Hi all...new member and my first post. This board looks like it'* right up my alley!

2005 GXP bought it new.
Did the front pads, rotors last night. Seemed fairly straight forward. Tore into the rears tonight and what am I missing here? There is 2 bolts for the pad bracket on the rear of the backing plate and only seems to be one bolt for the caliper sliders. The other is a cap with a little rubber boot. The fronts there were 4 bolts. 2 for the caliper/sliders and 2 for the pad bracket. It did not look like this "cap" on the rear top slider came off and I did not want to wreck anything trying to pry on it. So I set it down and came in to search. Did a quick search on here but nothing came up.

Can anyone help?

Thanks,
Kurt

ok...I did find one post about this on an Aurora:
http://www.bonnevilleclub.com/forum/...=rear+calipers

It said something about a tool for the rear calipers and that they TURN back in???
I just slowly pushed in the fronts with a C clamp and socket the way I have done it for 20 years. Even though they are duel piston it seemed to go just fine. Test drove it after doing the front and it was ok.
Was I not supposed to do this?
Whats the deal on the rear calipers?
That thread also said just to take off the one slider bolt and swivel the caliper and there would be enough room to change the pads. What about cleaning and re-greasing that other slider?

Yes, they do in fact screw back in. Most rear discs do this.

Removal Procedure
Inspect the fluid level in the brake master cylinder reservoir.
If the brake fluid level is midway between the maximum-full point and the minimum allowable level, no brake fluid needs to be removed from the reservoir before proceeding.
If the brake fluid level is higher than midway between the maximum-full point and the minimum allowable level, remove brake fluid to the midway point before proceeding.
Raise the vehicle and suitably support. Refer to Vehicle Lifting.
Remove the tire and wheel assembly. Notice: When using a large C-clamp to compress a caliper piston into a caliper bore of a caliper equipped with an integral park brake mechanism, do not exceed more than 1 mm (0.039 inch) of piston travel. Exceeding this amount of piston travel will cause damage to the internal adjusting mechanism and/or the integral park brake mechanism.
Using a large C clamp, compress the brake caliper piston into the brake caliper bore to gain enough clearance to allow the brake caliper to pivot off the brake caliper bracket. Compress the piston until resistance is felt, but no more than 1 mm (0.039 inch) of piston travel.
Remove the park brake cable guide bolt from the lower control arm.

Remove the bottom brake caliper pin bolt. Notice: Support the brake caliper with heavy mechanic'* wire, or equivalent, whenever it is separated from its mount and the hydraulic flexible brake hose is still connected. Failure to support the caliper in this manner will cause the flexible brake hose to bear the weight of the caliper, which may cause damage to the brake hose and in turn may cause a brake fluid leak.
Pivot the brake caliper body (6) upward and secure out of the way with heavy mechanic'* wire. Do NOT disconnect the hydraulic brake flexible hose from the caliper.
Remove the inboard (2) and outboard (3) brake pads from the brake caliper bracket (5).
Remove and inspect the brake pad retainers (1).

Installation Procedure


Inspect the brake caliper bolt suspension boots for cuts, tears, or deterioration. If damaged, replace the brake caliper, pin boots.
Inspect the brake caliper pin bolts for damage or corrosion. Replace if damaged or corroded. Do not attempt to clean away corrosion. Corrosion is typically caused by damaged pin boots.
Inspect the brake caliper piston boot for deterioration, repair or replace the brake caliper if damaged. Refer to Brake Caliper Replacement - Rear.
Retract the brake caliper piston (2) into the brake caliper bore. Use a spanner type wrench to turn the piston (2) clockwise until it bottoms in the brake caliper bore and align the piston.
Align the cutouts in the brake caliper piston to the alignment pins on the brake pads.

Apply a thin coat of high temperature silicone lube to the rear brake caliper bolts.
Install the brake pad retainers (1) into the brake caliper bracket (5).
Install the inboard (2) and outboard (3) brake pads into the brake caliper bracket.

Pivot the brake caliper down over the brake pads and into the brake caliper bracket. Notice: Refer to Fastener Notice in Service Precautions.
Insert the lower brake caliper pin bolt.
Tighten the brake caliper pin bolt to 27 Nm (20 ft. lbs.).
Install the park brake cable guide bolt to the lower control arm.
Tighten the park brake cable guide bolt to 24 Nm (18 ft. lbs.).
Install the tire and wheel assembly,
Lower the vehicle.
With the engine OFF, gradually apply the brake pedal to approximately 2/3 of its travel distance.
Slowly release the brake pedal.
Wait 15 seconds, then repeat steps 14-15 until a firm brake pedal is obtained. This will properly seat the brake caliper pistons and brake pads.
Fill the brake master cylinder reservoir to the proper level. Refer to Master Cylinder Reservoir Filling in Hydraulic Brakes.
Burnish the pads and rotors.

blubyu...thanks!
I laughed when I saw where your from. I live in Hampshire as well! Small world!

I take it this is out of the service manual? Looks like you work on it as an assembly and don't seperate the caliper from the pad bracket.
So that means no cleaning of the sliders and the one on top is fixed and not removable...hmmmm...

Thanks again...I'm gonna print this and read again...

Thanks for the link BC.
I'll check em out.

So does that one caliper slider never get cleaned and lubed? I would like to know if the caliper and bracket separate and if so...how?

And I’m in Elgin. I have access to GM service info if needed.

Thanks CMNTMXR57.
Have you done rear brakes on this car and do you know what I have to do to seperate the caliper from the pad bracket so I can service that slider? I did not go back out there last night and just figured I would tackle it tonight. If I have to I will just do as above and swivel the caliper out, but I would like to clean and apply fresh lube to that slider.
Also...anyone know what kind of spanner wrench I need to get the caliper back in?
Thanks!
Kurt

I have not yet done brakes on this car. Although my front passenger one squeals like a pig once the brakes get warm, so fairly soon, I am going to get them apart and put anti-squeal on the backs of the pads to shut them up.

There is a quick trick if the caliper mounting bolts come loose but you can’t get them off (the bolts out and the caliper off the mounting bracket), chances are, they’re loose, but caught up inside that rubber boot somehow just spinning. This is a common problem on Malibu’*, Grand Am’*, Grand Prix’* and a few other FWD GM vehicles.

Locate a little collar like sleeve located between the caliper and the bracket. It should have some sort of flat sides to it so that you can hold onto it with a wrench or pliers. Hold that steady while you unscrew the bolt itself.

If it’* a matter of having the bolts out and you just can’t get the caliper off the mounting bracket, that’* simply a matter of having to work it off with force. Trust me, I’ve been there, it’* a PITA! If possible, try pushing the piston back into the caliper (like mentioned above in Blu’* description with a C-Clamp). This will give you more wiggle room to work it off. It sometimes helps to tilt it off and out from either the top or bottom of the caliper (whichever has more initial wiggle room to start with) then pull it out/off the rest of the way. For example, if the top is loose and the bottom won’t really budge, work the top off, tilt it out and away, and eventually the bottom will come to. Aside from being hung up on the rotor, be careful of those little rubber according moisture protection tubes that allow the caliper to float freely when assembled. They’ll just pop out of their recessed holes on the caliper bracket and then will pop back in with a small flat head screwdriver on reassembly.

When pushing back the piston after cleaning and starting to reassemble things, A) Take the lid off of the reservoir on the master cylinder and B) it doesn’t hurt to crack the bleeder screw open. This way as you push back the piston, the retreating fluid, which may be contaminated with whatever, will go out and not back into the line and/or any screen/filter clogging it up resulting in poor brake pressure once everything is back together. This is an actual service procedure on GM trucks when pushing back the piston and doesn’t hurt to make it common practice on all vehicles GM or not. This isn’t a replacement for bleeding them mind you, so you’ll still want to do that. Bleeding the system is meant to be bleeding FROM the master cylinder.

Oh yea, pick up some of that anti-squeal stuff. CRC makes it, it comes in a little bottle, it’* orange in color. It pours like water but soon dries to a gooey, rubbery like substance that keeps the pads from vibrating which is what actually causes the squealing.

When you pull the bolts out, you’ll note they have grease on them. Clean off the old grease and then put some fresh clean grease on. I use a good high temp, wheel bearing type of grease that’* just good to have around in the garage for many purposes. Then once you re-install everything, that freshly greased slider bolt will allow for the caliper to float in and out upon brake application and release.