Brakes; Regenerative Braking - GMC Sierra Hybrid 2011 Owner's Manual

9-8 Driving and Operating
A number displays next to the M,
indicating the current gear that has
been selected. The number
displayed in the gear indicator is the
highest gear that can be used. The
vehicle can automatically shift to
lower gears as it adjusts to driving
conditions. When 3 (Third) is
selected, 1 (First) through 3 (Third)
gears are automatically shifted by
the vehicle, but 4 (Fourth) cannot be
used until it is selected.
The Range Selection Mode controls
the vehicle and engine speed while
driving down a hill or towing a trailer,
by allowing you to select a desired
range of gears.
When you move the shift lever into
M, the transmission will default to
M4. In this gear range, effective
engine braking occurs at speeds
above 72 km/h (45 mph).
Pushing the minus ( ) button on the
shift lever reduces the gear range.
In the M3 gear range, effective
engine braking occurs at speeds
above 56 km/h (35 mph).
In the M2 gear range, effective
engine braking occurs at speeds
above 40 km/h (25 mph).
In the M1 gear range, effective
engine braking occurs at speeds
above 16 km/h (10 mph).
When operating in M (Manual
Mode), Auto Stop is disabled. For
better vehicle efficiency, operate the
vehicle in D (Drive) not
M (Manual Mode).
Cruise control can be used while
using the Range Selection Mode.

Brakes

Regenerative Braking

Regenerative braking is a hybrid
technology that enables the electric
drive motor to operate as a
generator when coasting or braking.
Energy from the moving vehicle
recharges the hybrid battery.
The hydraulic disc brakes work with
the regenerative braking to insure
effective braking, such as when a
high braking demand is requested.
The braking system is computer
controlled and blends the
regenerative braking with the
conventional hydraulic disc brakes
to meet any requirements for
deceleration. The controller
interprets the braking request and
uses regenerative braking,
conventional hydraulic braking or a
combination of both as necessary.