2004 GMC Yukon Owner's Manual - Page 360

Level Control Automatic Level Control The automatic level control rear suspension is available on C/K 1500 vehicles and comes as a part of the Autoride™ suspension, if equipped. This type of level control is fully automatic and will provide a better leveled riding position as well as better handling under a variety of passenger and loading conditions. An air compressor connected to the rear shocks will raise or lower the rear of the vehicle to maintain proper vehicle height. The system is activated when the ignition key is turned to RUN and will automatically adjust vehicle height thereafter. The system may exhaust (lower vehicle height) for up to ten minutes after the ignition key has been turned off. You may hear the air compressor operating when the height is being adjusted. If a self-equalizing hitch is being used, it is recommended to allow the shocks to inflate, thereby leveling the vehicle prior to adjusting the hitch. Autoride™ If equipped, the Autoride™ feature will provide a superior vehicle ride and handling under a variety of passenger and loading conditions. The system is fully automatic and uses a computer controller to continuously monitor vehicle speed, wheel to body position, lift/dive and steering position of the vehicle. The controller then sends signals to each shock absorber to independently adjust the damping level to provide the optimum vehicle ride. Autoride™ also interacts with the tow/haul switch that, when engaged, will provide additional control of the shock absorbers. This additional control results in better ride and handling characteristics when the vehicle is loaded or towing a trailer. See Tow/Haul Mode Light on page 3-54 for more information. Trailer Recommendations You must subtract your hitch loads from the Cargo Weight Rating (CWR) for your vehicle. CWR is the maximum weight of the load your vehicle can carry. It doesn't include the weight of the people inside. But you can figure about 150 lbs. (68 kg) for each seat. The total cargo load must not be more than your vehicle's CWR. 4-62