See also:

What to Add
Use only new DOT 3 brake fluid from a sealed container. See Recommended Fluids and Lubricants on page 11‑12. Always clean the brake fluid reservoir cap and the area around the cap before re ...

Engine Overheating
If the vehicle has the Duramax® Diesel engine, see the Duramax Diesel Supplement for more information. The vehicle has several indicators to warn of engine overheating. There is a coolant temperatu ...

Footnotes — Maintenance Schedule Additional Required Services — Normal
a) Check all fuel and vapor lines and hoses for proper hook-up, routing, and condition. Check that the purge valve, if the vehicle has one, works properly. Replace as needed. b) Or every four years, ...