Front End Noise - Wheel Bearing?

[Larry T.]

I have a noise I would best descridbe as a "clu, clu, clu" noise in the front end. It begins at extremely low speed (rolling down the driveway) and continues until the road noise blocks it out. It does speed up as the travel speed increases. I have isolated it near the front right wheel. It only makes the noise when moving forward and it softens when I turn right and goes away when I turn left.

I pulled the wheel off and removed the outer bearing and hub. The spindle nut was torqued to 12 ft. lb. and nothing seemed particularly loose, although there is a little play in the outer bearing. I do not know what is normal. The bearings seem to turn smoothly enough by hand. The outer race looked okay as does the spindle. I am already this far so I can easily replace the bearings and races, but is their any other culprit I should be looking at? Is it possible they just need to be re-packed? If I replace should I consider doing both sides?

It seems straight forward enough, but I want to double check myself.

Thanks.

[Michael W.]

Re: Front End Noise - Wheel Bearing?

The spindle nut was torqued to 12 ft. lb. and nothing seemed particularly loose, although there is a little play in the outer bearing.

12 ft/lbs? I hope you're not driving the car like that! That torque level is only to initially seat the bearing, not the final setting. The nut must be backed off from that as per GM shop procedures.

The noise you're hearing might simply be brake pads skimming the rotor surface.

[Joe L.]

Re: Front End Noise - Wheel Bearing?

I have a noise I would best descridbe as a "clu, clu, clu" noise in the front end. It begins at extremely low speed (rolling down the driveway) and continues until the road noise blocks it out. It does speed up as the travel speed increases. I have isolated it near the front right wheel. It only makes the noise when moving forward and it softens when I turn right and goes away when I turn left.

I pulled the wheel off and removed the outer bearing and hub. The spindle nut was torqued to 12 ft. lb. and nothing seemed particularly loose, although there is a little play in the outer bearing. I do not know what is normal. The bearings seem to turn smoothly enough by hand. The outer race looked okay as does the spindle. I am already this far so I can easily replace the bearings and races, but is their any other culprit I should be looking at? Is it possible they just need to be re-packed? If I replace should I consider doing both sides?

It seems straight forward enough, but I want to double check myself.

Thanks.

Larry------


The front spindle nut should not be torqued to 12 lb/ft in service. It should be torqued to 12 lb/ft and then backed-off one flat. This results in zero pre-load on the bearing and an end-play in the range of 0.001- 0.006. If the nut was torqued to 12 lb/ft and left there, that would result in a significant pre-load on the bearing and zero end-play.

The above may or may not be the cause of your problem, however. It's very hard to say what's causing the noise you describe. It might just be slight movement of the brake pads in the caliper. It might be trim ring caused noise (remove the trim rings and see if the noise persists). It might be other things or it might be that the noise isn't really originating at the front, at all.

As long as you have the front bearings out and considering the 12 lb/ft torque you apparently found the nuts torqued to, I would replace both front bearings with high quality new bearings. These don't really cost all that much and, if the ones you have in there are original to the car, you won't be wasting much money if you replace them. By the way, if the bearings are stamped "NDH" or "New Departure-Hyatt", the chances are they are original to the car.

[Richard T.]

Re: Front End Noise - Wheel Bearing?

If your car has disk brakes it could be one of your brake pad ware indicators rubbing against the rotor, which will require pad replacement; do both wheels if this service is needed. Bearing's make a growl noise when they are worn out and a lot of play in the wheel will indicate trouble, top to bottom in and out test will reveal this defect. Any metal filings in the grease or the hub cavity is a sign of ware and the need to replace the bearings. Use U.S.A. built bearing and seals if you decide to replace them. Good Luck.

[Paul J.]

Re: Front End Noise - Wheel Bearing?

Larry,

You said that the bearings look OK, no discoloration or signs of heat? Then I think it's the brake pads.

However, since you're into it this far you might as well replace the bearings, as Joe suggested.

Paul

[Joe L.]

Re: Front End Noise - Wheel Bearing?

If your car has disk brakes it could be one of your brake pad ware indicators rubbing against the rotor, which will require pad replacement; do both wheels if this service is needed. Bearing's make a growl noise when they are worn out and a lot of play in the wheel will indicate trouble, top to bottom in and out test will reveal this defect. Any metal filings in the grease or the hub cavity is a sign of ware and the need to replace the bearings. Use U.S.A. built bearing and seals if you decide to replace them. Good Luck.

Richard------

I don't think that any 65-82 Corvette brake pads I've ever seen had the wear indicators that some later GM brake pads have. Of course, there might be some out there that do, but, if so, I've never encountered them.

[John H.]

Re: Front End Noise - Wheel Bearing?

If your car has disk brakes it could be one of your brake pad ware indicators rubbing against the rotor, which will require pad replacement;

Richard -

Corvette 4-piston disc brakes don't have pad wear indicators.

[Dick W.]

Re: Front End Noise - Wheel Bearing?

Thoroughly wash all the old grease out of your bearings. Inspect the bearing cups and the inside of the race. You can do this by holding it up to a bright light and looking between the rollers. Look for pitting, as that could give you the sound you are talking about. Look at the large end of the rollers, there should be an indentation in the center. If the bearing were over torqued for a long perior of time, the end could be worn down to the point that the indentation is gone. DO NOT spin the bearings with high pressure air.

If the bearings appear to be OK, lightly oil them before packing them with a quality disc brake wheel bearing grease of your choice.

[Larry T.]

Re: Front End Noise - Wheel Bearing?

Larry------


The front spindle nut should not be torqued to 12 lb/ft in service. It should be torqued to 12 lb/ft and then backed-off one flat. This results in zero pre-load on the bearing and an end-play in the range of 0.001- 0.006. If the nut was torqued to 12 lb/ft and left there, that would result in a significant pre-load on the bearing and zero end-play.

Joe,

The way you describe it is how it was. I put the torque wrench on tightened it a fraction of a turn and the wrench popped pretty quickly. If I backed it up one flat it would be right back where it started.

Thanks.

Larry

[Larry T.]

Re: Front End Noise - Wheel Bearing?

Larry,

You said that the bearings look OK, no discoloration or signs of heat? Then I think it's the brake pads.

However, since you're into it this far you might as well replace the bearings, as Joe suggested.

Paul

The brake pads look good and there discoloration of the outer bearing (I did not remove the inne yet). But under a 10x loupe ther is some pitting noticible. Also, the bearing is marked Made in China. I will just plan to replace both sets. One thing I am reminded of, when I applied the brakes the noise also subsided. Could the brake shoes be rocking back and forth? If so, how can that be stopped?

Thanks.

[Joe L.]

Re: Front End Noise - Wheel Bearing?

The brake pads look good and there discoloration of the outer bearing (I did not remove the inne yet). But under a 10x loupe ther is some pitting noticible. Also, the bearing is marked Made in China. I will just plan to replace both sets. One thing I am reminded of, when I applied the brakes the noise also subsided. Could the brake shoes be rocking back and forth? If so, how can that be stopped?

Thanks.

Larry-----


The brake pads normally "rock" slightly when direction is reversed but should not at other times.

However, you might want to check to see if the front rotors have excessive runout on them. If this occurs, it causes the brake pads to move slightly "in-and-out" as the rotor goes through a revolution, causing the backing plate ends to rub on the caliper. This usually causes a squeaking sound. It will stop immediately upon application of the brakes since that action "immobilizes" the pads.

If runout is the problem on the front, then the rotors need to be machined with the hubs on a brake lathe to correct it. TIR should not exceed 0.005" and less is better.

When installing new bearing outer races, make sure that they are completely seated in the hubs.

[Michael W.]

Re: Front End Noise - Wheel Bearing?

Could the brake shoes be rocking back and forth? If so, how can that be stopped?

Thanks.

If the runout is acceptable, then possibly the noise is caused by lack of lubrication at the contact point of the retaining pin and pads. A tiny spot of grease is all that's required.

[Ricky M.]

Re: Front End Noise - Wheel Bearing?

On the '63 roadster I bought in May I had the exact same symptoms. I had 2 different people ride with me and we all isolated it to the front right whee(at a slow roll till you couldn't hear it anymore). As I drove more it got louder(still right front wheel) Put it on the rack to look around and all seemed ok. While it was up I decided to change halfshaft joints since it looked as if they hadn't been changed lately. That solved the problem. I don't know if if was noise transference or what. 1000 + miles later and all is good. I would have never believed that if I hadn't done it myself, that dogone noise was in the right front. FWIW

[Joe L.]

Re: Front End Noise - Wheel Bearing?

On the '63 roadster I bought in May I had the exact same symptoms. I had 2 different people ride with me and we all isolated it to the front right whee(at a slow roll till you couldn't hear it anymore). As I drove more it got louder(still right front wheel) Put it on the rack to look around and all seemed ok. While it was up I decided to change halfshaft joints since it looked as if they hadn't been changed lately. That solved the problem. I don't know if if was noise transference or what. 1000 + miles later and all is good. I would have never believed that if I hadn't done it myself, that dogone noise was in the right front. FWIW

Ricky-----


I agree. In fact, that's why I mentioned in my first post the possibility that the noise might not be originating in the front, at all. The kind of noise that's been described is very often caused by half shaft u-joints. If the joints have served for 50,000 miles, or even less in many cases, they could be shot. People are often absolutely amazed when they replace these joints to see just how bad they can get while demonstrating very little symptoms.

The fact of the matter is this: 1963-82 Corvette front wheel bearings rarely give problems and are extremely long-lived if they receive even occasional repack. However, 1963-82 Corvette REAR wheel bearings and half shaft u-joints are a VERY common source of problems.