Ok folks got one I need educated on. Been a long tome since I've done my own work, so I've never come across this. Picked up a 2000 denali that runs pretty good and figured I'd do the work myself starting with the brakes. Put the whole thing up on stands for ease and proceeded to remove the rear wheels. Put the lugnut wrench on a lugnut and the whole wheel spun freely! Same on both sides. Yes it was in park. Started it, put it in each gear and everything worked. Reverse, foreward gears, brakes stopped the wheels. Put it back in park, wheels spun free when trying to remove lugnuts again. Is there something I don't know?