2008 DODGE RAM 2500 GAS Owners Manual

When To Use ªTOW HAULº and ªO/D OFFº
Modes
When driving in hilly areas, towing a trailer, carrying a
heavy load, etc., and frequent transmission shifting oc-
curs, press the ªTOW HAUL O/D OFFº button once to
select TOW HAUL. This will improve performance andreduce the potential for transmission overheating or
failure due to excessive shifting. When operating in
ªTOW HAULº 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 are performed (for im-
proved braking) when driving conditions warrant. Press-
ing the ªTOW HAUL O/D OFFº button a second time to
select O/D OFF will disable 4th and 5th gear completely,
which should eliminate any excessive transmission shift-
ing.
The ªTOW HAULº or ªO/D OFFº light will illuminate in
the instrument cluster to indicate when the switch has
been activated. Pressing the switch a third time restores
normal operation. If the ªTOW HAULº or ªO/D OFFº
modes are desired, the button must be pressed each time
the engine is started.
Tow Haul O/D Off Switch
STARTING AND OPERATING 287
5

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
acceleration when the transmission downshifts to second
gear, the clutch automatically disengages.
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 the ªTOW HAUL O/D OFFº button, when the
transmission is sufficiently warm, 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 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 of shifting from PARK into
any other gear position.
MANUAL TRANSMISSION
WARNING!
You or others could be injured if you leave the
vehicle unattended without having the parking
brake fully applied. The parking brake should al-
ways be applied when the driver is not in the vehicle,
especially on an incline.
288 STARTING AND OPERATING

CAUTION!
Never drive with your foot resting on the clutch
pedal, or attempt to hold the vehicle on a hill with the
clutch pedal partially engaged, as this will cause
abnormal wear on the clutch.
NOTE:During cold weather, you may experience in-
creased effort in shifting until the transmission fluid
warms up. This is normal.
Shifting Ð 2500/3500 Models
Truck models with manual transmission are equipped
with a clutch interlocking ignition system. The clutch
pedal must be fully depressed to start the vehicle.
Shift Pattern
STARTING AND OPERATING 289
5

Fully depress the clutch pedal before shifting gears. As
you release the clutch pedal, lightly depress the accelera-
tor pedal.
2500 and 3500 models are equipped with the G56 manual
transmission. This transmission has a ªcreeperº 1st 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 2nd or 3rd gear with
a loaded vehicle. An unloaded vehicle may be launched
in 2nd gear. Use each gear in numerical order ± do not
skip a gear.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
En-
gineModel L to 2 2 to 3 3 to 4 4 to 5 5 to 6
5.7L2500/
350015
mph
(24
km/h)25
mph
(40
km/h)40
mph
(64
km/h)45
mph
(72
km/h)50
mph
(81
km/h)
290 STARTING AND OPERATING

Shifting Ð 1500 Vehicles
1500 models are equipped with a G238 manual transmis-
sion. This transmission has a clutch interlocking ignition
system. The clutch pedal must be fully depressed to start
the vehicle.Fully depress the clutch pedal before shifting gears. As
you release the clutch pedal, lightly depress the accelera-
tor pedal.
You should always use 1st gear when starting from a
standing position.
Recommended 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.
Shift Pattern (1500 Models)
STARTING AND OPERATING 291
5

Higher upshift speeds may be used to obtain a desired
acceleration rate.
6 Speed Manual Transmission Shift Speed in mph
(km/h)
En-
gineModel AxleAccel-
eration
Rate1to
22to
33to
44to
55to
6
3.7L ALL ALLACCEL
&
CRUISE15
(24)
10
(16)24
(39)
19
(31)34
(55)
27
(44)47
(76)
37
(60)56
(90)
41
(66)
4.7L All ALLACCEL
&
CRUISE15
(24)25
(40)40
(65)45
(72)50
(81)
Downshifting ± All Manual Transmissions
Moving from a high gear down to a lower gear is
recommended to preserve brakes when driving down
steep hills. In addition, downshifting at the right time
provides better acceleration when you desire to resume
speed. Downshift progressively. Do not skip gears to
avoid overspeeding the engine and clutch.
WARNING!
Do not downshift for additional engine braking on a
slippery surface. The drive wheels could lose their
grip and the vehicle could skid.
292 STARTING AND OPERATING

CAUTION!
When descending a hill, be very careful to downshift
one gear at a time to prevent overspeeding the engine
which can cause valve damage, and/or clutch disc
damage even if the clutch pedal is depressed.
Maximum Recommended Downshift Speeds
CAUTION!
Failure to follow the recommended downshifting
speeds may cause the engine to overspeed and/or
damage the clutch disc even if the clutch pedal is
depressed.Maximum Recommended Downshifting Speeds
Gear
Selec-
tion6to5 5to4 4to3 3to2 2to1
Maxi-
mum
Speed85 mph
(135
km/h)75 mph
(120
km/h)55 mph
(88
km/h)35 mph
(56
km/h)20 mph
(32
km/h)
Reverse Shifting
To shift into REVERSE (R), bring the vehicle to a com-
plete stop. Depress the clutch and pause briefly to allow
the gear train to stop rotating. Beginning from the
NEUTRAL (N) position, move the shift lever in one quick
smooth motion straight across and into the REVERSE (R)
area (the driver will feel a firm ªclickº as the shifter
passes the ªknock-overº). Complete the shift by pulling
the shift lever into REVERSE (R).
STARTING AND OPERATING 293
5

The ªknock-overº prevents the driver from accidentally
entering the REVERSE (R) shift area and warns the driver
that they are about to shift the transmission into RE-
VERSE (R). Due to this feature, a slow shift to REVERSE
(R) can be perceived as a high shift effort.
On 2500/3500 models, when shifting out of reverse bring
the vehicle to a complete stop and depress the clutch.
Shifting out of reverse prior to a complete stop may cause
high shift effort.
FOUR-WHEEL DRIVE OPERATION Ð 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.
Manually Shifted Transfer Case Operating
Information/Precautions
The transfer case provides 4 mode positions-2(rear)-
wheel drive high range, 4-wheel drive high range, neu-
tral, and 4-wheel drive low range.
This transfer case is intended to be driven in the 2-wheel
drive position (2H) for normal street and highway con-
ditions such as dry, hard surfaced roads.
When additional traction is required, the transfer case 4H
and 4L positions can be used to lock the front and rear
driveshafts 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.
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 damage to the driveline components.
294 STARTING AND OPERATING