GMC TopKick 2007 Owner's Manual page 273

However, your engine oil and filter must be
changed at least once a year and at this time
the system must be reset. Your dealer has
GM-trained service people who will perform this
work using genuine GM parts and reset the
system. It is also important to check your oil
regularly and keep it at the proper level.
If the system is ever reset accidentally, you
must change your oil at 3,000 miles (5 000 km)
since your last oil change. Remember to reset the
oil life system whenever the oil is changed.
How to Reset the Engine Oil Life
System
The Engine Oil Life System calculates when to
change your engine oil and filter based on vehicle
use. Anytime your oil is changed, reset the system
so it can calculate when the next oil change is
required. If a situation occurs where you change
your oil prior to a change engine oil light being
turned on, reset the system.
To reset the change engine oil light, do the
following:
1. Turn the ignition key to RUN with the
engine off.
2. Fully press and release the accelerator pedal
slowly three times within 10 seconds.
If the change engine oil light flashes for
five seconds, the system is resetting.
3. Turn the key to OFF.
If the change engine oil light comes back on when
you start your vehicle, the engine oil life system
has not reset. Repeat the procedure.
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