2002 GS Brake Question

What is the correct way to push the piston back into the brake caliper? I used a C-Clamp, which has always worked in the past on other cars, but later heard that I should have opened the bleeder screw.

Is there a one way valve on the front brake line?

I replaced the pads and rotors, but still have a warped rotor. The piston in the caliper might be stuck from dirt, or it might have pressure on it from the valve (if there is one).

BTW, I've searched this forum but couldn't find the answer to this question.


Thanks in advance.

I use a c-clamp but crack the bleeder valve slighty and then later bleed any possible air from the system. I don't recall whether there is a one way valve on each front brake line but there are proportioning valves and the biggest item between the calipers and the master cylinder is the ABS motor pack/modulator.

What brand or quality/grade rotors are you using?

The reason they recommend that you open bleeder screws, is not only the chance to introduce new fluid to the system, but also, over time, as the internal rubber components rot out, it leaves small amounts of debris in the braking system. When you compress the calipers, it forces that debris along with the fluid back through the system, and they dont want you to damage an ABS control unit by sludging it up. I've never had a problem leaving the bleeders alone.
As far as compressing, I've found the easiest way is to tap a beefy screwdriver inbetween the rotor and the inboard pad about 1/4 - 1/2 inch or so. Pry gently back on the screwdriver and push the pistion back using the old pad that you dont care about any longer. When its fully back in its bore, you can also insert it inbetween the outboard pad and caliper or rotor to make sure that your slide pins arent frozen. On HD GM pads, use it to bend those annoying spring clips back too.
If you use a c-clamp, make sure you leave the old inboard pad against the pistion to avoid cracking it--some manufacturers are using a plastic piston now.
Some brake hoses are known for deteriorating on the inside where they mount to the struts and create an unwanted 'check valve' that wont allow the QTU master cylinder to relieve the pressure. If this is suspect for sticking calipers, take a screwdriver and genly open this bracket just a little bit.

Some brake hoses are known for deteriorating on the inside where they mount to the struts and create an unwanted 'check valve' that wont allow the QTU master cylinder to relieve the pressure. If this is suspect for sticking calipers, take a screwdriver and genly open this bracket just a little bit.

Good basic info. I've never had problems with any of the brake hoses deteriorating on any of my "W" body cars causing a so called "check valve" effect but possibly worth checking into.

Note FYI: The brake line bracket is not mounted to the struts in a '97 - '04 Regal. Mounted on the inner part of the fenderwell.

In my experiences premature rotor warpage or excess lateral runout is caused by improper installation/work or poor quality rotors and pads. Also, improper torquing of the wheel nuts and incorrect value. 100 ft-lbs.

What brand or quality/grade rotors are you using?
The rotors are Brembo. I don't remember the name brand of the pads, but they are ceramic.

The rotors are Brembo. I don't remember the name brand of the pads, but they are ceramic.

Brembo? It figures. I'd like to say you have a nice name brand quality rotor but there are issues with Brembos. Specifically, rotor warpage around 6 months use. I've seen numerous complaints on Brembo replacement brake parts. Any warranty left?