Very Cold Weather Operation

If the vehicle is driven in very cold temperatures and cannot get a winterized Number 2-Diesel that has been adapted to cold weather, a Number 1 - Diesel may be supplemented. Only use Number 1 - Diesel when the temperature falls below -18°C (0°F), because the fuel economy is not as good as that of Number 2 - Diesel fuel. To prevent waxing or gelling of the diesel fuel, use 50% Number 1 - Diesel in the fuel tank and add a container of GM approved Diesel Fuel Treatment part number 88861698. The additive is a preventative and must be added when filling the tank and before any waxing or gelling occurs.

In cold weather, the fuel filter may become clogged (waxed). To unclog the filter, move the vehicle to a warm garage area and warm the filter to a temperature between 0 - 10°C (32 - 50°F). Replacing the filter is not necessary.