All brakes stuck on

[starkey188]

It's the hydrabooster, just happened to my 2005. There was a recall on it in 2005 but GM wouldn't honer mine because it wasn't the correct vin number. They quoted 726.00 for a new one. I priced one at a auto store and got it for 200.00. I think they priced the whole master cylinder at GM. My hydrabooster was leaking a little. It took about 3 hours to change out. The hardest part is working under the dash. I'm still bleeding air out of the steering pump system. Hope that helps a little.

[IRA51]

Gm had big problems with the hydraboost units in 05 Avalanches ,my brother had his brand new 05 truck in to the dealer 6 times ,and they never could fix it in the 6 months he owned it . he traded it in on a ford after 5600 miles. As it turns out he likes his 05 Ford supercrew Lariat better that the Avalanche any way .