If your parking brake isn't working correctly, here's what you should do:
1. Check the brake shoes: The most likely cause is worn-out brake shoes inside the rear drums. These need replacing. This is a more involved job requiring the removal of the rear wheels and brake drums.
2. Check the parking brake cable: Though less common, the cable itself could be frayed, broken, or stretched. This would require inspection and potentially replacement. You'll need to trace the cable from the parking brake lever to the rear brakes to check for damage.
3. Check the parking brake lever: Make sure the lever itself is operating correctly and not sticking.
4. Inspect for leaks: Check for brake fluid leaks at the rear wheel cylinders or elsewhere in the brake system. Leaks would indicate a bigger problem.
In short: You can't simply "adjust" the parking brake on a 2002 Chevy Tahoe like you could on older cars. If it's not working properly, it requires a more thorough inspection and likely repair or replacement of components. This is a job best left to a qualified mechanic unless you have experience working on brakes. Improper brake repair can be dangerous.
