FAILURE OF AUTO PARKING BRAKE SYSTEM ON CHEVROLET P-30 CHASSIS FOR MOTORHOMES--FAILURE OF SENSOR PRESSURE SWITCH WHICH APPLIES THE PARKING BRAKE, NO PRAWL IN THE TRANSMISSION FOR "PARK"-CAUSING THE PARKING BRAKE, OR EMERGENCY BRAKE TO BE APPLIED WHILE VEHICLE IS MOVING--NO MANUAL RELEASE--GM NO LONGER SUPPLIES REPLACEMENT PARTS FOR UNIT MANUFACTURED IN 1993--MANY MOTORHOME OWNERS ARE EXPERIENCING THIS PROBLEM--SEE RVFORUM.COM FOR COMMENTS==P-30 AUTO BRAKE=MAJOR COMPONENT FOR SYSTEM RENDERS THE UNIT USELESS WITH NO REPAIR--WHAT GIVES. *TR