“1” First
For driving up very steep hills and for engine braking at
low speeds 25 mph (40 km/h) or less when going down
hill. To prevent excessive engine speed do not exceed 25
mph (40 km/h) in this range.
Overdrive Operation
The overdrive automatic transmission contains an elec-
tronically controlled fourth and fifth (if equipped) speed
(Overdrive). The transmission will automatically shift
from Drive to Overdrive if the following conditions are
present:
•the transmission selector is in Drive;
•the engine coolant has reached normal operating tem-
perature;
•vehicle speed is above approximately 30 mph (48
km/h);
•the “TOW/HAUL” switch has not been activated;
•transmission has reached normal operating tempera-
ture.
NOTE:If the vehicle is started in extremely cold tem-
peratures, the transmission may not shift into Overdrive
and will automatically select the most desirable gear for
operation at this temperature. Normal operation will
resume when the transmission fluid temperature has
risen to a suitable level. Refer also to the Note under
torque converter clutch, later in this section.
If the transmission temperature gets extremely hot, the
transmission will automatically select the most desirable
gear for operation at this temperature. If the transmission
temperature becomes hot enough the TRANS TEMP light
may illuminate and the transmission may downshift out
of Overdrive until the transmission cools down. After
cooldown, the transmission will resume normal opera-
tion.
STARTING AND OPERATING 261
5
The transmission will downshift from Overdrive to Drive
if the accelerator pedal is fully depressed at vehicle
speeds above approximately 35 mph (56 km/h).
When To Use “TOW/HAUL” Mode
When driving in hilly areas, towing a trailer, carrying a
heavy load, etc., and frequent transmission shifting oc-
curs, press the “TOW/HAUL” button. This will improveperformance and reduce the potential for transmission
overheating or failure due to excessive shifting. When
operating in “TOW/HAUL” mode, 5th gear (if
equipped) is disabled and 2-3 and 3-4 shift patterns are
modified. Shifts into Overdrive (4th gear) are allowed
during steady cruise (for improved fuel economy) and
automatic closed-throttle downshifts to 3rd gear (for
improved braking) will occur during steady braking.
The “TOW/HAUL” light will illuminate in the instru-
ment cluster to indicate when the switch has been
activated. Pressing the switch a second time restores
normal operation. If the “TOW/HAUL” mode is desired,
the button must be pressed each time the engine is
started.
Torque Converter Clutch
A feature designed to improve fuel economy is included
in all automatic transmissions. A clutch within the torque
converter engages automatically at a calibrated speed at
262 STARTING AND OPERATING
light throttle. It engages at higher speeds under heavier
acceleration. This may result in a slightly different feeling
or response during normal operation in high gear. When
the vehicle speed drops below a calibrated speed, or
during acceleration, the clutch automatically and
smoothly disengages. The feature is operational in Over-
drive and in Drive.
NOTE:The torque converter clutch will not engage
until the transmission fluid and engine coolant are warm
[usually after 1-3 miles (1.6 - 4.8 km) of driving]. Because
the engine speed is higher when the torque converter
clutch is not engaged, it may seem as if the transmission
is not shifting into Overdrive when cold. This is normal.
Pressing theTOW/HAULbutton will demonstrate that
the transmission is able to shift into and out of Overdrive.
NOTE:If the vehicle has not been driven in several
days, the first few seconds of operation after shifting the
transmission into gear may seem sluggish. This is due tothe fluid partially draining from the torque converter into
the transmission. This condition is normal and will not
cause damage to the transmission. The torque converter
will refill within five seconds of shifting from Park into
any other gear position.
FOUR-WHEEL DRIVE OPERATION
NV 144 Transfer Case Operating
Information/Precautions
The NV 144 is an electric shift transfer case and is
operated by the Four-Wheel-Drive (4WD) Control
Switch, which is located on the instrument panel.
The NV 144 transfer case provides 2 mode positions:
Four-Wheel Drive (4WD) and 4-Wheel-Drive Lock (4WD
LOCK).
The NV 144 transfer case is designed to be driven in for
4WD for normal street and highway conditions (all road
surfaces roads).
STARTING AND OPERATING 263
5
WARNING!
•BAS cannot prevent the natural laws of physics
from acting on the vehicle, nor can it increase
braking efficiency beyond that afforded by the
condition of the vehicle brakes and tires or the
traction afforded.
•The BAS cannot prevent accidents, including
those resulting from excessive speed in turns,
following another vehicle too closely, or hydro-
planing. Only a safe, attentive, and skillful driver
can prevent accidents.
•The capabilities of a BAS-equipped vehicle must
never be exploited in a reckless or dangerous
manner which could jeopardize the user ’s safety
or the safety of others.
TCS (Traction Control System)
This system monitors the amount of wheel spin of each of
the driven wheels. If wheel spin is detected, brake
pressure is applied to the slipping wheel(s) and engine
power is reduced to provide enhanced acceleration and
stability. A feature of the TCS system functions similar to
a limited slip differential and controls the wheel spin
across a driven axle. If one wheel on a driven axle is
spinning faster than the other, the system will apply the
brake of the spinning wheel. This will allow more engine
torque to be applied to the wheel that is not spinning.
This feature remains active even if TCS and ESP are in the
“Partial Off” mode. Refer to “ESP (Electronic Stability
Program)” in this Section of this manual. This brake
pressure modulation transfers drive torque from slipping
to non-slipping wheels to provide optimal forward trac-
tion.
STARTING AND OPERATING 281
5
conditions and more wheel spin than ESP would nor-
mally allow is required to gain traction. TSC (Trailer
Sway Control) is not available when the system is in the
Partial Offmode. To turn ESP on again, momentarily
depress the “ESP-Control OFF” Control Switch. This will
restore the normal “ON” mode of operation. ESP always
operates under braking, even with the switch in the
OFF-position.
WARNING!
In the Partial Off mode, the engine torque reduction
and stability features are desensitized. Therefore,
the enhanced vehicle stability offered by ESP is
unavailable.
NOTE:To improve the vehicle’s traction when driving
with snow chains, or starting off in deep snow, sand or
gravel, it may be desirable to switch to the “Partial Off”mode by pressing the ESP Control Switch. Once the
situation requiring ESP to be switched to the “Partial Off”
mode is overcome, turn ESP on by momentarily depress-
ing the “ESP Control Switch”. This may be done with the
vehicle is in motion.
4WD LOW Range
Partial Off
This is the normal operating mode for ESP in 4WD LOW.
Whenever the vehicle is started in 4WD LOW or the
transfer case (if equipped) is shifted from 4WD LOCK or
neutral to 4WD LOW, the ESP system will be in this
mode. In 4WD LOW, ESP function is desensitized until
the vehicle reaches a speed of 30 mph (48 km/h). At 30
mph (48 km/h) the normal ESP stability function returns
and the ESP/TCS Indicator Light” turns off. When the
vehicle speed drops below 25 mph (40 km/h) the ESP
system goes back to Partial Off. ESP is desensitized at low
vehicle speeds in 4WD LOW so that it will not interfere
STARTING AND OPERATING 285
5
with off road driving but ESP function returns to provide
the stability feature at speeds above 30 mph (48 km/h).
The ABS is in a special Off-Road mode that allows wheels
to lock at lower speeds if gravel is detected to shorten
stopping distances.
NOTE:When the vehicle is in 4WD LOW, a feature of
the ESP system remains active whether the ESP is on or
off. This feature functions similar to a limited slip differ-
ential and controls the wheel spin across an axle. If one
wheel on an axle is spinning faster than the other, the
system will apply the brake of the spinning wheel and
allow more engine torque to be applied to the wheel that
is not spinning.WARNING!
In the Partial Off mode, the engine torque reduction
and stability features are desensitized. Therefore,
the enhanced vehicle stability offered by ESP is
unavailable.
ESP/BAS Warning Lamp and ESP/TCS Indicator
Light
The malfunction indicator for the ESP is combined with
the BAS indicator. The yellow “ESP/BAS Warning
Lamp” and the yellow “ESP/TCS Indicator Light” in the
instrument cluster both come on when the ignition
switch is turned to the “ON” position. They should both
go out with the engine running. If the “ESP/BAS Warn-
ing Lamp” comes on continuously with the engine
running, a malfunction has been detected in either the
ESP or BAS system, or both. If this light remains on after
several ignition cycles, and the vehicle has been driven
286 STARTING AND OPERATING
Before raising the wheel off the ground, make sure that
the jack will not damage surrounding truck parts and
adjust the jack position as required.
4. By rotating the wheel wrench clockwise, raise the
vehicle until the wheel just clears the surface.
WARNING!
Raising the vehicle higher than necessary can make
the vehicle unstable and cause an accident. It could
slip off the jack and hurt someone near it. Raise the
vehicle only enough to remove the tire.
5. Remove the wheel nuts and pull the wheel off. Install
the spare wheel and wheel nuts with the cone shaped end
of the nuts toward the wheel. Lightly tighten the nuts. To
avoid risk of forcing the vehicle off the jack, do not fully
tighten the nuts until the vehicle has been lowered.
NOTE:Do not oil wheel studs. For chrome wheels, do
not substitute with chrome plated wheel nuts.
6. Using the wheel wrench, finish tightening the nuts in
a crisscross pattern. Correct nut tightness is 135 ± 10 ft.
lbs. (183 ± 14 N·m) dynamic torque. If in doubt about the
correct tightness, have them checked with a torque
wrench by your dealer or at a service station.
Rear Right Jacking Location
352 WHAT TO DO IN EMERGENCIES
•Do not change the thermostat for summer or winter
operation. If replacement is ever necessary, install
ONLY the correct type thermostat. Other designs may
result in unsatisfactory coolant performance, poor gas
mileage, and increased emissions.
Emission Related Components
Fuel System Hoses And Vapor/Vacuum Harnesses
When the vehicle is serviced for scheduled maintenance,
inspect surface of hoses and nylon tubing for evidence of
heat and mechanical damage. Hard and brittle rubber,
cracking, checking, tears, cuts, abrasions, and excessive
swelling suggest deterioration of the rubber. Particular
attention should be given to examining hose surfaces
nearest to high heat sources, such as the exhaust mani-
fold.
Insure nylon tubing in these areas has not melted or
collapsed.Inspect all hose clamps and couplings to make sure they
are secure and no leaks are present.
NOTE:Fluids such as oil, power steering fluid, and
brake fluid are used during assembly plant operations to
ease the assembly of hoses to couplings. Therefore, oil
wetness at the hose-coupling area is not necessarily an
indication of leakage. Actual dripping of hot fluid when
systems are under pressure (during vehicle operation),
should be noted before hose is replaced based on leakage.
You are urged to use only the manufacturer’s specified
hoses and clamps, or their equivalent in material and
specification, in any fuel system servicing. It is manda-
tory to replace all clamps that have been loosened or
removed during service. Care should be taken in install-
ing new clamps to insure they are properly torqued.
386 MAINTAINING YOUR VEHICLE