Today I decided to take off my wheels, clean the inside and reinstall them and torque them down to 76 ft-lbs myself..
The front ones came off fine - the wheel locks are indeed, a little under torque.
The back wheels were super over torque, including the wheel lock. I had to stand on the wrench to get the nuts off. No such luck with the lock. When I stand on it, the key slips off. The key and the lock are a bit stripped.
I could not get the locks off. I went to a coworker's house down the street. He has a compressor and an impact wrench. The wrench puts me at a much better position, I was able to hold the key down to the lock. Guess what, the impact wrench went out of torque. Neither back wheel lock moved. I will have to go to another coworker's house next weekend, who has bigger, more torquey impact wrench.
On some studs, I was not able to tighten the nuts back by hand. The threads look pretty sorry. I think the damage was done by the tire shop using impact wrenchs to tighten lug nuts. I think I will have to run a die over the studs, to fix the threads. I hate to have to replace the studs.
The guy who rotated my tires last at Discounted Tires, must had his rear impact wrench set at max. Perhaps after using it to free someone else's seized up nuts, reversed it and used it to tighten mine...