See also:

Under the Hood
GM's two-mode hybrid system enables "full" hybrid operation with the capability to cruise on electric power up to 30 mph. The gas engine kicks in if more acceleration is needed, as well ...

Recommended Fluids and Lubricants
...

Customer Assistance for Text Telephone (TTY) Users (U.S. and Canada)
To assist customers who are deaf, hard of hearing, or speech impaired and who use Text Telephones (TTYs), GMC has TTY equipment available at its Customer Assistance Center. Any TTY user can communicat ...