Gasoline Octane
Use regular unleaded gasoline with a posted octane rating of 87 or higher. If the octane rating is less than 87, you may notice an audible knocking noise when you drive, commonly referred to as spark knock. If this occurs, use a gasoline rated at 87 octane or higher as soon as possible.
If you are using gasoline rated at 87 octane or higher and you hear heavy knocking, your engine needs service.
See also:
What Kind of Engine Oil to Use
Look for three things:
• GM6094M
Use only an oil that meets GM Standard GM6094M.
• SAE 5W-30
SAE 5W-30 is best for the vehicle. These numbers
on an oil container show its viscosity, or thi ...
Rear Axle
When to Check Lubricant
It is not necessary to regularly check rear axle
fluid unless you suspect there is a leak or you hear
an unusual noise. A fluid loss could indicate a
problem. Have it inspe ...
TTY Users
OnStar has the ability to
communicate to the deaf,
hard-of-hearing, or speech-impaired
customers while in the vehicle. The
available dealer-installed TTY
system can provide in-vehicle
acce ...