Displacement On Demand (Dod); Automatic Transmission Operation - GMC Envoy Owner's Manual

Displacement on Demand (DoD)

Your vehicle's engine may be equipped with
Displacement on Demand (DoD). This system allows
the engine to operate on either four or eight cylinders,
depending on your driving demands.
The system determines when to switch into and out of
the four-cylinder mode by first making sure that
certain enabling criteria are met, such as coolant and oil
temperatures, and the transmission being in either
THIRD (3) or FOURTH (4) gear.
When greater power demands are required, such as
accelerating from a stop, passing, or merging onto
a freeway, the system will maintain eight-cylinder
operation. When less power is required, such a cruising
at a constant vehicle speed, the system will
automatically enable the four-cylinder mode, allowing
your vehicle to achieve better fuel economy.

Automatic Transmission Operation

There are several different positions for your gear
shift lever.
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