When stuck in mud, sand, snow, or ice conditions, do not spin your vehicle’s wheels faster than 30 mph (48 km/h) or for longer than 30 seconds continuously without stopping when you are stuck.

WARNING!
Fast spinning tires can be dangerous. Forces generated by excessive wheel speeds may cause tire damage or failure. A tire could explode and injure someone.
Do not spin your vehicle’s wheels faster than 30 mph (48 km/h) or for more than 30 seconds continuously when you are stuck, and do not let anyone near a spinning wheel, no matter what the speed.