Brake pad replacement....

I recently had the rotors turned and replaced the front brake pads on my 1999 Silverado 1500 4x4.
Now when I apply the brakes , there is pulsing from left to right and a "knocking' sound. It sounds like the ABS is trying(or is) activating.
No problem before this service . Only wanted to take the "junk" out of the pedal and steering. Have found this is a good thing to do on any GM around 40k miles.
HELP!!!! This is driving me nuts.....I can't take this thing apart many more times!!!!!:lol:

AHHH!!!! I'm glad someone else is having the same problem. The EXACT same thing is happening to me. I just turned the rotors on my 99 silverado and the thing was workin just peachy for 1 day. After that, I started getting that knocking sound in the front drivers side. I pulled the fuse to the ABS and drove around and it still makes the sound which leads me to beleive its not the ABS. The rotors were just turned, so its not those. I've narrowed it down to something in the caliper. The guy at Napa Auto Parts suggested that its probably something wrong in the hardware of the caliper. Loose clips or something of that nature. Anyway, i'm getting new calipers to put on this evening. I'll let you know my results.

Why don't you just take it to the dealer or mechanic? It makes much more sense than trying to guess and figure it out yourself.

Actually, I took the truck to the dealer. They said that they dont fix problems, they replace them. They were gunna charge me $1k for labor and parts to replace all rotors and calipers. I am filthy rich, single, and handsome, but the dealer already has enough of my money.

Make sure the caliper is on good and tight. If it is loose it will move around and feel that way.

Allright, well i was fed up with this clunking sound when i was braking an i knew it wasnt the rotors cuz i just had those turned. It was part of the caliper but i'm still not sure which part. I went to the parts store and bought two new calipers and some new ceramic brake pads. Took the old stuff off and put the new stuff on. To make a long story short, its all better. New calipers were round $50 a peice with trade in and brake pads were about $50 as well for the whole front end. Even after taking all the old stuff apart, i still cant figure out what was making that noise.
Some things to keep in mind. Make sure ya have a buddy to help ya bleed your brakes. You'll need a special tool to get the caliper mounting bolts out. Make sure ya have plenty of brake fluid on hand. Make sure ya greese up the caliper mounting bolts before ya put them back in. Its kind of a pain in the butt however you'll save a buncha money rather than taking it in to the dealer.

Ok, so i replaced the calipers. Clunking sound gone, however the truck is still doing a bunch of bumpy braking. Talked to my neighbor. He said his dad had the exact same problem after he had his rotors turned. He said something about the metal getting softer or warping easier after they've been turned so he bought two new rotors and problem solved. I suppose i oughta do the same.

Yeah if they're turned and too much material is removed, the thinner metal will heat up faster and warp much easier than the stock thickness. Rotors are cheap, accidents because you couldn't stop quick enough aren't.

It's also important to torque the lugs down to specs after putting wheels back on. If the torque on the lugs isn't equal, it can actually contribute to warping the rotors.