Engine Coolant Heater

The engine heater can provide easier starting and better fuel economy during engine warm-up in cold weather conditions at or below −18°C (0°F). Vehicles with an engine heater should be plugged in at least four hours before starting.

An internal thermostat in the plug-end of the cord may exist which will prevent engine coolant heater operation at temperatures above −18°C (0°F).

If the vehicle has a diesel engine, see the Duramax Diesel supplement for more information.

See also:

When to Check and Change Automatic Transmission Fluid
A good time to check the automatic transmission fluid level is when the engine oil is changed. Change the fluid and filter at the intervals listed in Maintenance Schedule on page 11‑3 and be su ...

Engine Coolant Temperature Gauge
Metric English This gauge measures the temperature of the vehicle's engine. If the indicator needle moves to the hot side of the gauge toward the colored line, the engine is too hot. If ...

Checking Engine Oil
It is a good idea to check the engine oil level at each fuel fill. In order to get an accurate reading, the vehicle must be on level ground. The engine oil dipstick handle is a yellow loop. See En ...