Question for the automotive gurus

[FHKracingZ]

I have a 2003 Chevy Express 3500 van. I recently had both front wheel bearing packs change, new rotors, and new pads installed. Every now and then when you apply the brakes it will start shaking so bad you will think the van is going to fall apart. The pitman arm is not loose, and the rotors were spun when they were installed. I was wondering if you think its maybe a steering gear? Or what would cause this. thanks!

[extremeblastr]

only thing that makes sense to me is the rotors being warped...other than can't really tell you.

[FHKracingZ]

Its not the rotors. The rotors were spun when they were put on and maybe have 2,000 miles on them. Rotors would do it every time you hit the brake also. This dosnt do it all the time.

[Tommy Warren]

you might want to try changing to ceramic pads they create less heat and with a big van it doesn't take long to heat up your front pads.

[extremeblastr]

Originally posted by FHKracingZ
Its not the rotors. The rotors were spun when they were put on and maybe have 2,000 miles on them. Rotors would do it every time you hit the brake also. This dosnt do it all the time.

does it only do it when your on the brakes hard? miles don't really matter you could end up with a warped rotor any time but i'll trust they're good. be a little more specific about when exactly it happens because something else has to be happening at the same time like it pulling to one side or something.

[FHKracingZ]

No pulling to either side. It just starts shaking horrible. The wheel will shake horrible. I mean it feels like the van is going to just break into 100 pieces. its very bad.

[Lowcountrydave]

Can you safely jack it up on jack stands. Inspect the work done.

Pull the tires off and see if you can shift the rotors, check for play. They might have not been tightened properly.

Make sure the castle nut and cotter key are in place, or if the nut has been staked, which ever you might have on your van.

Make sure the caliper bolts are in and tight. Check the brake pads, might be defective and come loose from the backing plate.

Caliper sticking? They may have rotated the caliper and reinstalled it with a kink in the brake line. It could collapse the line and cause issues.

Just a few things I could think of.

Dave

[BakerRacing40]

not sure how much this info will help or not but... my 07 (classic) pick up has a pretty good shake when you brake but as you said its only part of the time... and under different conditions, hardly ever the same..
i haven't dug into mine yet but probably will here shortly...