2000 GMC Yukon Owner's Manual - Page 110

Level Control (If Equipped) Self-Adjusting The self-adjusting rear suspension is available on C/K 1500 vehicles and is available with the premium smooth ride suspension package. This type of level control will provide a leveled riding position as well as improved handling under a variety of passenger and loading conditions. A hydraulic pump inside each rear shock absorber raises the rear of the vehicle to the proper height, based on inputs from the road surface, while the vehicle is being driven. It takes approximately 2 miles (3.2 km) of driving for the leveling to complete, depending on the road surface conditions. If the loaded vehicle is not moved for approximately twelve hours, the leveling system may bleed down to a lower height. This can be especially apparent is a trailer is left attached to a parked vehicle for long periods of time. The vehicle must be driven to re-level the vehicle. If a self-equalizing hitch is being used, the vehicle should be driven approximately 2 miles (3.2 km) with the trailer prior to adjusting (leveling) the hitch. 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. t 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 to 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. 2-33