See also:

When to Add Engine Oil
If the oil is below the L mark for the L6 engine or the cross-hatched area at the tip of the dipstick for the V8 engine, you will need to add at least one quart/liter of oil. But you must use the ...

Gasoline Octane
If the vehicle has the 3.9L V6 engine (VIN Code 1) or the 3.9L V6 engine (VIN Code M), use regular unleaded gasoline with a posted octane rating of 87 or higher. If the octane rating is less tha ...

Transferring Service
Push to request account transfer eligibility information. The Advisor can assist in canceling or removing account information. If OnStar receives information that vehicle ownership has chan ...