Four problems related to power train have been reported for the 2004 Chevrolet Avalanche. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2004 Chevrolet Avalanche based on all problems reported for the 2004 Avalanche.
The brake pressure modulator valve leaks the transmission has problems and service airbags is on.
Vehicle looses power and brakes go out then dies,doesn't matter speed. If slowing down and press the brakes, the locks, lights, and security goes crazy. This is dangerous as it is in intersections and caution for collision. The vehicle has to be off for a time frame and restarts fine and can go. Happened when coming from ramp and in middle of road with semi truck coming down by us.
4x4 transmission began locking and slipping. Developed a distinctive "clunking" sound when shifting between gears. Now most noticeable between second and third. Additional grinding sound occurs when driving. Noticeable at all speeds.
Drove off a parking lot at about 20mph and the transmission quit. Reverse works and all the low gears work out not on automatic mode.