Engine Oil Life System; Engine Oil Additives; When To Change Engine Oil - GMC T-Series 2007 Owner's Manual

•
SAE 10W-40
As shown in the viscosity chart, SAE 10W-40
is best for your vehicle. When it is very
cold, below 0°F (−18°C), you should use
SAE 5W-40 to improve cold starting.
These numbers on the oil container show
its viscosity, or thickness. Do not use other
viscosity oils such as SAE 10W-30 or
SAE 20W-50.
Look for this on the oil container, and use only
those oils that display this logo.
This doughnut-shaped
logo (symbol) is used on
most oil containers to
help you select the
correct oil. It means that
the oil has been certified
by the American
Petroleum Institute.

Engine Oil Additives

Do not add anything to the oil. The recommended
oils with the API service symbol are all you
need for good performance and engine protection.
When to Change Engine Oil (Vehicles
Without the Engine Oil Life System)
Change the engine oil and filter every 15,000 miles
(24 000 km), or every 12 months, or every
750 hours of engine operation, whichever occurs
first. See Scheduled Maintenance on page 295.

Engine Oil Life System

When to Change Engine Oil

If your vehicle has the Engine Oil Life System,
it has a computer system that lets you know
when to change the engine oil and filter. This is
based on injection timing, engine load and engine
temperature, and not on mileage. Based on driving
conditions, the mileage at which an oil change will
be indicated can vary considerably. For the oil life
system to work properly, you must reset the system
every time the oil is changed.
209