Upon start up, after sitting for several hours or overnight, the car fails to stop properly for the first minute. This is dangerous as the pedal is soft and inconsistent and stopping times and distances are substantially greater than normal or acceptable tolerances. It is dangerous to both people and property as the car does not stop as it should. I have experienced tapping into garage doors due to the failure of the car to stop properly. In the event that a person would have been present, it could have been deadly. I have also experienced numerous close calls when maneuvering in garages. A friend has the same truck and has asked if I experienced the problem with stopping the truck after start up. I took the car to go GMC in golden Colorado on multiple occassions. They downplay the event and state that they cannot get the truck to duplicate the problem when testing. After multiple trips to the dealer, they are now saying that it takes a minute or two for the vacum booster, or something like that, to pressurize and the brakes are working "normally." If this is normal, it does not conform with standard driving behavior. Having to wait for your brakes to pressurize for a minute of so is not normal. Thanks.

- Vail, CO, USA