2001 GMC Savana Van Owner's Manual - Page 221

Run your engine only as long as you must. This saves fuel. When you run the engine, make it go a little faster than just idle. That is, push the accelerator slightly. This uses less fuel for the heat that you get and it keeps the battery (or batteries) charged. You will need a well-charged battery (or batteries) to restart the vehicle, and possibly for signaling later on with your headlamps. Let the heater run for a while. If you have a diesel engine, you may have to run it at a higher speed to get enough heat. Then, shut the engine off and close the window almost all the way to preserve the heat. Start the engine again and repeat this only when you feel really uncomfortable from the cold. But do it as little as possible. Preserve the fuel as long as you can. To help keep warm, you can get out of the vehicle and do some fairly vigorous exercises every half hour or so until help comes. Recreational Vehicle Towing Your vehicle was not designed to be towed with all four wheels on the ground. If your vehicle must be towed, see "Towing Your Vehicle" in the Index. NOTICE: Towing your vehicle with all four wheels on the ground will damage drivetrain components. 4-29