Engine Oil Life System; Automatic Transmission; Fluid - GMC Duramax Diesel 2015 Owner's Manual

Engine Oil Additives/Engine
Oil Flushes
Do not add anything to the oil. The
recommended oils with the API
service symbol are all that is
needed for good performance and
engine protection.
Engine oil system flushes are not
recommended and could cause
engine damage not covered by the
vehicle warranty.
What to Do with Used Oil
Used engine oil contains certain
elements that can be unhealthy for
your skin and could even cause
cancer. Do not let used oil stay on
your skin for very long. Clean your
skin and nails with soap and water,
or a good hand cleaner. Wash or
properly dispose of clothing or rags
containing used engine oil. See the
manufacturer's warnings about the
use and disposal of oil products.
Used oil can be a threat to the
environment. If you change your
own oil, be sure to drain all the oil
from the filter before disposal. Never
dispose of oil by putting it in the
trash or pouring it on the ground,
into sewers, or into streams or
bodies of water. Recycle it by taking
it to a place that collects used oil.

Engine Oil Life System

The engine oil life system calculates
engine oil life based on vehicle use
and displays the CHANGE ENGINE
OIL SOON message when it is time
to change the engine oil and filter.
The oil life system should be reset
to 100% only following an oil
change. See Engine Oil Life
System in the owner manual.

Automatic Transmission

Fluid

When to Check and Change
(Pickup Models)
Change the fluid and filter at the
intervals listed. See Maintenance
Schedule on page 11-3.
Vehicle Care
And be sure to use the transmission
fluid listed in Recommended Fluids
and Lubricants on page 11-8.
How to Check
Because this operation can be a
little difficult, the decision may be
made to have this done at the
dealer.
If the decision is made to perform
this operation, be sure to follow all
the instructions here, or a false
reading on the dipstick could result.
Caution
Too much or too little fluid can
damage the transmission. Too
much can mean that some of the
fluid could come out and fall on
hot engine parts or exhaust
system parts, starting a fire. Too
little fluid could cause the
transmission to overheat. Be sure
to get an accurate reading if
checking the transmission fluid.
10-9