Interesting comment from your dealership about replacing the entire assembly. I wonder if that's why some members have reported issues after having the switch replaced.Thanks everyone for your information. I had checked the Chevrolet.com website using my VIN before I went to the dealer and the only open recall I had was the loss of antifreeze without leak one. That was done at the same time they put in the vac. switch. The dealer did tell me that now when they replace the switch, they must replace the entire assembly (with the tube also) or else people are having repeat failures on the switch. Why do you think that is the case? Changing those parts fixed the symptoms and my brakes are back to normal, thankfully. Thanks again for all your help!