I have an '04 Silverado with the same issue. In addition to worn pads, the cable assembly can stretch over time. There is an adjustment to tighten it, but after 17 years, they are either rusted frozen or maxed out and the cable is still too stretched and loose. I do recommend inspecting your cable and seeing if it needs to be replaced or there are areas where you can tighten the tension. Until then, throw a wheel chock in the back of your truck for when you park on a hill. Good luck.
I bought a 2005 Yukon, 218,000 miles, and the parking brake cable in the cab was missing so I replaced it. Then I realized the parking brake doesn't engage enough to stop it from rolling from even a slight sloping hill, entirely empty. So something is not working right. How should I confirm what is broken? Are there other components that can fail that would cause the parking brake not to work? Should I disassemble both rear wheel rotors and visually checked it out? Thanks!
Got an '03 Yukon XL, have worked on this twice til I'm blue in the face & can Not get it to hold even in neutral. Has to be something wrong w/ the cable assembly, any idea/s ? thanks, - take care