ever loosening wheel bearings....

So, I installed my new wheel bearings a couple of weeks ago, and I noticed a vibration the other day. I found they were loose, but the collars were not (meaning they had not backed off).

So, I adjusted them again, using the process to tighten the collar mechanically while turning the rotor, back it off, and then finger tighten it. They seemed fine.

A few days later, and they were loose again..... Both sides....

What am I missing here?

Stan I have never been in there. Are they the tapered bearings with two cones.

If so, sometimes the cone/rases do not seat all the way and you really have to crank them tight to seat everything before you loosen them off and set to the correct preload. If they are new bearings they can be set tighter as they will ware.

Brad

Need more info Stan........which bearings? which 928?

Brad theres 2 sets of brgs per hub.

928mac;9007 wrote: Stan I have never been in there. Are they the tapered bearings with two cones.

If so, sometimes the cone/rases do not seat all the way and you really have to crank them tight to seat everything before you loosen them off and set to the correct preload. If they are new bearings they can be set tighter as they will ware.

Brad

malcolm;9008 wrote: Need more info Stan........which bearings? which 928?

Brad theres 2 sets of brgs per hub.

Front bearings, '90 GT.

If worst case scenario is that I need to keep adjusting them until I have them properly seated, I can live with that. It is a quick process to do, once it has been done a few times

I am always hesitant to over tighten things, I did it too often when I was a teenager and didn't yet have a torque wrench. In this case a torque wrench can not be used.

malcolm;9010 wrote: ok........did you take the hub off?

If not they might not be centered in the races.

BTW.......the vibration will wreck the bearings.....they should be set correctly before driving.

I took the hub off to replace the bearings of course. I also woosed out on punching the races out myself, and had a local shop do it, as they do such work all the time.

The rotors seem to spin just fine, making me think they are set right.

This problem is not much different than where I started, as the bearings needed adjustment, so I figured why not change them since the car has 165k on it. I was getting the vibration before changing them, and am now adjusting them as the vibration shows up.

malcolm;9024 wrote: Stan....I meant did you take the hub off and do both sets per side? Just wanted to be clear of course.

the proceedue per the WSM is very specific:

Yes, those are the directions I followed, the level of torque to be applied is subjective and I am probably more inclined to not torque too much.

Inner and outer wheel bearings and races were replaced on both sides of the front of my '90 GT. The actual bearing and race install, in the hub, was performed by a local service shop.