Hi. I'm new to the forum. Just purchased a '01 SSEi last month. Does anyone know if there is somekind of backpressure valve on the '01 caliper piston that would not let the piston go back in. I was trying to replace my rear pads today and didn't want to force the pistion. I was using a regular sissor-type piston compressor. It didn't want to move at all.

I assume you took the cap off the brake reservoir? If all the other calipers compressed together fine then that one is siezed.

Yes, the cap was off. I didn't check any others after that one. I'll have to try taping around the edges of the piston to free it up. Just wanted to ask to make sure pontiac didn't have some new valve or device that kept it out.
Thanks.

No offense intended:

You do know that the rear pistons typically don't just push in like the fronts, right? Because they are also your park brakes, they turn in.

Now, mind you, I haven't actually change the rear pads on my bonne yet, but on dozens of other GM cars that I have done with rear calipers, you should use the tool that allows you to twist them in. Is the face of the piston flat, with two groove in it? If so, this is the twist in type. (I wish I could remember from when I pulled mine apart to paint the calipers)

(If you did know this, but still having problems, again no offense intended. )

Good luck.

The 2000+ Bonnevilles don't have the separate parking brake machanism like the Grand Prixs?? The GPs have an integated small drum with shoes in the rear rotors, otherwise the caliper mounting setup is the same as the front, just smaller.

Cheers,

(Lazy Freddi rememeber that he HAS manuals for the 2000, so goes to garage to get clarity)

Nope. Brake cable goes right to caliper, and the 2000+ does require a spanner wrench to retract the piston, as I suspected above.

Thanks for the replies.
I saw the EB cable on the caliper and notice no sm drum. There are v-notches on the piston but also pins on the pads to fit in them. I didn't notice a ring on the piston to tell me anyting would have been turning.
Do the large auto-chain stores carry this tool or is it a GM tool?
Looks like I need a manual on this pontiac. Any good suggestions.
Mince

Rear Brakes:
Remove two-thirds of the brake fluid from the master cylinder.
Raise the vehicle and suitably support.
Remove the tire and wheel assembly.
Important
Do not use a screwdriver or pry bar to compress the caliper piston into the caliper. Any damage to the piston boot could cause corrosive elements to enter the piston sealing area and lead to the piston seizing in the caliper bore.
Important
Do not exceed more than 1 mm of piston travel. Damage to the internal adjusting mechanism may result.

Using a large C clamp compress the caliper piston into the caliper bore to gain enough clearance to allow the caliper to pivot off the caliper bracket. Compress the piston until resistance is felt, but no more than 1 mm of piston travel.
Remove the park brake cable bracket from the brake caliper.
Remove the park brake bracket from the brake caliper. Leave the park brake cable attached to the cable bracket.
Disconnect the park brake cable from the brake caliper.
Remove the bottom caliper slide pin.
Pivot the caliper body upward.
Remove the inboard and outboard pads from the anchor bracket.
Remove and inspect the pad retainers.
Retract the caliper piston into the caliper bore. Use a spanner type wrench to turn the piston clockwise until it bottoms out fully in the caliper.
Align the cutouts in the caliper piston to the alignment pins on the back of the brake pads.
Reassemble. Tighten the caliper slide pin to 63 lb ft.

Thanks for all your help.