See also:

Engine Exhaust
WARNING Engine exhaust contains carbon monoxide (CO) which cannot be seen or smelled. Exposure to CO can cause unconsciousness and even death. Exhaust may enter the vehicle if: • The vehicle idle ...

Engine Oil
For diesel engine vehicles, see “Engine Oil” in the Duramax Diesel Supplement. To ensure proper engine performance and long life, careful attention must be paid to engine oil. Following these si ...

Footnotes — Maintenance Schedule Additional Required Services — Severe
a) Or every two years, whichever comes first. b) 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 properl ...