Hummer 2010 H3 - Manual (Page 240)

9-56 Driving and Operating
To lock the front and rear axles:
1. Place the transfer case in the
4LO Lock mode. This is the
only mode which allows the
front and rear axles to lock.
See Four-Wheel Drive on
page 9‑46 for more information
regarding the transfer case and
4LO Lock mode.
2. Press the rear axle locking
button with the vehicle moving
less than 16 mph (26 km/h).
3. Wait for the light in the button
to stop flashing and remain
illuminated to show that the rear
axle is locked.
4. Press the front axle locking
button with the vehicle stopped
or moving less than 26 km/h
(16 mph).
5. Wait for the light in the button
to stop flashing and remain
illuminated to show that the front
axle is locked.
Notice: If you try to lock the axle
while the vehicle is stuck and the
tires are spinning, the vehicle's
drivetrain could be damaged.
The repairs would not be covered
by the vehicle warranty. Always
lock the axle before attempting
situations and/or navigating
terrain which could possibly
cause the vehicle to become
stuck.
Locking axles will be disengaged
when the wheel speed is greater
than 64 km/h (40 mph), if the
vehicle's battery is low and/or the
transfer case is shifted out of
4LO Lock mode.
Notice: If the vehicle's axle
is locked while driving on
pavement, the drivetrain could be
damaged. Repairs would not be
covered by the vehicle warranty.
Do not use the locking axle on
pavement. If four-wheel drive is
needed when traveling on
pavement, use only 4HI.