Torque Converter Clutch
A feature designed to improve fuel economy has been
included in the automatic transmission on your vehicle.
A clutch within the torque converter engages automati-
cally at calibrated speeds. This may result in a slightly
different feeling or response during normal operation in
the upper gears. When the vehicle speed drops or during
some accelerations, the clutch automatically disengages.
NOTE:
•The torque converter clutch will not engage (and
66RFE-equipped trucks will not shift to sixth gear),
until the transmission fluid and engine coolant are
warm [usually after 1 to 3 miles (2 to 5 km) of driving].
Because engine speed is higher when the torque con-
verter clutch is not engaged, it may seem as if the
transmission is not shifting properly when cold. This is
normal. Using the Electronic Range Select (ERS) shift control, when the transmission is sufficiently warm,
will demonstrate that the transmission is able to shift
into and out of Overdrive.
• If the vehicle has not been driven for several days, the
first few seconds of operation after shifting the trans-
mission into gear may seem sluggish. This is due to the
fluid partially draining from the torque converter into
the transmission. This condition is normal and will not
cause damage to the transmission. The torque con-
verter will refill within five seconds after starting the
engine.
FOUR-WHEEL DRIVE OPERATION — IF
EQUIPPED
Four-wheel drive trucks are equipped with either a
manually shifted transfer case or an electronically shifted
transfer case. Refer to the operating instructions for your
transfer case, located in this section for further informa-
tion.
5
STARTING AND OPERATING 311
Manually Shifted Transfer Case — If Equipped
The transfer case provides four mode positions.
•Two-wheel drive high range (2H)
• Four-wheel drive high range (4H)
• Neutral (N)
• Four-wheel drive low range (4L)
This transfer case is intended to be driven in the 2H
position for normal street and highway conditions such
as dry, hard surfaced roads.
When additional traction is required, the 4H and 4L
positions can be used to lock the front and rear drive-
shafts together and force the front and rear wheels to
rotate at the same speed. This is accomplished by simply
moving the shift lever to the desired positions once the
appropriate speed and gear requirements are met refer to
“Shifting Procedure – Manually Shifted Transfer Case” in this section for further information. The 4H and 4L
positions are intended for loose, slippery road surfaces
only. Driving in the 4H and 4L positions on dry, hard
surfaced roads may cause increased tire wear and dam-
age to the driveline components.
The “Transfer Case Position Indicator Light” in the
instrument cluster will alert the driver that the vehicle is
in four-wheel drive and that the front and rear drive-
shafts are locked together. This light will illuminate when
the transfer case is shifted into either the 4H or 4L
position. There is no light for the 2H or NEUTRAL
positions on some models.
When operating your vehicle in 4L, the engine speed is
approximately three times that of the 2H or 4H positions
at a given road speed. Take care not to overspeed the
engine and do not exceed 25 mph (40 km/h).
312 STARTING AND OPERATING
2H Or 4H To 4L
With the vehicle rolling at 2 to 3 mph (3 to 5 km/h), shift
the transmission into NEUTRAL. While the vehicle is
coasting at 2 to 3 mph (3 to 5 km/h), shift the transfer
case lever firmly to the desired position. Do not pause in
transfer case NEUTRAL.
NOTE:
•Pausing in transfer case NEUTRAL in vehicles
equipped with an automatic transmission may require
shutting the engine OFF to avoid gear clash while
completing the shift. If difficulty occurs, shift the
transmission into NEUTRAL, hold foot on brake, and
turn the engine OFF. Make shift to the desired mode.
• Shifting into or out of 4L is possible with the vehicle
completely stopped, however difficulty may occur due to the mating clutch teeth not being properly aligned.
Several attempts may be required for clutch teeth
alignment and shift completion to occur. The preferred
method is with the vehicle rolling 2 to 3 mph (3 to
5 km/h). Avoid attempting to engage or disengage 4L
with the vehicle moving faster than 2 to 3 mph (3 to
5 km/h).
• Do not attempt to shift into or from 4L while the
transmission is in gear.
Transfer Case Position Indicator Light
The “Transfer Case Position Indicator Light” in the
instrument cluster is used to alert the driver that the front
axle is fully engaged and all four wheels are driving.
5
STARTING AND OPERATING 315
the control knob back to the current position, wait five
seconds, and retry selection. To find the shift require-
ments, refer to theShifting Procedure for your transfer
case, located in this section.
The “SVC 4WD Warning Light” monitors the electronic
shift four-wheel drive system. If this light remains on
after engine start up or illuminates during driving, it
means that the four-wheel drive system is not function-
ing properly and that service is required.
WARNING!
Always engage the parking brake when powering
down the vehicle if the “SVC 4WD Warning Light” is
illuminated. Not engaging the parking brake may
allow the vehicle to roll, which may cause personal
injury. NOTE:
Do not attempt to make a shift while only the
front or rear wheels are spinning, as this can cause
damage to driveline components.
When operating your vehicle in 4WD LOW, the engine
speed is approximately three times that of the 2WD or
4WD LOCK positions at a given road speed. Take care
not to overspeed the engine and do not exceed 25 mph
(40 km/h).
Proper operation of four-wheel drive vehicles depends
on tires of equal size, type and circumference on each
wheel. Any difference in tire size can cause damage to the
drivetrain.
Because four-wheel drive provides improved traction,
there is a tendency to exceed safe turning and stopping
speeds. Do not go faster than road conditions permit.
318 STARTING AND OPERATING
towing behind another vehicle. Refer to “Recreational
Towing” in “Starting and Operating” for further infor-
mation.
Shifting Procedure
NOTE:
•If any of the requirements to select a new transfer case
position have not been met, the transfer case will not
shift. The position indicator light for the previous
position will remain ON and the newly selected posi-
tion indicator light will continue to flash until all the
requirements for the selected position have been met.
To retry a shift: return the control knob back to the
original position, make certain all shift requirements
have been met, wait five seconds and try the shift
again. •
If all the requirements to select a new transfer case
position have been met, the current position indicator
light will turn OFF, the selected position indicator light
will flash until the transfer case completes the shift.
When the shift is complete, the position indicator light
for the selected position will stop flashing and remain
ON.
2WD To 4WD LOCK
Rotate the 4WD control switch to the desired position.
Shifts between 2WD and 4WD LOCK can be done with
the vehicle stopped or in motion. With the vehicle in
motion, the transfer case will engage/disengage faster if
you momentarily release the accelerator pedal after turn-
ing the control switch. If the vehicle is stopped, the
ignition switch must be in the ON position with the
engine either running or off. This shift cannot be com-
pleted if the ignition switch is in the ACC position.
320 STARTING AND OPERATING
NOTE:The four-wheel drive system will not allow shifts
between 2WD/4WD LOCK if the front and/or rear
wheels are spinning (no traction). In this situation, the
selected position indicator light will flash and the origi-
nal position indicator light will remain ON. At this time,
reduce speed and stop spinning the wheels to complete
the shift.
2WD Or 4WD LOCK To 4WD LOW
NOTE: When shifting into or out of 4WD LOW some
gear noise may be heard. This noise is normal and is not
detrimental to the vehicle or occupants.
Shifting can be performed with the vehicle rolling 2 to
3 mph (3 to 5 km/h) or completely stopped. You can use
either of the following procedures:
Preferred Procedure
1. With the engine running, slow the vehicle to 2 to 3 mph (3 to 5 km/h). 2. Shift the transmission into NEUTRAL.
3. While still rolling, rotate the transfer case control
switch to the desired position.
4. After the desired position indicator light is ON (not flashing), shift the transmission back into gear.
Alternate Procedure
1. Bring the vehicle to a complete stop.
2. With the ignition switch in the ON position and the engine running, shift the transmission into NEUTRAL.
3. Rotate the transfer case control switch to the desired position.
4. After the desired position indicator light is ON (not flashing), shift the transmission back into gear.5
STARTING AND OPERATING 321
NOTE:
•If Steps 1 or 2 of either the Preferred or Alternate
Procedure are not satisfied prior to attempting the
shift, then the desired position indicator light will flash
continuously while the original position indicator light
is ON, until all requirements have been met.
• The ignition switch must be in the ON position for a
shift to take place and for the position indicator lights
to be operable. If the ignition switch is not in the ON
position, the shift will not take place and no position
indicator lights will be on or flashing.
LIMITED-SLIP DIFFERENTIAL
The limited-slip differential provides additional traction
on snow, ice, mud, sand and gravel, particularly when
there is a difference between the traction characteristics
of the surface under the right and left rear wheels. During normal driving and cornering, the limited-slip unit per-
forms similarly to a conventional differential. On slip-
pery surfaces, however, the differential delivers more of
the driving effort to the rear wheel having the better
traction.
The limited-slip differential is especially helpful during
slippery driving conditions. With both rear wheels on a
slippery surface, a slight application of the accelerator
will supply maximum traction. When starting with only
one rear wheel on an excessively slippery surface, slight
momentary application of the parking brake may be
necessary to gain maximum traction.WARNING!
On vehicles equipped with a limited-slip differential
never run the engine with one rear wheel off the
ground since the vehicle may drive through the rear
(Continued)
322 STARTING AND OPERATING
CAUTION!(Continued)
•Driving through standing water may cause damage
to your vehicle’s drivetrain components. Always
inspect your vehicle’s fluids (i.e., engine oil, trans-
mission, axle, etc.) for signs of contamination (i.e.,
fluid that is milky or foamy in appearance) after
driving through standing water. Do not continue to
operate the vehicle if any fluid appears contami-
nated, as this may result in further damage. Such
damage is not covered by the New Vehicle Limited
Warranty.
• Getting water inside your vehicle’s engine can
cause it to lock up and stall out, and cause serious
internal damage to the engine. Such damage is not
covered by the New Vehicle Limited Warranty.
POWER STEERING
The standard power steering system will give you good
vehicle response and increased ease of maneuverability
in tight spaces. The system will provide mechanical
steering capability if power assist is lost.
If for some reason the power assist is interrupted, it will
still be possible to steer your vehicle. Under these condi-
tions, you will observe a substantial increase in steering
effort, especially at very low vehicle speeds and during
parking maneuvers.
NOTE:
• Increased noise levels at the end of the steering wheel
travel are considered normal and do not indicate that
there is a problem with the power steering system.
• Upon initial start-up in cold weather, the power steer-
ing pump may make noise for a short amount of time.
This is due to the cold, thick fluid in the steering
326 STARTING AND OPERATING