will be automatically lowered to NRH. Off-Road 1
may not be available due to vehicle payload, an
EVIC/DID message will be displayed when this oc-
curs. Refer to “Electronic Vehicle Information Center
(EVIC) or Driver Information Display (DID)” in “Un-
derstanding Your Instrument Panel” for further infor-
mation.
• Off-Road 2 (OR2) (Raises the vehicle approximately
2 in [51 mm]) – This position is intended for off-
roading use only where maximum ground clearance is
required. To enter OR2, push the “Up” button twice
from the NRH position or once from the OR1 position
while vehicle speed is below 20 mph (32 km/h). While
in OR2, if the vehicle speed exceeds 25 mph (40 km/h)
the vehicle height will be automatically lowered to
OR1. Off-Road 2 may not be available due to vehicle
payload, an EVIC/DID message will be displayed
when this occurs. Refer to “Electronic Vehicle Informa-
tion Center (EVIC) or Driver Information Display (DID)” in “Understanding Your Instrument Panel” for
further information.
CAUTION!
If the vehicle is in OFFROAD1 or OFFROAD2 set-
ting, be aware of your surroundings, you may not
have the clearance required for certain areas and
vehicle damage may occur.
• Aero Mode (Lowers the vehicle approximately .6 in
[15 mm]) – This position provides improved aerody-
namics by lowering the vehicle. The vehicle will
automatically enter Aero Mode when the vehicle
speed remains between 62 mph (100 km/h) and
66 mph (106 km/h) for greater than 20 seconds or if the
vehicle speed exceeds 66 mph (106 km/h). The vehicle
will return to NRH from Aero Mode if the vehicle
5
STARTING AND OPERATING 547
NOTE:The vehicle will automatically enter Aero Mode
when the vehicle speed remains between 62 mph
(100 km/h) and 66 mph (106 km/h) for greater than 20
seconds or if the vehicle speed exceeds 66 mph
(106 km/h).
• Normal Ride Height (NRH) – This is the standard
position of the suspension and is meant for normal
driving.
• Off-Road (OR) (Raises the vehicle approximately 1 in
[26 mm]) – This position is intended for off-roading
use only where maximum ground clearance is re-
quired. To enter OR, push the “Up” button once from
the NRH position while vehicle speed is below 20 mph
(32 km/h). While in OR, if the vehicle speed exceeds
25 mph (40 km/h) the vehicle height will be automati-
cally lowered to NRH. Off-Road may not be available
due to vehicle payload, an EVIC/DID message will be
Air Suspension Switch
1 — Up Button
2 — Down Button
3 — Entry/Exit Mode Indicator Lamp (Customer selectable)
4 — Aero Mode Indicator Lamp (Customer selectable)
5 — Normal Ride Height Indicator Lamp (Customer selectable)
6 — Off-Road Indicator Lamp (Customer selectable)
5
STARTING AND OPERATING 559
Crossing Logs
To cross a log, approach it at a slight angle (approxi-
mately 10 to 15 degrees). This allows one front tire to be
on top of the log while the other just starts to climb the
log. While climbing the log, modulate your brake and
accelerator to avoid spinning the log out from under your
tires. Then ease the vehicle off the log using your brakes.
CAUTION!
Do not attempt to cross a log with a greater diameter
than the running ground clearance or the vehicle will
become high centered.
Getting High Centered
If you get hung up or high centered on an object, get out
of the vehicle and try to determine what the vehicle is
hung up on, where it is contacting the underbody andwhat is the best direction to recover the vehicle. Depend-
ing on what you are in contact with, jack the vehicle up
and place a few rocks under the tires so the weight is off
of the high point when you let the vehicle down. You can
also try rocking the vehicle or winching the vehicle off
the object.
CAUTION!
Winching or rocking the vehicle off hard objects
increases the risk of underbody damage.
Hill Climbing
Hill climbing requires good judgment and a good under-
standing of your abilities and your vehicle’s limitations.
Hills can cause serious problems. Some are just too steep
to climb and should not be attempted. You should always
5
STARTING AND OPERATING 577
crossing is the water depth, current and bottom con-
ditions. On soft bottoms the vehicle will sink in,
effectively increasing the water level on the vehicle. Be
sure to consider this when determining the depth and
the ability to safely cross.
• Crossing Puddles, Pools, Flooded Areas Or Other
Standing Water – Puddles, pools, flooded or other
standing water areas normally contain murky or
muddy waters. These water types normally contain
hidden obstacles and make it difficult to determine an
accurate water depth, approach angle, and bottom
condition. Murky or muddy water holes are where
you want to hook up tow straps prior to entering. This
makes for a faster, cleaner and easier vehicle recovery.
If you are able to determine you can safely cross, than
proceed using the low and slow method.CAUTION!
Muddy waters can reduce the cooling system effec-
tiveness by depositing debris onto the radiator.
• Crossing Ditches, Streams, Shallow Rivers Or Other
Flowing Water – Flowing water can be extremely
dangerous. Never attempt to cross a fast running
stream or river even in shallow water. Fast moving
water can easily push your vehicle downstream
sweeping it out of control. Even in very shallow water,
a high current can still wash the dirt out from around
your tires putting you and your vehicle in jeopardy.
There is still a high risk of personal injury and vehicle
damage with slower water currents in depths greater
than the vehicle’s running ground clearance. You
should never attempt to cross flowing water which is
deeper than the vehicle’s running ground clearance.
Even the slowest current can push the heaviest vehicle
582 STARTING AND OPERATING
While studded tires improve performance on ice, skid
and traction capability on wet or dry surfaces may be
poorer than that of non-studded tires. Some states pro-
hibit studded tires; therefore, local laws should be
checked before using these tire types.
Run Flat Tires — If Equipped
Run Flat tires allow you the capability to drive 50 miles
(80 km) at 50 mph (80 km/h) after a rapid loss of inflation
pressure. This rapid loss of inflation is referred to as the
Run Flat mode. A Run Flat mode occurs when the tire
inflation pressure is of/or below 14 psi (96 kPa). Once a
Run Flat tire reaches the run flat mode it has limited
driving capabilities and needs to be replaced immedi-
ately. A Run Flat tire is not repairable.
It is not recommended driving a vehicle loaded at full
capacity or to tow a trailer while a tire is in the run flat
mode.See the tire pressure monitoring section for more infor-
mation.
Spare Tires — If Equipped
NOTE:
For vehicles equipped with Tire Service Kit
instead of a spare tire, please refer to “Tire Service Kit” in
“What To Do In Emergencies” for further information.
CAUTION!
Because of the reduced ground clearance, do not take
your vehicle through an automatic car wash with a
compact or limited-use temporary spare installed.
Damage to the vehicle may result.
Spare Tire Matching Original Equipped Tire And
Wheel — If Equipped
Your vehicle may be equipped with a spare tire and
wheel equivalent in look and function to the original
654 STARTING AND OPERATING
To Stow The Flat Or Spare
NOTE:Vehicles equipped with aluminum wheels can-
not be stored under the vehicle because the wheel
retainer will not fit through the wheel pilot hole. Secure
the flat tire in the bed of the truck. Have the flat tire
repaired or replaced immediately.
WARNING!
A loose tire thrown forward in a collision or hard
stop could injure the occupants in the vehicle. Have
the deflated (flat) tire repaired or replaced immedi-
ately.
1. Turn the wheel so that the valve stem is facing the ground and toward the rear of the vehicle for conve-
nience in checking the spare tire inflation. Slide the
wheel retainer through the center of the wheel. 2. Lift the spare tire with one hand to give clearance to
tilt the retainer at the end of the cable and position it
properly across the wheel opening.
Reinstalling The Retainer
6
WHAT TO DO IN EMERGENCIES 745
9. Adjust the tire pressure when possible.
NOTE:Do not oil wheel studs. For chrome wheels, do
not substitute with chrome plated wheel nuts.
To Stow The Flat Or Spare
NOTE: Have the flat tire repaired or replaced immedi-
ately.
WARNING!
A loose tire thrown forward in a collision or hard
stop could injure the occupants in the vehicle. Have
the deflated (flat) tire repaired or replaced immedi-
ately.
1. Turn the wheel so that the valve stem is facing the ground and toward the rear of the vehicle for conve-
nience in checking the spare tire inflation. Slide the
wheel retainer through the center of the wheel. 2. Lift the spare tire with one hand to give clearance to
tilt the retainer at the end of the cable and position it
properly across the wheel opening.
Reinstalling The Retainer
6
WHAT TO DO IN EMERGENCIES 765