
analyzing things such as vehicle speed, throttle positionand vehicle load. If the shift stabilization featuredetermines that a current vehicle speed cannot bemaintained, the transmission does not upshift andinstead holds the current gear. In some cases, this mayappear to be a delayed shift, however the transmissionis operating normally.
The vehicle's transmission uses adaptive shift controlsthat compares key shift parameters to pre-programmedideal shifts stored in the transmissions computer. Thetransmission constantly makes adjustments to improvevehicle performance according to how the vehicle isbeing used, such as with a heavy load or whentemperature changes. During this adaptive shift controlsprocess, shifting may feel different as the transmissiondetermines the best settings.
When temperatures are very cold, the Hydra-Matic®
6L80 automatic transmission's gear shifting may bedelayed providing more stable shifts until the enginewarms up. Shifts may be more noticeable with a coldtransmission. This difference in shifting is normal.
Driver Shift Control (DSC)
The vehicle has Driver Shift Control (DSC). DSCcontrols the vehicle's transmission and vehicle speedwhile driving down hill or towing a trailer by allowing youto select a desired range of gears.
To use this feature, do the following:
1. Move the shift lever to the M (Manual Mode).
2. Press the plus/minus button, to upshift or downshiftselecting the desired range of gears for currentdriving conditions.
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The DIC display will show the message MANUALSHIFT on the first line and the current gear will bedisplayed on the second line. SeeDriver InformationCenter (DIC)on page 4!41andDIC Operation andDisplayson page 4!41for more information. Thenumber displayed in the DIC is the highest gear thatcan be used. However, the vehicle can automaticallyshift to lower gears as it adjusts to driving conditions.This means that all gears below that number areavailable. When 5 (Fifth) is selected, 1 (First) through5 (Fifth) gears are automatically shifted by the vehicle,but 6 (Sixth) cannot be used until the plus/minus buttonlocated on the steering column lever is used to changeto the gear.
Grade Braking is not available when the Driver ShiftControl is active. SeeTow/Haul Modeon page 3!36formore information.
While using the DSC, cruise control and the tow/haulmode can be used.
Tow/Haul Mode
The vehicle has a tow/haul mode. The tow/haul modeadjusts the transmission shift pattern to reduce shiftcycling, providing increased performance, vehiclecontrol, and transmission cooling when towing orhauling heavy loads.
Press the button located on the end of the shift lever toturn the tow/haul on or off. When the tow/haul is on, alight on the instrument panel cluster will come on.
SeeTow/Haul Mode Lighton page 4!40for moreinformation.
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Also see“Tow Haul Mode”underTowing a Traileronpage 6!42for more information.
The tow/haul mode works with the Autoride®feature,if the vehicle has this, to enhance the ride whentrailering or with a loaded vehicle. SeeAutoride®onpage 6!42.
Grade Braking
The Grade Braking shift modes can be activated bypressing the button on the end of the shift control lever.While in Range Selection Mode , Grade Braking isdeactivated allowing the driver to select a desired rangeof gears.
Grade Braking is only active while the Tow/Haul Modeis selected and you are not in the Range SelectionMode. See“Tow/Haul Mode listed previously andAutomatic Transmission Operationon page 3!32formore information on the Range Selection Mode. GradeBraking assists in maintaining desired vehicle speedswhen driving on downhill grades by automaticallyimplementing a shift schedule that utilizes the engineand transmission to slow the vehicle. This reduces wearon the braking system and increases control of thevehicle. Grade Braking monitors vehicle speed,acceleration, engine torque and brake pedal usage.
Using this information, it detects when the vehicle is ona downhill grade and the driver desires to slow thevehicle by pressing the brake.
Also seeTowing a Traileron page 6!42for moreinformation.
Cruise Grade Braking
Cruise Grade Braking assists when driving on adownhill grade. It maintains vehicle speed byautomatically implementing a shift schedule that usesthe engine and the transmission to slow the vehicle.Cruise Grade Braking operates while Cruise Control isengaged in Tow/Haul mode to assist in maintainingvehicle speed under loaded vehicle conditions.It utilizes vehicle acceleration and deviation fromdesired speed to determine the correct gear for theoperating condition. If vehicle speed is above thedesired speed the transmission will downshift to slowthe vehicle. If vehicle speed is near or below desiredspeed the trans will upshift, allowing vehicle speedto increase.
While in the Range Select Mode (RSM) mode, cruisegrade braking is not available.
SeeAutomatic Transmission Operation on page 3!32.
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Parking Brake
Set the parking brake by holding the regular brakepedal down, then pushing down the parking brakepedal.
If the ignition is on, the brake system warning light willcome on. SeeBrake System Warning Lightonpage 4!33.
Notice:Driving with the parking brake on canoverheat the brake system and cause prematurewear or damage to brake system parts. Make surethat the parking brake is fully released and thebrake warning light is off before driving.
To release the parking brake, hold the regular brakepedal down, then push down momentarily on theparking brake pedal until you feel the pedal release.Slowly pull your foot up off the park brake pedal. If theparking brake is not released when you begin to drive,the brake system warning light will flash and a chimewill sound warning you that the parking brake is still on.
If you are towing a trailer and are parking on a hill, seeTowing a Trailer on page 6!42.
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Shifting Into Park
{WARNING:
It can be dangerous to get out of the vehicle if the
shift lever is not fully in P (Park) with the parking
brake firmly set. The vehicle can roll. If you have
left the engine running, the vehicle can move
suddenly. You or others could be injured. To be
sure the vehicle will not move, even when you are
on fairly level ground, use the steps that follow.
If you are pulling a trailer, seeTowing a Traileron
page 6!42.
1. Hold the brake pedal down, then set theparking brake.
2. Move the shift lever into the P (Park) position bypulling the shift lever toward you and moving it upas far as it will go.
3. Turn the ignition key to LOCK/OFF.
4. Remove the key and take it with you. If you canleave the vehicle with the ignition key in your hand,the vehicle is in P (Park).
Leaving the Vehicle With the Engine
Running
{WARNING:
It can be dangerous to leave the vehicle with the
engine running. The vehicle could move suddenly
if the shift lever is not fully in P (Park) with the
parking brake firmly set. And, if you leave the
vehicle with the engine running, it could overheat
and even catch fire. You or others could be
injured. Do not leave the vehicle with the
engine running.
If you have to leave the vehicle with the engine running,be sure the vehicle is in P (Park) and the parking brakeis firmly set. After the shift lever is moved into P (Park),hold the regular brake pedal down. Then, see if you canmove the shift lever away from P (Park) without firstpulling it toward you. If you can, it means that the shiftlever was not fully locked into P (Park).
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Running the Vehicle While Parked
It is better not to park with the engine running. But if youever have to, here are some things to know.
{WARNING:
Idling a vehicle in an enclosed area with poor
ventilation is dangerous. Engine exhaust may
enter the vehicle. Engine exhaust contains
Carbon Monoxide (CO) which cannot be seen or
smelled. It can cause unconsciousness and even
death. Never run the engine in an enclosed area
that has no fresh air ventilation. For more
information, seeEngine Exhaust on page 3!41.
{WARNING:
It can be dangerous to get out of the vehicle if the
automatic transmission shift lever is not fully in
P (Park) with the parking brake firmly set. The
vehicle can roll. Do not leave the vehicle when the
engine is running unless you have to. If you have
left the engine running, the vehicle can move
suddenly. You or others could be injured. To be
sure the vehicle will not move, even when you are
on fairly level ground, always set the parking
brake and move the shift lever to P (Park).
Follow the proper steps to be sure the vehicle will notmove. SeeShifting Into Park on page 3!39.
If parking on a hill and pulling a trailer, seeTowing aTrailer on page 6!42.
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Mirrors
Manual Rearview Mirror
Hold the inside rearview mirror in the center to move itfor a clearer view behind your vehicle. Adjust the mirrorto avoid glare from the headlamps behind you. Push thetab forward for daytime use and pull it for nighttime use.
Automatic Dimming Rearview Mirror
This vehicle may have an automatic dimming insiderearview mirror with OnStar®. It may also haveIntellibeam®. For more information on Intellibeam™, see“Intellibeam™Intelligent High!Beam Headlamp ControlSystem”underExterior Lampson page 4!11. For moreinformation on OnStar®, see the OnStar®owner's guide.
Automatic Dimming Mirror Operation
Automatic dimming reduces the glare of lights frombehind the vehicle. The dimming feature comes onand the indicator light illuminates each time thevehicle is started.
O(On/Off):Press to turn the dimming feature on or off.
Cleaning the Mirror
Do not spray glass cleaner directly on the mirror. Use asoft towel dampened with water.
Outside Power Foldaway Mirrors
Controls for the outsidepower foldaway mirrorsare located on the driverdoor armrest.
Mirror Adjustment
1. Press (C) to fold the mirrors out to thedriving position.
2. Press (D) to fold the mirrors in to thefolded position.
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The system can bedisabled by pressing therear park aid disablebutton located next tothe radio.
The indicator light will come on and PARK ASSIST OFFdisplays on the Driver Information Center (DIC) toindicate that URPA is off, seeDIC Warnings andMessages on page 4!48.
When the System Does Not Seem to
Work Properly
If the URPA system will not activate due to a temporarycondition, the messages PARK ASSIST OFF or PARKASSIST BLOCKED SEE OWNERS MANUAL will bedisplayed on the DIC.
SERVICE PARK ASSIST :If this message occurs, takethe vehicle to your dealer/retailer to repair the system.
PARK ASSIST OFF :This message occurs if the driverdisables the system.
PARKING ASSIST BLOCKED SEE OWNERSMANUAL :This message can occur under thefollowing conditions:
.The ultrasonic sensors are not clean. Keep thevehicle's rear bumper free of mud, dirt, snow, iceand slush. For cleaning instructions, seeWashingYour Vehicle on page 7!102.
.The park assist sensors are covered by frost orice. Frost or ice can form around and behind thesensors and may not always be seen; this canoccur after washing the vehicle in cold weather.The message may not clear until the frost or icehas melted.
.A trailer was attached to the vehicle, or a bicycle oran object was hanging out of the liftgate during thelast drive cycle. Once the attached object isremoved, URPA will return to normal operation.
.A tow bar is attached to the vehicle.
.The vehicle's bumper is damaged. Take the vehicleto your dealer/retailer to repair the system.
.Other conditions may affect system performance,such as vibrations from a jackhammer or thecompression of air brakes on a very large truck.
If the system is still disabled, after driving forward atleast 40 km/h (25 mph), take the vehicle to yourdealer/retailer.
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