wstrohm

rxhead,

Did you experience the "screeching" only at full right or left steering lock, like I do? There is no noise when going straight on our FD. I am thinking I need new hub/bearing assemblies, since this occurs only when driving. When turning a corner, side stress is put on the bearings, but on the jack no such stress exists when spinning the wheels, and there's no noise in the latter case. Our car has 98,500 miles on its bearings... maybe they are just worn out.

Mahjik

iTrader: (1)

Have you done the break-in process of the pads/rotors yet?

wstrohm

mahjik,

We tried to find a place where we could do that, but we live in So. CA suburbia, and there are just no low-traffic roads around here for zipping up to speed & back down 10 times in a row. We did about 4 tries to 40 and down to 10, but ran out of road! The rotors are starting to shine up, there is no squealing when the brakes are used, also no noise in straight-ahead driving. The brakes themselves are working fine.

Mahjik

iTrader: (1)

Use a mall or shopping area after hours. It's possible that you just have the pad dragging a bit (which can happen with new pads). Is it a screeching or scrubbing? You mentioned both, but to me those are two different types of sounds.

IIRC, the package comes with Hawks? If so, some of that is unfortunately normal with those pads.

rxhead

The "noise" scrubbing was always there while driving... maybe a good 15 miles worth, can't remember if it was worse when turning though, sorry. The second set they sent me was the same. It may very well be your hub assembly but if the scrubbing/screeching started AFTER putting the new brakes on, my bet would be that one of the components is faulty. I would slap on your old rotors and take the car for a spin. Also check the lines and make sure they're secure.

dgeesaman

iTrader: (7)

Just a thought - I would turn the steering wheel to full lock where it rubs and see if you can find where it's rubbing. It might help to lift the front of the car and then put the jack under the tire to lift it and put that suspension under load. If the wheel is rubbing the fender liners you'll know it.

Dave

BillM

iTrader: (4)

You said you had to cut out a piece of the wheel liner, do you have larger wheels/tires? Make sure the liner is not sticking down anywhere and is pushed all the way in.

You replaced the brake line hoses with ss? Did you route them properly, check that.

If the hub or disk are out of round you most likely would feel that even when going straight so I dont think its that.

Put some chaulk on the tire and steer full left/right lock and then look under the fender to see where it rubs off.

wstrohm

Mahjik, indeed they are different; I was responding in kind to rxhead's post. The sound is a low, rough "scrubbing" or maybe "grinding" sound. I would think that pads dragging would occur no matter the position of the wheels, since they move with the wheels.Dave, I did that (see my post #24). Now that I have cut away the projecting edge of the plastic shield, even with the car on its wheels at either full lock, I can drag a folded terrycloth towel (about 4 thicknesses) over the top and down the front of the tire, and it makes no mark in the dust of the plastic shield, so there is (now) a lot of clearance. BillM, my wheels are the original OEMs, and my tires are Bridgestone Turanza LS-V 225/50R16, which is the stock size. I have checked the routing of the new brake lines and they touch nothing over their whole range of motion. The tires are no longer touching the fenderwell shield anywhere whether jacked up or on the ground. The noise is worse after re-jacking the car, cutting the plastic back, and driving again. Which is why I am ordering new hubs. If they don't solve the problem, I'm out of ideas. With 98,500 miles on the bearings, they probably need replacing just on general principles.

I appreciate the time you folks have taken to reply to this thread... you have all been helpful.

gracer7-rx7

iTrader: (16)

Did you use or re-use the factory brake clips on the pads?

Oddly enough, I recently discovered what might be a similar problem. My rear brakes squeal when I turn the front wheels close to full lock. It seems like the rear brakes rub slightly when the front wheels were turned. I only noticed this on track pads since they squeal loudly. No idea when or how this came about...

wstrohm

Yes, I did. "M" springs and clips on the front, "V" spring on the rear. The PBR pads came with integral shims bonded to the pad rears, but I added the existing used shims back in anyway, after greasing them per the manual.

BTW, there is no squealing, scrubbing, or grinding noise at all from the rear of the car.

(Also BTW, I just ordered the hub etc. parts from Ray Crowe.)

wstrohm

Received the hub assemblies today. The bearings are pre-greased, but with an almost clear, waxy grease. I have cans of Sta-Lube High-Temperature Disc Brake Bearing Grease, with which I would like to pack the hubcaps. But the Sta-Lube can says not to mix greases of "different base types." The Sta-Lube grease is an "aluminum complex base" but I have no idea whether it is compatible with the unknown Mazda grease. The Sta-Lube grease is also mixed with molybdenum disulfide, making it black.

Does anyone know what Mazda's grease "base" is?

dgeesaman

iTrader: (7)

I would leave it alone.

Dave

wstrohm

Dave, you mean go with the existing grease and don't fill the inside of the hubcap, right? This is because you think the greases would not be compatible? That leaves just air in the external volume between the outside bearing and the interior surface of the hubcap. Is this OK in the long term?

dgeesaman

iTrader: (7)

Yep, don't add any grease. Extra grease can cause problems (sealed-for-life bearings are usually only 25% full of grease inside) because of churning losses and excess heat. Then there is the mixture question too.

Dave

GoodfellaFD3S

iTrader: (213)

Are you still experiencing the noise when at full lock? I would also check your heat shields that are behind the rotors and make sure there isn't any interference with those.

wstrohm

I didn't add any grease. I have replaced both hub assemblies; the only holdup is that I screwed up the slots in one of the two Philips screws that hold the right front rotor in place. Had to drill out the screw. Will get a new one tomorrow if available. Hub nuts are torqued to about 140 lb-ft. The first hubcap was a real problem to put on, but I learned, and the 2nd one was easy. Calipers are remounted; no problems. Will try to finish tomorrow and drive the car... easy, if our Mazda dealer has that screw... P/N 99831-0616.

The dust shields have not been distorted. But I would expect any noise from them to occur at all steering angles anyway, since they are rigidly mounted to the movable portion of the suspension/wheel assembly.

dgeesaman

iTrader: (7)

You can omit the screw and put it together until the screw arrives. That screw only serves to keep the rotor from falling off when you pull the wheel.

Dave

wstrohm

Found a replacement screw ($0.60), bought 6ea with Allen heads. Job is complete. No more noise when turning 90° right or left, but still a slight scrubbing on U-turns at full lock. Wife considers car now driveable. Still don't know where the noise is coming from, but it's there at either right or left lock. It sounds inexpensive, no matter what it is, but I will be amazed if it's the tire hitting anything. (It sure sounds like tire against the plastic shield, though...)

Oh, well, the car now has new front bearings, 4 new rotors, new front & rear pads, S/S brake lines, and 4 overhauled calipers (hydraulics). But NOW wife says the brakes are once again slightly spongy. More air in the lines, I guess...

dgeesaman

iTrader: (7)

Borrow a power bleeder. They rock.

Or gravity bleed.