See also:

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, ...

Under the Hood
The Yukon Hybrid uses a two-mode hybrid system. The system augments the SUV's V-8 engine with two electric motors, both powered by a 300-volt battery pack. A cylinder-deactivation system cuts powe ...

Driving on Grades
Reduce speed and shift to a lower gear before starting down a long or steep downgrade. If the transmission is not shifted down, the brakes might get hot and no longer work well. Vehicles can tow in D ...