1996 GMC Suburban Owner's Manual - Page 201

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 awhile. 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 fdirly vigorous exercises everyhalf hour or so until help comes. Loading Your Vehicle u SEE OWNER'S MANUAL FOR ADDITIONAL IKFGRMATION / The CertificatiodTire label is found on the rear edge of the driver's door. The label shows the size of your original tires and the inflation pressures needed to obtain the gross weight capacity of your vehicle. This is called the GVWR (Gross Vehicle WeightRating). TheGVWR includes the weight of the vehicle, all occupants, fuel and cargo. 4-41