This is for the 2001 suburban with a 7200 GVW. The parking brake consist of a band that is behind the rotor. The inside of the disc rotor is like the inside of a brake drum. The band is expanded when you set the brake and contacts the inside of the rotor. The park brake has no self adjustment mechanism. It must be adjusted manually. I guess I should tell you to first jack the rear of vehicle up on a hard flat surface and support it with substantial jack stands. Stand back out of the way and shake the vehicle to veryify that it is not going to fall on you while your head is up in the wheel well. Remove the rear wheels. Remove the brake caliber by removing 2 bolts on the inside of the caliper with an 18mm socket. Remove the caliper and support it. Never let a caliper hang by the hose. Remove the rotor. It should just slide off. If the parking brake drum surface is worn to the point of cutting a groove the brake band will hang in the groove, and it may be quiet a chore to get it off without breaking something. There is no provision to release the tension on the band while the rotor is on. After you get the rotor off, you will notice a little adjustment star wheel directly on the oposite side of where the parking brake cable attaches, just like the old style drum type brake self adjustment mechanisms. On the left side it is on the top, and on the right side it is on the bottom. There is a spring clip behind the adjustment wheel which allows the wheel to turn in one direction only, to expand the band. You can take a screwdriver and turn the wheel. It will click with each notch. This expands the band. This is a trial and error procedure. After about every three clicks, slide the rotor back on and make sure that the rotor will go on and still turn freely. Once you get it tight enough that you can't turn the rotor or it won fit, you will have to take a second screwdriver and depress the clip behind the adjustment wheel while turning the wheel in the oposite direction to retract the band. If the parking brake drum surface is grooved, you will be better off replacing the rotor and the brake band. My auto parts store told me they had received a TSB instructing them not to turn the drum portion of the rotor. My rear rotors were 52.99 each. Don't expect the parking brake to lock the rear wheels.
When adjusted properly, they should keep a stopped vehicle from rolling, but that's about it. I found that there is a fine line between too tight and too loose. The parking brake band is only about an inch wide, and does not have a lot of pad on it. Driving with the parking brake on just one time is all it takes to wear the lining to the point that it will be ineffective. On my suburban, if you drive off with the parking brake set, once you get to about 18 mph, a lot of warning chimes start going off and red warning lights on the dash flash. Also, the headlights will not come on if the brake is set. There were complaints about the ineffectiveness of these brakes, and NHTSA did an investigation but closed the case without a recall.