55 torx bits and spindle nut properly? the new bearing should have no play at all. i dont believe there is anything else that would cause the movement at 6 and 12. i had it in both of my rear bearings, and the new bearings i put in made it tight as a drum.

Aggravated4life

If it helps, I replaced the rear bearings on my 86 with pep boy units...I STILL had the same tiny 12 and 6 O Clock play as before...however I have NO problems with the bearings...no noise and smooth ride.

I couldnt see any other suspension play causing it to slightly move in that area.
But you could very well be moving the spindle as well a tiny bit making it look like bearing play.

Its not going to be easy to convince the inspection shop that some tiny movement is normal....looseness or excess is not.
If you have new bearings on, they will see it and show them the receipts and inform them that these bearings are fine.

You may want to try another inspection station...Id hate to see you have to replace them again and find they are the same thing.
I did both my rears the same day and they both have the same amount of tiny play in them that I accepted as normal.Has not caused a problem for 2 years now.

Cant believe I got 2 defective bearings from them...and besides a guy who emailed me about the pep boy units told me the same thing...
He had that tiny play as well.
Just be sure yours isnt loose and wobbles.

Inspection sucks...im glad I live where they dont do these things anymore.It seems they look for things to be bad just to fail you up front.
Been through that in NY many times before.
They tech was a moron and didnt know what he was talking about.

Eric Fraser

Thanks Bill,

I think that I'll try another inspection station first. I wish the state safety inspections were done by disinterested third parties. As it is, the repair shops have a vested interest in failing your car so that they can offer to do the work.

Other than the play at the wheel, what are the usual indications of worn rear wheel bearings?

Eric Fraser

88L98,

Well, I don't own a torque wrench yet. But I am sure I snugged those three torx bolts and the spindle nut down pretty tight. Where did you buy your bearings?

Aggravated4life

Eric,
The only time Ive known a bearing to be bad was when it really clicked and rocked when testing it for play.The other is when youre driving and can hear it grinding or clicking loud around turns or even going straight.

It seems to be that not all wheel bearings are alike...manufatcureres tolerances and clearance issues and etc.
I needed new bearings on my FWD Lumina, which is very similar to the Vettes set up.Going around turns,you could hear it grinding,but when on jack stands off the ground there was no movement at all.
Even the new bearings i bought from autozone, which were perfect and fixed the problem, did not rock at all either.
Didnt have that tiny play my rear bearings have on the Vette.

When I worked at a GM dealer, and did a few bearing jobs,(sealed hub units that is) some still rocked a tiny bit and some did not,but they were never a problem on the road test and never came back for any complaints or noise.
These were always a/c delco units too.

Believe me everything was tightened and torqued to specs.
If you suspect the bearing you bought may be defective and have too much play, exchange it for another unit.

But it seems to me that some bearings are just built a tad bit looser then others,but arent ever really a problem.Some dont even move at all, some do a tiny bit.

As i stated,If theres more then a few MM's of play,excess looseness feel, and it wobbles or clunks/clicks loudly,then its out of round/bad/or defective.
A good road test will confirm even more if any noise or not.

bogus

I really hate the MD inspection... I live in DE, but gee... I hear nightmares about rip offs from those so-called inspection stations.

take it to your local trusted mechanic... THEN take it to the inspection station.

If you feel there is a rip going on, take it to another inspection station. I would start a campaign to get this shop shut down!!!

corvette90

hi

same thing here..

a little play, just enough to feel,bearings are new...
no noises at all..

h rocks

Eric, to beg the obvious question, is it at all possible that any of the play being felt is because there's a slight bit of torque/twist being applied as the 12&6 "test" is being done? If so, it's very likely that what they are feeling is excessive play in the toe rod ends. I replace my hubs/bearings regularly because I run my car on roadcourses, and the lateral g's place a very heavy load on those little bearings that are sealed in the hubs. I never feel any play when done with the installation of new units. I have run the Pep Boys units, and the ones that I got were in fact manufactured by New Departure Hyatt. (The former GM division spun off a number of years ago.)

Here's a long shot...I guess it's *possible* to feel some vertical play if the trailing arm bushings are totally gone, but my guess is, highly unlikely. The bottom line is, there should be no measurable play when the new units are properly installed.

Eric Fraser

h rocks,

Thanks for your input. The bearings I got from Pep Boys were made by CR (Chicago Rawhide?). I wonder if the brand makes a differennce as was suggested earlier? I was also made to understand that CR makes all the bearings for the vette.

Aggravated4life

Hey Eric,
If anything,H rocks has some of th best suspension advise ive seen on this board..and I also just realized your mileage as well..maybe you do have some other suspension movement,like maybe the rear knuckle is moving a tiny bit and its not the bearing.

but Because of differences Ive seen in brand names,I just never took them as all being rock solid..however I will admit with my car, after I changed all the rear bushing pieces, the rear is tighter then before as far as movement goes..all my bushings were flat and dried out and that can cause a few mm of play between adjoing parts.
The back wheels didnt "click" or move much after I changed the bushings out, which could be taken as a bad bearing by some shop.

Is there any way you can look around the back of the tire while someone attempts to rock the wheel?See if any play someplace else?

Id hate to see you fail inspection for another movement that "appears" to be the bearing but is not.
Be sure to recheck all the torque settings again as well just to be sure.

Also check to see if the 2 trailing arms that hold the knuckles arent twisting sideways in the wheel well.

Im beginning to wonder now if CR bearings are indeed made a certain way or something else was making the movement.
Keep us posted on your findings.

h rocks

Eric, the "CR" brand is simply a marketing name. The actual manufacturer is "NDH" as mentioned before. The big difference in the PB hubs is that they have a lifetime warranty, and the price is about half of GM Goodstench retail! (Even if they were made by Timken, they would be at least as good as the NDH units. Timken is the OE manufacturer of many sealed units, as well as one of the premier roller bearing manufacturers in the world.)

Lv2Driv

pick up new vette magazine the anniversary issue
has an article on replacing the rear bearings.
The issue has a yellow C5 tigershark on the cover

lemans396

What about the ones in the MAD catalog? On the same page as the AC Delco units they have "Top quality U.S.A. made bearing assemblies". They list for $159.95 for the front and $169.95 for the rear. I'm looking for front and rear and the AC Delco price is ridiculous. Would it be a bad gamble on them? I mean they are not made in China or anything like that.

Fla96LT4

FYI...........I just purchased two rear bearings from Autozone and they are $120.99 each. Made by Timken and appear to be first class manufacturing. Fixed the problem I had (12 o'clock to 6 movement).

Cruz 86

I had play. Replaced rear bearings. Still had play. Installed new polyurthane bushings in camber arms. No more play.

Eric Fraser

So last week I replaced the right rear hub/bearing with the unit from Pep Boys that I had sitting on the shelf since last summer. Again, I felt a slight play in the wheel after installation. I took the car back to the dealer for a re-inspection today. I explained to the tech that the right rear hub/bearing was brand new and the left rear only had 3k miles on it. He failed it again. Said that the bearings must be cheap aftemarket units not built to the proper tolerances. He suggested that I buy OEM units instead. Quoted me $435 a piece.

Since the Pep Boys set came with a lifetime warranty, I figured I might as well try for another set. All I have to lose is my time and sweat. So I called Pep Boys and explained the situation. They implied that there must be something else wrong. A brand new bearing simply should not fail. Could it be a worn spindle causing the play, they asked. He suggested that I pull the bearings again and bring them in to see what the manager had to say. I don't know what he expects to see. Externally, the ones that I pulled out with 166K miles on them look just like the new ones, just a little dirtier.

So before I spend yet another weekend on this problem, I have two more questions:

Has anyone installed the Pep Boys rear bearings on their car and had absolutely zero play at the wheel?

What are the chances that a worn spindle could mimic the symptoms of a worn hub/bearing?

Fla96LT4

Eric.........I used the Autozone (Timken) bearings and all 12 - 6 movement went away. I also had a bad support rod bushing and a bad U joint. I think previous owner driving with bad U joint probably caused all the problems. Did those first, then the wheel bearing. I personally doubt that spindle could be the problem, but check the fit and condition of the spindle and spline. I think that play in a wheel bearing could be bench checked with a power bar or some other method. I checked my old (bad) bearing off the car and no movement can be felt by hand, only with wheel loading in place. Hope this helps! :D