fuel pressure RAM CHASSIS CAB 2007 Owners Manual

CAUTION!• During the first 500 miles (805 km) your new
vehicle is driven, do not tow a trailer. Doing so
may damage your axles, driveline and vehicle.
• Limit your speed to 50 mph (80 km/h) during the
first 500 miles (805 km) of towing.
6.7L Diesel Engine
Your Cummins 24 Valve Turbo Diesel engine does not
require a break-in period due to its construction. Normal
operation is allowed, provided the following recommen-
dations are followed:
NOTE: Light duty operation such as light trailer towing
or no load operation, will extend the time before the
engine is at full efficiency and may effect the performance
of the vehicle aftertreatment (exhaust) system. Reduced
fuel economy and power may be seen at this time. • Warm up the engine before placing it under load.
• Do not operate the engine at idle for prolonged
periods.
• Use the appropriate transmission gear to prevent
engine lugging.
• Observe vehicle oil pressure and temperature indica-
tors.
• Check the coolant and oil levels frequently.
• Vary throttle position at highway speeds when carry-
ing or towing significant weight.
Because of the construction of the Cummins Diesel
engine, engine run-in is enhanced by loaded operating
conditions which allow the engine parts to achieve final
finish and fit during the first 6,000 miles (10 000 km). THINGS TO KNOW BEFORE STARTING YOUR VEHICLE 73
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INSTRUMENT CLUSTER DESCRIPTION
1. Check Gages
This light illuminates when the Voltmeter, Engine
Oil Pressure or Engine Coolant Temperature
gages indicate a reading either too high or too low.
Examine the gages carefully, and follow the instructions
above for each indicated problem.
NOTE: When the ignition switch is turned to OFF, the
Fuel Gage, Voltmeter, Oil Pressure and Engine Coolant
Temperature gages may not show accurate readings.
When the engine is not running, turn the ignition switch
to ON to obtain accurate readings.
2. Voltmeter
When the engine is running, the gauge indicates
the electrical system voltage. The pointer should
stay within the normal range if the battery is charged. If the pointer moves to either extreme left or right and
remains there during normal driving, the electrical sys-
tem should be serviced.
NOTE: If the gauge pointer moves to either extreme of
the gauge, the “Check Gages” indicator will illuminate
and a single chime will sound.
NOTE:
• The voltmeter may show a gauge fluctuation if certain
engine temperatures are below 66°F (19°C). This cy-
cling operation is caused by the post-heat cycle of the
intake manifold heater system. The number of cycles
and the length of the cycling operation is controlled by
the engine control module, this time will not exceed
150 seconds. The needle should then stabilize at the
approximate operation point.
• The cycling action will cause temporary dimming of
the headlamps, interior lamps, and also a noticeable
reduction in blower motor speed.172 UNDERSTANDING YOUR INSTRUMENT PANEL

a manual transmission. Models with manual transmis-
sion are equipped with a clutch interlocking cranking
system. The clutch must be fully depressed to start the
vehicle.
3. Turn the ignition key to the ON position and look at
the instrument panel cluster lamps.
CAUTION!If WATER IN FUEL indicator light remains on DO
NOT START engine before you drain water from the
fuel filter to avoid engine damage. See Section 7 —
Maintaining Your Vehicle, for water drain proce-
dures.
4. Turn the ignition key to START and crank the engine.
Do not press the accelerator during starting. CAUTION!Do not crank engine for more than 15 seconds at a
time as starter motor damage may result. Turn key to
OFF and wait at least two minutes before trying
again.
5. When the engine starts, release the key.
6. Check to see that there is oil pressure.
7. Release the parking brake.
Starting Procedure — Engine Manifold Air
Temperature Below 66°F (19°C)
NOTE: The temperature displayed on the overhead
console (if equipped) does not necessarily reflect the
engine manifold air temperature. When certain engine
temperatures fall below 66°F (19°C) the lamp will remain
on indicating the intake manifold heater system is active. STARTING AND OPERATING 253
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NOTE: When a diesel engine is allowed to run out of
fuel or the fuel gels at low temperatures, air is pulled into
the fuel system.
You may try priming as described below.
1. Add a substantial quantity of fuel to the tank (5 to 10
gallons) or eliminate the gelled fuel condition.
2. Crank the engine for 1 to 2 seconds. If the engine does
not start, then release the key or starter button back to the
RUN position (do not turn the key back to the OFF
position). The electric fuel transfer pump will continue to
run and purge air from the system for about 20 seconds.
After 20 seconds, attempt to start the engine again.
3. Start the engine using the Normal Starting Procedure.
4. Repeat the procedure if the engine does not start. WARNING!Do not open the high pressure fuel system when
cranking the engine or with the engine running.
Engine operation causes high fuel pressure. High
pressure fuel spray can cause serious injury or death.
NOTE: The engine may run rough until the air is forced
from all the fuel lines.256 STARTING AND OPERATING

Starting Fluids
WARNING!STARTING FLUIDS or flammable liquids are
NEVER TO BE USED in the Cummins Diesel (see
Warning label). Never pour diesel fuel, flammable
liquid, starting fluids (ether) into the air cleaner
canister, air intake piping, or turbocharger inlet in an
attempt to start the vehicle. This could result in a
flash fire and explosion causing serious personal
injury and engine damage.
The engine is equipped with an automatic electric air
preheating system. If the instructions in this manual are
followed, the engine should start in all conditions. WARNING!Do not leave children or animals inside parked
vehicles in hot weather. Interior heat build up may
cause serious injury or death.
NORMAL OPERATION – DIESEL ENGINE
Observe the following when the engine is operating.
• All message center lights are off.
• Check Engine Lamp is off.
• Engine Oil Pressure is above 10 psi (69 kPa) at idle.
• Low Oil Pressure light is off.
• Voltmeter Operation:
• The voltmeter may show a gauge fluctuation if
certain engine temperatures are below 66°F (19°C).
This cycling operation is caused by the post-heat STARTING AND OPERATING 257
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Winter Front Usage
If a winter front or cold weather cover is to be used, a
percentage of the total grille opening area must be left
uncovered to provide sufficient air flow to the charge air
cooler and automatic transmission oil cooler. The per-
centage of opening must be increased with the increasing
ambient air temperature and/or engine load. If the
cooling fan can be heard cycling frequently, increase the
size of the opening in the winter front. A suitable cold
weather cover is available from your Mopar  dealer.
Battery Blanket Usage
A battery loses 60% of its cranking power as the battery
temperature decreases to 0°F (-18°). For the same de-
crease in temperature, the engine requires twice as much
power to crank at the same RPM. The use of 120 VAC
powered battery blankets will greatly increase starting
capability at low temperatures. Suitable battery blankets
are available from your authorized Mopar  dealer. Arctic Operation
Where there are no provisions to keep the engine warm
when it is operating in ambient temperatures consistently
below (-10°F/-23°C), use 5W-40 synthetic engine oil and
fuel that meets the requirements in Section 7, “Mainte-
nance Procedures,” Engine Oil Selection.
Engine Warm-Up
Avoid full throttle operation when the engine is cold.
When starting a cold engine, bring the engine up to
operating speed slowly to allow the oil pressure to
stabilize as the engine warms up.
NOTE: High-speed, no-load running of a cold engine
can result in excessive white smoke and poor engine
performance. No-load engine speeds should be kept
under 1,200 rpm during the warm-up period, especially
in cold ambient temperature conditions.260 STARTING AND OPERATING

• Up Steep Hills —
select a lower transmission gear, but try and keep the
torque converter clutch engaged.
• Air Conditioning —
turn it off temporarily.
Do Not Operate The Engine With Low Oil
Pressure
When the engine is at normal operating temperature, the
minimum oil pressures required are:
Idle 700 to 800 RPM ............... 10psi(69kPa)
Full speed and load .............. 30psi (207 kPa)
CAUTION!If oil pressure falls to less than normal readings, shut
the engine off immediately. Failure to do so could
result in immediate and severe engine damage. Do Not Operate The Engine With Failed Parts
Practically all failures give some warning before the parts
fail. Be on the alert for changes in performance, sounds,
and visual evidence that the engine requires service.
Some important clues are:
• engine misfiring or vibrating severely
• sudden loss of power
• unusual engine noises
• fuel, oil or coolant leaks
• sudden change, outside the normal operating range, in
the engine operating temperature
• excessive smoke
• oil pressure drop264 STARTING AND OPERATING

Manual Transmission — 6 Speed (G56)
Your vehicle may be equipped with the G56 manual
transmission. This transmission has a “creeper” 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.
For most city driving you may find it easier to use only
1st through 5th gear ranges. For steady highway driving
with light accelerations, 6th gear is recommended. To
shift into 5th gear, move the shift lever to the right
beyond the spring pressure point and push it forward.
When shifting from 5th to 4th gear, pull the lever down
toward you in one motion. Do not pull the lever sharply left as you may shift accidentally into 2nd gear and
damage the transmission.
To shift into Reverse, come to a complete stop. Depress
the clutch and pause briefly to allow the gear train to
stop. Reverse has a “crash-through” lockout feature.
Move the shift lever from the Neutral position straight
across, in one swift motion, and down into Reverse.
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. Earlier upshifts
during cruise conditions (steady speeds) will result in
increased fuel economy, and may be used as indicated.280 STARTING AND OPERATING

2. Economy—
Improper inflation pressures can cause uneven wear
patterns to develop across the tire tread. These abnormal
wear patterns will reduce tread life resulting in a need for
earlier tire replacement. Under inflation, also increases
tire rolling resistance and results in higher fuel consump-
tion.
3. Ride Comfort and Vehicle Stability—
Proper tire inflation contributes to a comfortable ride.
Over inflation produces a jarring and uncomfortable ride.
Tire Inflation Pressures
The proper cold tire inflation pressure is listed either on
the face of the driver’s door or on the driver’s side “B”
pillar.
Some vehicles may have Supplemental Tire Pressure
Information for vehicle loads that are less than the maximum loaded vehicle condition. These pressure con-
ditions will be found in the “Supplemental Tire Pressure
Information” section of this manual.
The pressure should be checked and adjusted as well as
inspecting for signs of tire wear or visible damage at least
once a month. Use a good quality pocket-type gauge to Tire Placard Location STARTING AND OPERATING 315
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You may try priming as described below. However, if the
engine will not start, refer to the fuel priming procedure
in the Service Manual or have the vehicle towed to an
authorized Dodge dealer.
WARNING!Do not open the high pressure fuel system with the
engine running. Engine operation causes high fuel
pressure. High pressure fuel spray can cause serious
injury or death.
Priming if the engine has run out of fuel
1. Add a substantial quantity of fuel to the tank 5 to 10
gallons (19 to 38L).
2. Crank the engine for 1 to 2 seconds. If the engine does
not start, then release the key or starter button back to the
RUN position (do not turn the key back to the OFF position). The electric fuel transfer pump will continue to
run and purge air from the system for about 20 seconds.
After 20 seconds, attempt to start the engine again.
3. Start the engine using the Normal Starting Procedure.
4. Repeat the procedure if the engine does not start.
CAUTION!Do not engage the starter motor for more than 15
seconds at a time. Allow two minutes between the
cranking intervals.
NOTE: The engine may run rough until the air is forced
from all the fuel lines. STARTING AND OPERATING 337
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