Chevrolet 2007 HH7 Owner's Manual page 394

If the engine oil life system is ever reset
accidentally, you must service your vehicle within
3,000 miles (5 000 km) since your last service.
Remember to reset the oil life system whenever
the oil is changed. See Engine Oil Life System on
page 302 for information on the Engine Oil Life
System and resetting the system.
When the CHANGE OIL SOON message appears,
certain services, checks, and inspections are
required. Required services are described in the
following for "Maintenance I" and "Maintenance II."
Generally, it is recommended that your
first service be Maintenance I, your second
service be Maintenance II, and that you alternate
Maintenance I and Maintenance II thereafter.
However, in some cases, Maintenance II may be
required more often.
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Maintenance I — Use Maintenance I if the
CHANGE OIL SOON message comes on within
10 months since the vehicle was purchased
or Maintenance II was performed.
Maintenance II — Use Maintenance II if the
previous service performed was Maintenance I.
Always use Maintenance II whenever the
CHANGE OIL SOON message comes on
10 months or more since the last service or if the
message has not come on at all for one year.