RepairPal Expert Overview
A problem with the hydro-boost system may reduce braking assist and slightly increase the steering effort while braking.
Please contact your GM dealer. They will check to see if your specific vehicle is affected and advise you on what to do next. Always have your vehicle identification number (VIN) handy when you call.
The hydro-boost housing relief valve bore may be out of specification. The seal may fracture as a result, which may reduce braking assist and slightly increase the steering effort while braking. Under certain conditions, more braking effort will be required to stop the vehicle. Dealers will replace the hydro-boost relief valve. The recall began June 18, 2004. The GM recall number is 04004.