2008 Dodge Ram 2500 Pickup Owner Manual Diesel - Page 279

STARTING AND OPERATING 277 Block Heater Usage A. Temperatures below 0°F (-18°C) • Block Heater Required for 15W-40 • Block Heater Recommended for 5W-40 B. Temperatures below - 20°F (-29°C) • Block Heater Required for 5W-40 Winter Front Usage If a winter front or cold weather cover is to be used, a percentage of the total grille opening area must be left uncovered to provide sufficient air flow to the charge air cooler and automatic transmission oil cooler. The percentage of opening must be increased with the increasing ambient air temperature and/or engine load. If the cooling fan can be heard cycling frequently, increase the size of the opening in the winter front. A suitable cold weather cover is available from your Mopar௡ dealer. Battery Blanket Usage A battery loses 60% of its cranking power as the battery temperature decreases to 0°F (-18°). For the same decrease in temperature, the engine requires twice as much power to crank at the same RPM. The use of 120 VAC powered battery blankets will greatly increase starting capability at low temperatures. Suitable battery blankets are available from your authorized Mopar௡ dealer. Arctic Operation Where there are no provisions to keep the engine warm when it is operating in ambient temperatures consistently below (-10°F/-23°C), use 5W-40 synthetic engine oil and fuel that meets the requirements in Section 7, "Maintenance Procedures," Engine Oil Selection. Engine Warm-Up Avoid full throttle operation when the engine is cold. When starting a cold engine, bring the engine up to operating speed slowly to allow the oil pressure to stabilize as the engine warms up. 5