My New Front Brakes and Wheel Bearings

[ConchZ]

Thought I'd pass along my brake and bearing story, hoping it helps someone else out. I had two different problems I was trying to solve. First, I had a front end shimmy that I could feel in the wheel, especially at highway speeds when going around a curve. Second, I had pulsating in the brake pedal when applying the brakes that was an obvious rotor problem. I also had recently developed a random pull to the left or right when applying the brakes. I had already balanced the wheels and replaced the springs, struts and bushings, which really helped the shimmy, but didn't cure it. I attributed the random pull to my calipers being 25 years old, according to how they looked, and the receipts in the box from the previous owner. The calipers also randomly stuck in their active position, dragging on the rotor slightly. It was also nearly impossible to bleed them, as their bleeder screws were rusted up.

Despite it being 25 years since the calipers were replaced, they only had about 20,000 miles on them. I hated to replace them, but I guess their internals had rusted and what not. So, I ordered new rotors, pads and calipers from R1 Concepts, and wheel bearings from Oreily, since I had no idea when the bearings were last replaced.

I followed this link from Atlantic Z for replacing the bearings, and basically used what little brains and experience I had to finish out the how-to on the brakes, since those are easy. To drive my bearing races, I wussed out and bought this set from Harbor Freightfor $25, instead of making my own.

I've never done the bearings before. Pretty easy, although there's a lot of little stuff that isn't in the tech tips. For example, when you first put the hub/rotor assembly back on the spindle, it won't just slide on the spindle nice and easy. You have to jimmy it around, and even tap it into place with a hammer to get it the last half inch. Once in place, if you don't immediatly put the outer bearing in, it's going to slide back off the spindle, leaving the inner bearing and seal on the spindle, making a huge mess of grease along the way. What a pain it was on the first side. I had to get brave enough to use the hammer, since I was worried that maybe there was something wrong with my assembly that was keeping it from sliding all the way onto the spindle. The second side when fast.

The loaded calipers went on quickly, as did the bleeding. Off the jack stands, and out to bed (brake pads, that is). Following directions from R1, I heated up the brakes, without ever coming to a complete stop, and if I had to stop, I used the emergency brake for the last little bit of stop, so the front pads wouldn't sit on a hot rotor. I got those pads and rotors so hot that I started to lose stopping power, and the brake light even lit up on the dash. Probably over did it.

The next day, after the brakes had cooled, I began enjoying absolutely smooth running, with no vibrations or pedal pulse. It's like a whole new car. Well, its still loud and a bit stinky(got a leaky fuel vent hose), but it is noticably smoother and stops straight and predictably.

Here's some pictures. Notice that my old rotors had two circles cut into them. What are those about? The circles are on both sides of both rotors, and were so perfect that I think they were there on purpose and not a result of pads wearing out and the backing plate cutting the rotor. I'm speculating they were done to decrease brake dust. Anyone else seen this?

Edited June 10, 2010 by ConchZ

[ConchZ]

The pics are self explanatory. Don't know why they wouldn't attach the first time. Enjoy.

[Pomorza]

Thought I'd pass along my brake and bearing story, hoping it helps someone else out. I had two different problems I was trying to solve. First, I had a front end shimmy that I could feel in the wheel, especially at highway speeds when going around a curve. Second, I had pulsating in the brake pedal when applying the brakes that was an obvious rotor problem. I also had recently developed a random pull to the left or right when applying the brakes. I had already balanced the wheels and replaced the springs, struts and bushings, which really helped the shimmy, but didn't cure it. I attributed the random pull to my calipers being 25 years old, according to how they looked, and the receipts in the box from the previous owner. The calipers also randomly stuck in their active position, dragging on the rotor slightly. It was also nearly impossible to bleed them, as their bleeder screws were rusted up.

Despite it being 25 years since the calipers were replaced, they only had about 20,000 miles on them. I hated to replace them, but I guess their internals had rusted and what not. So, I ordered new rotors, pads and calipers from R1 Concepts, and wheel bearings from Oreily, since I had no idea when the bearings were last replaced.

I followed this link from Atlantic Z for replacing the bearings, and basically used what little brains and experience I had to finish out the how-to on the brakes, since those are easy.

I've never done the bearings before. Pretty easy, although there's a lot of little stuff that isn't in the tech tips. For example, when you first put the hub/rotor assembly back on the spindle, it won't just slide on the spindle nice and easy. You have to jimmy it around, and even tap it into place with a hammer to get it the last half inch. Once in place, if you don't immediatly put the outer bearing in, it's going to slide back off the spindle, leaving the inner bearing and seal on the spindle, making a huge mess of grease along the way. What a pain it was on the first side. I had to get brave enough to use the hammer, since I was worried that maybe there was something wrong with my assembly that was keeping it from sliding all the way onto the spindle. The second side when fast.

The loaded calipers went on quickly, as did the bleeding. Off the jack stands, and out to bed (brake pads, that is). Following directions from R1, I heated up the brakes, without ever coming to a complete stop, and if I had to stop, I used the emergency brake for the last little bit of stop, so the front pads wouldn't sit on a hot rotor. I got those pads and rotors so hot that I started to lose stopping power, and the brake light even lit up on the dash. Probably over did it.

The next day, after the brakes had cooled, I began enjoying absolutely smooth running, with no vibrations or pedal pulse. It's like a whole new car. Well, its still loud and a bit stinky(got a leaky fuel vent hose), but it is noticably smoother and stops straight and predictably.

Here's some pictures. Notice that my old rotors had two circles cut into them. What are those about? The circles are on both sides of both rotors, and were so perfect that I think they were there on purpose and not a result of pads wearing out and the backing plate cutting the rotor. I'm speculating they were done to decrease brake dust. Anyone else seen this?

Two things.

1. I see no photos. I think you forgot to insert them or something.

2. When you mean bed the pads what exactly does that mean. I just did the same thing you did (calipers pads and rotors) and when I was done I just took it for a nice long drive and applied the brakes a bit harder. Did I miss something?

Jan

ooops didn't see your second post until after...sorry.

And one more thing. Are the pads supposed to ride on the rotor a bit. Mine do, just a tad so you can hear them when you drive.

Edited June 10, 2010 by Pomorza

[ConchZ]

I can't hear the pads riding on the rotor when driving, although with the wheels/tires off, I can hear just barely them as I spind the hub. I figured it all would work its way loose with time. If yours are riding all the time, and making it hard to spin the wheel/hub freely when on a jack stand(like my old ones were), you might need to spread the rotor with a spreader tool, and then put it back on. You can buy a spreader pretty cheap at any auto parts store. It'll push the pistons back into the caliper all the way. Not sure if that'll help, since the pistons will just push back out the first time you use them, but it might. If your rotors are really sticking, I'm guessing they need replacing. Mine started out that way, then began doing the random grabbing and pulling.

Bedding the pads involves heating them up enough to leave a thin, but even deposit of pad material on the rotor. This is thought to keep them from leaving one big deposit in one place the first time you get them really hot, then stop at a stop light with your foot on the brake for a while. This big deposit in one place is thought to be the cause of pedal pulsation upon braking, more so than actually warped rotors. You bed the pads by doing half a dozen near stops from 60 mph, one right after the other. Don't stop all the way, as that'll cause the problem you are trying to prevent. Not sure if bedding works, but it's free so I gave it a go.

Edited June 10, 2010 by ConchZ

[Pomorza]

I can't hear the pads riding on the rotor when driving, although with the wheels/tires off, I can hear just barely them as I spind the hub. I figured it all would work its way loose with time. If yours are riding all the time, and making it hard to spin the wheel/hub freely when on a jack stand(like my old ones were), you might need to spread the rotor with a spreader tool, and then put it back on. You can buy a spreader pretty cheap at any auto parts store. It'll push the pistons back into the caliper all the way. Not sure if that'll help, since the pistons will just push back out the first time you use them, but it might. If your rotors are really sticking, I'm guessing they need replacing. Mine started out that way, then began doing the random grabbing and pulling.

Bedding the pads involves heating them up enough to leave a thin, but even deposit of pad material on the rotor. This is thought to keep them from leaving one big deposit in one place the first time you get them really hot, then stop at a stop light with your foot on the brake for a while. This big deposit in one place is thought to be the cause of pedal pulsation upon braking, more so than actually warped rotors. You bed the pads by doing half a dozen near stops from 60 mph, one right after the other. Don't stop all the way, as that'll cause the problem you are trying to prevent. Not sure if bedding works, but it's free so I gave it a go.

Thanks for the help mate. The calipers I put on were brand new and the pistons were all the way in. I might take it to my mechanic and see what he says.

Jan