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When parking on a hill, apply the parking brake before
shifting the transmission to PARK, otherwise the load on
the transmission locking mechanism may make it diffi-
cult to move the shift lever out of PARK. As an added
precaution, turn the front wheels toward the curb on a
downhill grade and away from the curb on an uphill
grade.
On four-wheel drive vehicles be sure that the transfer
case is in a drive position.
WARNING!
•Never use the PARK position as a substitute for the
parking brake. Always apply the parking brake
fully when parked to guard against vehicle move-
ment and possible injury or damage.
(Continued)
WARNING! (Continued)
•Your vehicle could move and injure you and others
if it is not in PARK. Check by trying to move the
shift lever out of PARK with the brake pedal
released. Make sure the transmission is in PARK
before leaving the vehicle.
• It is dangerous to shift out of PARK or NEUTRAL
if the engine speed is higher than idle speed. If
your foot is not firmly pressing the brake pedal, the
vehicle could accelerate quickly forward or in re-
verse. You could lose control of the vehicle and hit
someone or something. Only shift into gear when
the engine is idling normally and your foot is
firmly pressing the brake pedal.
(Continued)
234 STARTING AND OPERATING
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CAUTION!
•Before moving the shift lever out of PARK, you
must turn the ignition switch from the LOCK/OFF
position to the ON/RUN position, and also press
the brake pedal. Otherwise, damage to the shift
lever could result.
• DO NOT race the engine when shifting from
PARK or NEUTRAL into another gear range, as this
can damage the drivetrain.
The following indicators should be used to ensure that
you have engaged the transmission into the PARK posi-
tion:
• When shifting into PARK, pull the shift lever toward
you and move it all the way counterclockwise until it
stops. •
Release the shift lever and make sure it is fully seated
in the PARK gate.
• Look at the transmission gear position display and
verify that it indicates the PARK position.
• With brake pedal released, verify that the shift lever
will not move out of PARK.
REVERSE (R)
This range is for moving the vehicle backward. Shift into
REVERSE only after the vehicle has come to a complete
stop.
NEUTRAL (N)
Use this range when the vehicle is standing for prolonged
periods with the engine running. The engine may be
started in this range. Apply the parking brake and shift
the transmission into PARK if you must leave the vehicle.
236 STARTING AND OPERATING
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WARNING!
Do not coast in NEUTRAL and never turn off the
ignition to coast down a hill. These are unsafe
practices that limit your response to changing traffic
or road conditions. You might lose control of the
vehicle and have a collision.
CAUTION!
Towing the vehicle, coasting, or driving for any other
reason with the transmission in NEUTRAL can cause
severe transmission damage. Refer to “Recreational
Towing” in “Starting And Operating” and “Towing A
Disabled Vehicle” in “What To Do In Emergencies”
for further information.DRIVE (D)
This range should be used for most city and highway
driving. It provides the smoothest upshifts and down-
shifts, and the best fuel economy. The transmission
automatically upshifts through underdrive first, second,
and third gears, direct fourth gear and overdrive fifth and
sixth gears. The DRIVE position provides optimum driv-
ing characteristics under all normal operating conditions.
When frequent transmission shifting occurs (such as
when operating the vehicle under heavy loading condi-
tions, in hilly terrain, traveling into strong head winds, or
while towing heavy trailers), use the Electronic Range
Select (ERS) shift control (refer to “Electronic Range
Select (ERS) Operation” in this section for further infor-
mation) to select a lower gear range. Under these condi-
tions, using a lower gear range will improve performance
and extend transmission life by reducing excessive shift-
ing and heat buildup.
4
STARTING AND OPERATING 237
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If the transmission temperature exceeds normal operat-
ing limits, the powertrain controller will modify the
transmission shift schedule and expand the range of
torque converter clutch engagement. This is done to
prevent transmission damage due to overheating.
If the transmission becomes extremely hot or is in danger
of overheating, the “Transmission Temperature Warning
Light” may illuminate and the transmission may operate
differently until the transmission cools down.
NOTE:Use caution when operating a heavily loaded
vehicle at low speeds (such as towing a trailer up a steep
grade, or in stop-and-go traffic) during hot weather. In
these conditions, torque converter slip can impose a
significant additional heat load on the cooling system.
Downshifting the transmission to the lowest possible
gear (when climbing a grade), or shifting to NEUTRAL
(when stopped in heavy traffic) can help to reduce this
excess heat generation. During cold temperatures, transmission operation may
be modified depending on engine and transmission
temperature as well as vehicle speed. This feature im-
proves warm up time of the engine and transmission to
achieve maximum efficiency. Engagement of the torque
converter clutch is inhibited until the transmission fluid
is warm (refer to the “Note” under “Torque Converter
Clutch” in this section). On Pickup models with 68RFE
transmission, top overdrive gear is also inhibited until
the transmission fluid is warm, and during extremely
cold temperatures (-16°F [-27°C] or below), operation
may briefly be limited to first and direct gears only. On
trucks with AS69RC transmission, fifth and sixth gears
may be inhibited briefly on cold starts below 41°F (5°C),
and during very cold temperatures (-4°F [-20°C] or
below), operation may briefly be limited to third gear
only. During this condition, the ability of the vehicle to
238 STARTING AND OPERATING
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•The engine coolant has reached an adequate tempera-
ture.
• The vehicle speed is sufficiently high.
• The driver is not heavily pressing the accelerator.
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 switch to activate TOW/
HAUL mode. This will improve performance and reduce
the potential for transmission overheating or failure due
to excessive shifting. When operating in TOW/HAUL
mode, transmission upshifts are delayed, and the trans-
mission will automatically downshift (for engine brak-
ing) when the throttle is closed and/or during steady
braking maneuvers.
The “TOW/HAUL Indicator Light” will illuminate in the
instrument cluster to indicate that TOW/HAUL mode has
been activated. Pressing the switch a second time restores
normal operation. Normal operation is always the default
at engine start-up. If TOW/HAUL mode is desired, the
switch must be pressed each time the engine is started.
TOW/HAUL Switch
242 STARTING AND OPERATING
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WARNING!
Do not use the “TOW/HAUL” feature when driving
in icy or slippery conditions. The increased engine
braking could cause the rear wheels to slide, and the
vehicle to swing around with the possible loss of
vehicle control, which could cause an accident possi-
bly resulting in personal injury or death.
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 68RFE-
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 the
engine speed is higher when the torque converter 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 transmis-
sion 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 converter
will refill within five seconds after starting the engine.
4
STARTING AND OPERATING 243
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Truck models with manual transmission are equipped
with a clutch interlocking ignition system. The clutch
pedal must be fully pressed to start the vehicle.
Fully press the clutch pedal before shifting gears. As you
release the clutch pedal, lightly press the accelerator
pedal.
This transmission has a “creeper” first gear which should
be used to start from a standing position when carrying a
payload or towing a trailer. Damage to the clutch can result
from starting in second or third gear with a loaded vehicle.
An unloaded vehicle may be launched in second gear. Use
each gear in numerical order – do not skip a gear.
NOTE:When loaded, pulling a trailer or on a grade, the
truck should always start in first gear and not skip gears.
Recommended Vehicle Shift Speeds
To utilize your manual transmission efficiently for both
fuel economy and performance, it should be upshifted as
listed in recommended shift speed chart. Shift at the
vehicle speeds listed for acceleration. When heavily
loaded or pulling a trailer these recommended up-shift
speeds may not apply.
Maximum Recommended Up-Shift Speeds
Gear Selection 1 to 2 2 to 33 to 44 to 5 5 to 6
Maximum Speed 7 mph
(11 km/h) 15 mph
(24 km/h) 25 mph
(40 km/h) 40 mph
(64 km/h) 45 mph
(72 km/h)
4
STARTING AND OPERATING 245
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Mileage or time passed (which-ever comes first):
7,500
15,000
22,500
30,000
37,500
45,000
52,500
60,000
67,500
75,000
82,500
90,000
97,500
105,000 112,500
120,000
127,500
135,000
142,500
150,000
Or Months: 6 12 18 24 30 36 42 48 54 60 66 72 78 84 90 96 102 108 114 120
Or Kilometers:
12,000
24,000
36,000
48,000
60,000
72,000
84,000
96,000
108,000
120,000
132,000
144,000
156,000
168,000
180,000
192,000
204,000
216,000
228,000
240,000
Inspect the front and rear axle
surfaces. If gear oil leakage is
suspected, check the fluid level. If
using your vehicle for police, taxi,
fleet, off-road or frequent trailer
towing change the axle fluid. *
Inspect the transfer case fluid
(4x4), change for any of the fol-
lowing: police, taxi, fleet, or fre-
quent trailer towing. XXXX X
Change the transfer case fluid
(4x4). XX
328 MAINTENANCE SCHEDULE