Dt*: the contact stated while driving 20 mph, the power assist steering and the power assist brakes failed simultaneously, causing a loss of vehicle control. the vehicle was towed to a service dealer who determined the power steering pump and booster had failed, along with the booster that led to the power assist brake system.
2004 chevy suburban 2500 series with quadrasteer. the rear wheel steering faults approximately every 5 miles, often when exiting a turn. this can leave the rear wheels full left (or right) if the turn was tight causing the vehicle to crab down the road sideways. if the road is not wide and the driver is not extremely aware a sideswipe accident could easily occur. the rear wheels slowly self center after 10 to 15 seconds. vehicle has been back to the dealer many times. they either say they have replaced a sensor, tightened a loose connection, or no problem found. sometimes it will be ok for 20 miles or so but the problem always recurs. unable to get it fixed. *tr