Chevrolet Tahoe Owner's Manual page 357

On all vehicles, the Engine Oil Life
System can be reset as follows:
1. Turn the ignition to ON/RUN with
the engine off.
2. Fully press the accelerator pedal
slowly three times within
five seconds.
3. Display the OIL LIFE
REMAINING on the DIC. If the
display shows 100%, the system
is reset. See
If the vehicle has a CHANGE
ENGINE OIL SOON message and it
comes back on when the vehicle
is started and/or the OIL LIFE
REMAINING is near 0%, the engine
oil life system has not been reset.
Repeat the procedure.
It is usually not necessary to check
the transmission fluid level. The
only reason for fluid loss is a
transmission leak or overheated
transmission. If a small leak is
suspected, then use the following
checking procedures to check the
.
fluid level. However, if there is a
large leak, then it may be necessary
to have the vehicle towed to a
dealer and have it repaired before
driving the vehicle further.
Change the fluid and filter at the
scheduled maintenance intervals
listed in
. Be sure to use the
transmission fluid listed in
Before checking the fluid level,
prepare the vehicle as follows:
1. Start the engine and park the
vehicle on a level surface. Keep
the engine running.
.