LOCKING DIFFERENTIALS

On some electric vehicles with dual rear motors, such as select GMC HUMMER EV models, a mechanical locker is not required. The vehicle uses software to virtually lock the two motors that power the rear wheels together. The result is essentially the same as a mechanical locker. The front locker is an electronically controlled, mechanical locking differential.

To Engage the Rear Locker:

1. Press the corresponding centerstack button that shows a single lock over the rear axle.

To Engage the Front Locker:

1. Make sure vehicle is in Terrain Mode by using the Driver Mode Selector dial. In Terrain Mode, both the front and rear axles can be locked for maximum traction.
2. To engage the front locker, press and hold the centerstack button that shows locks over both axles for 5 seconds. If the rear axle was not already locked, it will lock together with the front axle locker.

Note: The front locker automatically disengages at speeds above 15 mph.

Note: The rear locker is available at speeds of up to 50 mph in Terrain Mode.

Note: The lockers can be manually disengaged with a push of their corresponding centerstack button.