Brake Sensor problems of the 2005 Cadillac Escalade

February 14, 2016 I was driving to work going about 50 miles per hour upon approaching 60 the vehicle begin to lose power so I steered over to the side of the highway and hit the onstar button to tell them that I was losing power and that would they run a diagnostic they stated that would. They stated also what they are going to check, braking system, engine, transmission etc. When they came back online me not know what they really did check I was told that all was a green light, so I proceed to continue on my way to work, but it happen again and I contacted them again and was told the same thing. Never once did they diagnostic only meant that they was just checking for codes and it was not a true diagnostic check. They also never offer to tow the vehicle home or to the dealer. I was able to get the vehicle home and took it to the first mechanic and was told that the yaw rate sensor needed replaced at $500 something didn't seem right so I took it to a gm certified mechanic and was told it was the hydo-boost, pressure hoses needed replaced at $2600 along on the phone back and forth with on star which claimed responsibility on star stated to me that gm tech wanted the vehicle taken to the dealership and that they would pay for the diagnosis to see what was the problem. So gm came and pick the vehicle up and transported to bommorito Cadillac of which they inspected the vehicle and report back to on star which stated that they wasn't responsible and that they believed that gm should handle it from here. To make a long story short gm claimed no responsibility for this even though you guy's and consumer affairs warned them about the issue with the braking system before and they done nothing about it even though it was a safety issue. My complaint that this issues should not be my responsibility nor the cost cause they new the potential of this failure.