Brakes Failed problems of the 2009 Chevrolet Tahoe Hybrid

Summary: brake failure in a Tahoe Hybrid while driving, my chevy Tahoe Hybrid experienced almost total brake failure. Over several days, the brakes had became more and more "grabby. " on the day of the total brake failure, with normal pressure applied to the brake pedal there would be almost no braking power. But with just a little bit more pressure applied the brakes would suddenly engage with full braking power. Suddenly, this unhappy performance degraded into almost total brake failure. It felt like I had less than 1/30th of the normal braking power. I was not going fast, and nothing was in front of me to hit, and I was a block from my destination, so I continued slowly. Before calling for a tow I let the car sit, and I tried the car again. Surprisingly, I had my grabby brakes back! I nursed the truck to the dealership where they reloaded the computer program that controls the brakes. I experienced a second total failure just as I arrived at the dealership. The techs reloaded the computer program that controls the braking system and this addressed the problem, mostly. The brakes don't exactly feel like they used to, and there is a little bit of "sudden grab" to them, but the mechanic indicated that the performance is normal for a hybrid system.