Brake Problem 07 Sierra ***All Hands On Deck***

[GeorgeG.]

hey guys, I need some suggestions here. I needed to tackle a couple of things on my truck. One of them was the brakes. The rear shoes were worn and out of adjustment and caused my front rotors to warp. I've done brake jobs for my vehicles for the past 20 years. I've never had an issue with replacing pads/shoes and rotors/drums.

So, I replaced the rear drums, shoes, front pads (Wagner OEx), and turned the rotors since they were replaced 2 years ago. Put it all together and I get this vibration when braking. Almost like warped rotors but faster shaking/pulsing. Kinda like a chatter without any noise.

First thought was that Oreilly's might have screwed up turning the rotors. It was late in the day so I didn't have time to take them back up there so I bought new rotors. Put it all back together and same thing as above.

Second thought was that maybe I over adjusted the rear shoes. Jack up the rear and loosen the shoes so there's very little drag when sliding the drums on. Put it all back together and same thing as above.

By this time I call it a night.

This morning I thought, I've never tried the Wagner OEx pads before. So I put the old pads back on (Wagner Thermoquiets). Go for test drive and the noiseless chatter is still there.

Then think, loosen the shoes some more. Lift up the rear wheels and loosen the shoes a lot, try it again and no luck.

What the hell is going on here? I have new drums/shoes (O'Reilly's Brake Best Select), new rotors (Brake Best Select), new pads (Wagner OEx). I can't even tell if it's coming from the front or rear.

Like I said, I've done this many, many times. I can do them in my sleep. When depressing the calipers, I opened the MC cap to allow the fluid to fill up. Then I take an old pad and slowly depress the pistons back in. Close the cap, slowly press the peddle so the pistons expand and done.

I'm not even sure what to check any more. I've had this thing in the air 4 times now! Which is a lot when using a jack and jack stands.

[GeorgeG.]

While googling... It's not the ABS kicking in. I've felt that before and it's not that.

[JC316]

Do the break in procedure and see if it stops.

http://www.wagnerbrake.com/tech-tips/break-in

[Captain Crawfish]

I have an 07 Silverado. I feel like a warped rotor cause it grabs and releases under braking. Been waiting for pads to start squeeking before I replace all of it. Which wheel did you replace first? Maybe they need to be bled in sequence although I'm sure you probably did that. Put a dial indicator on your new rotor and see if maybe you can see if one is off more than the other. Harbor freight has them cheap. It's not uncommon to get a pos rotor out of the box

[GeorgeG.]

I have an 07 Silverado. I feel like a warped rotor cause it grabs and releases under braking. Been waiting for pads to start squeeking before I replace all of it. Which wheel did you replace first? Maybe they need to be bled in sequence although I'm sure you probably did that. Put a dial indicator on your new rotor and see if maybe you can see if one is off more than the other. Harbor freight has them cheap. It's not uncommon to get a pos rotor out of the box

I didn't bleed the brakes. I just remove the master cylinder cap so the fluid goes back into the reservoir when pushing in the caliper pistons.

I did the break in...can't say it really got any better just yet.

However, there's a good chance the issue is due to my wheels being out of alignment rather than the brakes. The other thing I was doing today was going back through my strut replacement issue.
http://www.dfwmustangs.net/forums/sh...ighlight=strut

[LaserSVT]

Replace the rotors. Get Bosch Quiet Casts. Will need to replace the pads again as well. Also make sure you have a tiny bit of drag on the drums. If there isnt any you need to adjust them.
Usually when a GM wears out its rears it also blows a wheel cylinder. Couldnt hurt to pull back the boots and check for moisture.

[Cooter]

I've had rotors and drums be out of round right out of the box

[kingjason]

Is there a shim or a little tension spring on the pads you might have missed or did you lube the back of them so they wouldn't rattle? Sometimes as the calipers wear the pads don't fit as tight as they should and they will rattle.

[GeorgeG.]

I've had rotors and drums be out of round right out of the box

It occurred to me yesterday morning that I could isolate the brake issue to the front/rear by using the parking brake only to slow the truck down. So after doing that, it was definitely coming from the rear...same vibration.

Took the drums back to get mic'd and sure enough, one of them was a damn oval. It was way out of round, even the counter guy was surprised by how bad it was. This was definitely a first for me.

After another new set of drums and shoes and I am good to go! Thanks everyone for the suggestions.

[Captain Crawfish]

What was the final consensus on brand of rotors? Bosch?

[svauto-erotic855]

I've had rotors and drums be out of round right out of the box

This.

I measure run out on every rotor or drum before I put them into service. You can easily measure the drums run out if you flip the drum over and hand tighten a few of the lug nuts. If I have to tell you how to measure a rotors run out you do not need to be working on cars.

[svauto-erotic855]

What was the final consensus on brand of rotors? Bosch?

I have great luck with all of the major brands. Wagner and Raybestos are the two that I use the most.

[GeorgeG.]

What was the final consensus on brand of rotors? Bosch?

They're the Brake Best brand. That's what I've always used and never had an issue till now. I may consider the upgraded brands next time around.

[blackedv]

It also depends on how theyre stored on the shelfs at the store, its a pretty good bet that the drums were stored on their sides which ofcourse is a nono with drums.