1995 Buick Riviera Owner's Manual - Page 209

Rocking your vehicle to get it out: NOTICE: Spinningyourwheelscandestroypartsofyour vehicle as well as the tires. If you spin the wheels too fastwhile shifting your transaxle back and forth, you can destroy your transaxle. For information about using tire chains on your vehicle, see "Tire Chains" in the Index. First, turn your steering wheel left and right. That will clear the area around your front wheels. If your vehicle has traction control, you should turn the system off. (See "Traction Control System" in the Index.) Then shift back and forth between REVERSE (R) and a forward gear, spinning the wheels as little as possible. Release the accelerator pedal while you shift, and press lightly on the accelerator pedal when the transaxle is in gear. If that doesn't get youout after a few tries, you may need to be towed out. If you do need to betowed out, see "Towing Your Vehicle" inthe Index. 5-28