Special Application Services
• Severe Commercial Use Vehicles Only: Lubricate chassis components every 5 000 km/3,000 mi.
• Have underbody flushing service performed once a year.
See also:
Power Liftgate Operation
On vehicles with a power liftgate, the vehicle must be in P (Park) to use the
power feature. The taillamps flash when the power liftgate moves.
Notice: If you open the liftgate without checking f ...
Engine Oil
For diesel engine vehicles, see “Engine Oil” in the Duramax Diesel Supplement.
To ensure proper engine performance and long life, careful attention must be paid to engine oil.
Following these si ...
Turn Signals When Towing a Trailer
The turn signal indicators on the instrument panel flash whenever signaling a
turn or lane change. Properly hooked up, the trailer lamps also flash, telling other
drivers the vehicle is turning, c ...





