Never heard of a WC87504 coming in matched sets. Normally only "super" precision angular contact bearings come in matched sets for DB or DU mounting. More common on milling machines due to higher speeds and loads. A WC87504 is a "standard" bearing and would only come individually. If they are telling you they should be a "DB" mounting, you either have an OEM special that they've made, or the WC87504 was put there erroneously and it fails often.
That bearing is a 20x47x5/8" wide. Same ID and OD as a 6204, you may be able to sub a 6204 2rs sealed, but it a bit narrower???
Hope that helps...

 

I'll Pm you so as not to run on in this thread.
Thanks

 

Got the goo.. They squeak about 1000 times worse now. I have verified 100% that this problem of the light constant squeak, squeak is the brakes. With the caliper off the rotor spins free and easy with no noise.

Put the caliper back on and its squeaky time. I think maybe the next step is to replace the caliper. I noticed that the pads are pretty snug up against the rotor. I can push the pistons back into place by hand and they seem to relax back out and rest pretty firm on the rotor IMO.

Also, braking and coming to a stop on that left side tends to take the steering wheel to left, and there is a clunk that sounds like the brake releasing from the rotor or breaking free when I let off the brakes and begin to accelerate.

At this point, the squeaking is making the car completely undesirable to drive in.

 

Think maybe you got some of that "goo" on the rotors?

 

Nope.. not even a remote possibility... The darn thing just squeaks. All the goo was on the back of the pads. I think the caliper is bad.

 

Everything was fine until you re-packed the bearing.

It doesn't make sense to me that the caliper would fail just because you re-packed the bearing. Grease on the pad or rotor however will squeal like a pig.

 

No, it was not. The squeak has always been there.

(you have to read the thread from the beginning..)

I did not re-pack the bearings. I completely replaced them. There is no grease on the rotor, nor was there ever, and it does not squeal like a pig, it goes

squeak squeak squeak squeak squeak squeak

upon tire rotation

Just to reiterate the motivation for replacing the bearings was to

1) perform general maintenance on something that has not been touched in 30 years

2) attempt to eliminate existing 'squeak' 'squeak' noise

The squeak has always been there.

Later in this thread it was suggested that I should use the silicone goo on the back side of the pads where they butt up against the pistons. That is what I did...

Anyway, if you start at the beginning, its all there...

I think the caliper was just always bad. I had to replace the rear on the drivers side as well last year because it kept locking up.

 

The best method I've found to install new races is to spend 5 minutes taking one old race and w/ vice grips put it on a belt sander and sand down the outside diameter all the way around.
Then I use the old one on top of the new and pound the new one in, it puts equal pressure all around the new race and goes in great, no worry about damaging the new race.

 

Okay, this is going to sound really stupid, but its worth a shot. When I rebuilt my front suspension, I tested the smoothness of the bearings after installation. Well, it was squeeking for some reason, and mostly everything was new, so it was definitely not the brake caliper or rotor. I pulled the dust cap off the hub, and saw wear marks on the inside of the cup. The cotter pin was just barely touching the inside of the cup, and causing a squeaking noise. Its gone now.

 

I have also seen this before; good spot to check.

I do not think you have a caliper problem unless they leak.

What you are experiencing is the common C2, C3 break squeals. This is (as mentioned) a high frequency vibration that has nothing to do with bearings, or surface condition of the rotor/pads. This has existed since the cars were new.

It does have to do with the floating four piston design and rotor run-out. The pistons are supposed to have a load behind the pad keeping them to the rotor. The squeal is mostly corrected by the trueness and run-out of the rotor. All that it take to cause the squeal is just a little rotor warp.

If the spin is square then the problem goes away.

I have never heard of placing goo on the back of the pad and letting it dry before install. I have heard of using the teflon pad backings that many of the vendors sell.

I have also placed anti-squeal goo on the back of the pad and placed them wet just as conventional breaks bonding them to the pistons. Placing the pads without making a mess is doable just not easy. This, 99.9% of the time, corrects the squeal.

BTW, I have never seen the .1% fail of this method, however there is always a first if something is a contributor.

 

Buy a bearing installer kit, it does the same thing without all of the work.

 

Maybe I misunderstood this? (anyway, after doing so...)

At any rate just offering information on what I have seen in the past. Good luck.

 

The last time I replaced the front calipers - leaking due to extended storage, the tech who knows Corvettes told me to file the leading and training edges of the friction material at a 45° angle. That is, take the sharp 90° edge off to avoid any noise problems. You might try this with a coarse file before buying more stuff to fix the problem. It is surely the pads and not the caliper causing the noise.

The pull problem could be a caliper problem. I didn't read your entire post before replying. The 45° idea is still valid though.

Cheers,
Pete

 

I'm betting you have semi-metallic pads. Change to organic pads and the noise will disappear.

 

I was thinking along the same lines. It's likely not the caliper that's at fault here. Metallic pads or not, change them and file the leading and trailing edges as previously indicated. This will likely eliminate the squeak issue.

Good Luck!

 

Update...

Ok, pulled the wheel off, checked my bearings again that I had previously replaced, they are perfect... Pulled the pads as someone suggested and beveled the edges 45 degrees. Re-installed.

Still squeaks...

I give up. I'm gonna take it to my mechanic and replace all the brakes, rotors, calipers, lines, everything.. This is getting to be an exercise in futility.

The noise makes driving the car unbearable. Tried looking for organic pads btw, and no one has them... Well NAPA said they can get them, but it would be a few days... I am not confident that replacing the pads is gonna fix this. These ancient brakes are just crap.

Thanks for the help and advice..

 

Gee, they work pretty well for me.....

 

Last week I bought a set of AC Delco front wheel bearings from Dr. Rebuild. Little bit pricey.

Also, in case anyone knows, I have a question....I have a set of NOS front hubs (with the riveted rotor). The inner front wheel bearings races are installed in the hubs. Even though they've never been used, I will push the existing races out and install the races from the new bearing sets. Why would GM sell the hub with the inner race installed? Shouldn't the races be specific to a cone set? Are the dimensions controlled so much that GM NOS bearing sets had interchangeable cones and races?

 

The bearings are sold separately and there's no need to replace new races or to buy NOS bearings. USA Timkens are all you need.

Replacing the entire brake system for brake squeel is only going to waste your money. If your mechanic is honest he won't even attempt to do that. If you need organic pads call Muskegon Brake. If the calipers are not leaking, the hoses are good and rotors dialed in (under 003) get some 100 grit pads on a d/a and clean the rotors then try the pads. Be sure the pad pins are not worn as well.

 

Replacing/servicing the rear wheel bearings in my jaguar xjs is easier than this car. I guess this is probably one of therreasons why the general went to the sealed unit hub/braring assembly.