Are the removal bolts on the brake caliper the 5/8 or the 12mm? (2003 Yukon Denali)

checked brake hoses if it is ok, check brakes shoes clipper may be while fixing it is not placed properly. even then it is not ok then let me clear is there any accident from back side hit. reply

Brake rotor and front or rear?

Okay, remove the wheel then remove the brake caliper and move to side do not allow to hang on the brake hose, use a hook to hang off spring or set aside. next remove the caliper bracket, two bolts at rear of bracket to remove it.
next you will use a hammer to remove the rotor.

NOTE: the way the brake rotor was designed was a bad one the hub in which the rotor slides over and the wheel studs slide into holes on the rotor is bad the hub diameter is almost the same size as the diameter of the seat of the rotor that slide over the hub and what happens is sometimes the rust build up on the rotor seat locks the brake rotor on the hub. i do not know if you are reusing the rotors or replacing them, no sure what job you are doing . the rotors to take off you will need to tap on the rear of them with a little force and turn, hit and turn. you will need to see if they break free or if hard beating and spraying into the rear of them is needed with wd40.
Alot of these rotors also have two threaded hole on the face of the rotor near the studs so that you can screw two bolts into holes to help pull them. use wire to tie caliper up and also use a c-clamp to push piston into calipe to remove caliper if needed, Do not remove brake hose, there is no need to open system, here is a picture of the rotor coming of the hub, also there may be clips on the stud holding rotor on remove them use cutters or pry off do not need to reuse , they are to help in holding the rotor on during asm, if you want you can buy them and reinstall them but never reuse them.

Yes you will need to remove the caliper and the bracket for the caliper. I know it is a poor design compared to fords

1. Release the park brake.
2. Raise and suitably support the vehicle. Refer to Vehicle Lifting.
3. Remove the tire and wheel assembly.
4. Mark the relationship of the rotor to the hub.
5. Remove the brake caliper bracket mounting bolts.

Notice: Support the brake caliper with heavy mechanic's wire, or equivalent, whenever it is separated from it's 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.

1. Remove the brake caliper and brake caliper bracket as an assembly and support with heavy mechanic's wire or equivalent. DO NOT disconnect the hydraulic brake flexible hose from the caliper.
2. Remove the rotor retaining push nuts from the wheel studs, if applicable.
3. It may be necessary to strike the end of the hub or the rotor with a deadblow hammer to separate the rotor from the hub.
4. Remove the rotor by slowly fuming the rotor while pulling the rotor away from the axle.

Installation Procedure

Notice: Whenever the brake rotor has been separated from the wheel bearing flange, clean any rust or foreign material from the mating surface of the rotor and flange with the J42450 hub cleaning kit. Failure to do this may result in increased lateral runout of the rotor and brake pulsation.

1. Use the J42450-A to clean all rust and contaminants from the mating surface of the hub flange.
2. Use the J41013 to clean all rust and contaminants from the inside diameter of the hub section of the brake rotor to prevent any foreign material from getting between the brake rotor and the hub flange.
3. Install the rotor by slowly fuming the rotor while pushing the rotor towards the axle.
4. Install the caliper and the bracket as an assembly to the vehicle.
5. Perform the following procedure before installing the caliper bracket mounting bolts.

• Remove all traces of the original adhesive patch.
• Clean the threads of the bolt with brake parts cleaner or the equivalent and allow to dry.
• Apply Threadlocker GM P/N 12345493 (Canadian P/N 10953488) to the threads of the bolt.

Notice: Refer to Fastener Notice in Service Precautions.

1. Install the caliper bracket mounting bolts.

• For the 15 Series, tighten the brake caliper bracket mounting bolts to 175 Nm (129 ft. lbs.).
• For the 25 series, tighten the brake caliper bracket mounting bolts to 300 Nm (221 ft. lbs.).

1. Install the tire and wheel assembly.
2. Lower the vehicle.
3. With the engine OFF, gradually apply the brake pedal to approximately 2/3 of its travel distance.
4. Slowly release the brake pedal.
5. Wait 15 seconds, then repeat steps 9-10 until a firm pedal is obtained. This will properly seat the brake caliper pistons and brake pads.
6. Fill the master cylinder reservoir to the proper level with clean brake fluid.

The rear caliper cradle bolts are 18mm. A 19 may round the bolts off a bit.As far as them wearing unevenly we see this alot on the dual piston calipers.This may be due to rust underneath where the pads sit on the cradle. On the caliper cradle you will see some silver tin caliper hardware where the pads sit remove these and check for rust that may have built up benath these and clean if necessary. Once those are clean apply a thin coat of caliper lube then reinstall the caliper hardware. Make sure to also lubricate the hardware with lube before reinstalling your pads.Last but not least apply lubricant to the caliper guide pins.This will reduce that uneven wear you were referring to.

These use a seperate drum brake inside the rotor. The caliper will come off with the removal of 2 bolts. The caliper comes up, push the piston in using a "C" clamp or large channel lock pliers. Simply slide out the pads and replace as necessary. Use a silicone grease on the slide pins and on the back of the pads to prevent squeeks. Professionally I would use AC Delco pads. Anything else could create more noises and other issues! Let me know if you need diagrams or anything else.

The only special tool i've needed when doing brakes on a truck like yours is a TORX socket for the rear caliper bolts. Is this what you are trying to do? I'm sure GM makes a special tool just for that, but i've used a regular torx socket with a removable bit. Then used a closed end wrench on the bit and double wrenched it for extra leverage as that bolt is on there tight.

if that is the problem...I thought so too, was the pump itself.....

2003 gmc sierra


it is located inside the hub, remove the calipers and the rotor, should be inside the hub, with a wire and plug comming from it...

Allen wrench or socket, usually 3/8"

after the calipers and brackets are off, the parking brake shoe may be holding it on. if it is,try to loosen the parking brake adjustment if you can get to it, if not, just pry the rotor off, if it has a big lip on it, it will need rotors and parking brake shoes anyhow.