Full-Time Four-Wheel Drive. HUMMER H2 2009

For 1990-2009 cars only

Makes 🢒 HUMMER 🢒 2009 🢒 H2 🢒 Driving Your Vehicle 🢒 Your Driving, the Road, and the Vehicle 🢒 Full-Time Four-Wheel Drive

The Full-Time Four-Wheel Drive transfer case is designed to constantly send the engine's driving power to all four wheels for extra traction. To get the most out of Full-Time Four-Wheel Drive, you must be familiar with its operation.

Notice: Driving on pavement in Four-Wheel High Lock or Four Wheel Low Lock for extended periods may cause premature wear on the vehicle powertrain and tires. Do not drive in Four-Wheel High Lock or Four-Wheel Low Lock on pavement for extended periods.

Transfer Case Dial

The transfer case dial is located to the right of the instrument panel cluster. Use this switch to shift into and out of the different Full-Time Four-Wheel Drive modes.

The transfer case is a part of the Full-Time Four-Wheel Drive system and allows the following four different modes of operation:

4 (Full-Time Four-Wheel Drive): This setting is used for driving in most street and highway situations. It can be used for light or variable off-road conditions.

4 (Four-Wheel-High Lock): Use this mode when you need extra traction in most off-road situations such as sand, mud, snow, or level, rocky trails.

4 (Four-Wheel-Low Lock): This mode delivers extra torque to all four wheels and is used for extreme off-road conditions. Choose Four-Wheel-Low Lock while driving off-road in deep sand, mud, or snow and climbing or descending steep hills. When in this mode you can also choose to lock the rear axle for additional traction in extreme off-road situations. See Locking Rear Axle.

Notice: Operating the vehicle in Four-Wheel-Low Lock above 50 mph (80 km/h) for any extended period of time could cause damage to the transfer case. Do not operate the vehicle in Four-Wheel-Low Lock above 50 mph (80 km/h) for extended periods.

Caution: Shifting the transfer case to N (Neutral) can cause the vehicle to roll even if the transmission is in P (Park). You or someone else could be seriously injured. Be sure to set the parking brake before placing the transfer case in N (Neutral). See Parking Brake .

N (Neutral): Shift the transfer case to N (Neutral) only when towing the vehicle. See Recreational Vehicle Towing or Towing Your Vehiclefor more information.

Indicator lights in the dial show which mode you are in. The indicator lights will come on briefly when you turn on the ignition and one will stay on. If the lights do not come on, take the vehicle to your dealer/retailer for service. An indicator light will flash while shifting the transfer case. It will remain on when the shift is complete. If the transfer case cannot make a requested shift, it will return to the last chosen setting.

If the SERVICE 4WD message stays on, you should take the vehicle to your dealer/retailer for service. See "Service 4WD message" under Driver Information Center (DIC).

Shifting between Four-Wheel High and Four-Wheel-High Lock

With the vehicle traveling less than 40 mph (64 km/h), turn the dial to the Four-Wheel High or Four-Wheel-High Lock position. The indicator light on the dial will flash while shifting. It will remain on when the shift is complete.

It may be necessary to drive backwards for a short distance of 25 feet (7.5 m) to get the lock feature to disengage.

Shifting into Four-Wheel-Low Lock

To shift into Four-Wheel-Low Lock, the ignition must be in ON/RUN and the vehicle must be stopped or moving less than 3 mph (5 km/h) with the transmission in N (Neutral). The preferred method for shifting into Four-Wheel Low Lock is to have the vehicle moving 1 to 2 mph (1.6 to 3.2 km/h). Turn the dial to the Four-Wheel-Low Lock position. You must wait for the Four-Wheel-Low Lock indicator light on the dial to stop flashing and remain lit before shifting the transmission in gear.

When the transfer case is shifted into the Four-Wheel-Low Lock position a StabiliTrak® indicator light will come on to show that the system has been turned off and a message will show in the DIC. See DIC Warnings and Messages for more information.

Notice: Shifting the transmission into gear before the indicator light stops flashing could cause damage to the transfer case. Always wait until the indicator light stops flashing before putting the transmission back in gear.

It is normal for the vehicle to have engagement noise and bump when shifting between Four-Wheel Low Lock, Full-Time Four-Wheel Drive or Four-Wheel-High Lock ranges or from N (Neutral) with the engine running.

If the Four-Wheel-Low Lock position is selected when the vehicle is in gear and/or moving, the Four-Wheel Low Lock indicator light will flash for 15 seconds and not complete the shift unless the vehicle is moving less than 3 mph (5 km/h) and the transmission is in N (Neutral). After 15 seconds the transfer case will return to the setting last chosen.

Shifting Out of Four-Wheel Low Lock

To shift from Four-Wheel-Low Lock to Full-Time Four-Wheel Drive or Four-Wheel-High Lock, the vehicle must be stopped or moving less than 3 mph (5 km/h) with the transmission in N (Neutral) and the ignition in ON/RUN. The preferred method for shifting out of Four-Wheel-Low Lock is to have the vehicle moving 1 to 2 mph (1.6 to 3.2 km/h). Turn the dial to the Full-Time Four-Wheel Drive or Four-Wheel-High Lock position. You must wait for the Full-Time Four-Wheel Drive or Four-Wheel-High Lock indicator light to stop flashing and remain lit before shifting the transmission into gear.

If the Full-Time Four-Wheel Drive or Four-Wheel-High Lock position is selected when the vehicle is in gear and/or moving, the Full-Time Four-Wheel Drive or Four-Wheel-High Lock indicator light will flash for 30 seconds but will not complete the shift unless the vehicle is moving less than 3 mph (5 km/h) and the transmission is in N (Neutral).

Shifting into Neutral

To shift the transfer case to N (Neutral) do the following:

Make sure the vehicle is parked so that it will not roll.
Set the parking brake and apply the regular brake pedal. See Parking Brake.
Start the vehicle or turn the ignition to ON/RUN.
Put the transmission in N (Neutral).
Shift the transfer case to Full-Time Four-Wheel Drive.
Turn the transfer case dial clockwise to N (Neutral) position. The transfer case will not shift to N (Neutral) unless this position is held for 10 seconds. The N (Neutral) light will come on and then the dial can be slowly released. The dial will be in the Four-Wheel Low Lock position but the transfer case will be in N (Neutral) with the N (Neutral) light on.
If the engine is running, make sure that the transfer case is in N (Neutral) by shifting the transmission to R (Reverse) for one second, then shift the transmission to D (Drive) for one second.
Turn the ignition to ACC/ACCESSORY, which will turn the engine off.
Place the transmission shift lever in P (Park).
Release the parking brake prior to moving the vehicle.
Turn the ignition to LOCK/OFF.

Shifting Out of Neutral

To shift out of N (Neutral) do the following:

Set the parking brake and apply the regular brake pedal.
Shift the transmission to N (Neutral) and turn the ignition to ON/RUN with the engine off.
Turn the transfer case dial to Full-Time Four-Wheel Drive, Four-Wheel High Lock or Four-Wheel Low Lock.

After the transfer case has shifted out of N (Neutral) the N (Neutral) light will go out.

Release the parking brake prior to moving the vehicle.

Notice: Shifting the transmission into gear before the requested mode indicator light has stopped flashing could damage the transfer case. To help avoid damaging the vehicle, always wait for the mode indicator lights to stop flashing before shifting the transmission into gear.

Start the engine and shift the transmission to the desired position.