2007 Ram 2500 (Diesel) Owner's Manual

When additional coolant is needed to maintain the
proper level, it should be added to the coolant bottle. Do
not overfill.
Points To Remember
NOTE:When the vehicle is stopped after a few miles (a
few kilometers) of operation, you may observe vapor
coming from the front of the engine compartment. This is
normally a result of moisture from rain, snow, or high
humidity accumulating on the radiator and being vapor-
ized when the thermostat opens, allowing hot coolant to
enter the radiator.
If an examination of your engine compartment shows no
evidence of radiator or hose leaks, the vehicle may be
safely driven. The vapor will soon dissipate.
•Do not overfill the coolant recovery bottle.
•Check coolant freeze point in the radiator and in the
coolant recovery bottle. If antifreeze needs to be
added, contents of coolant recovery bottle must also be
protected against freezing.
•If frequent coolant additions are required, or if the
level in the coolant recovery bottle does not drop when
the engine cools, the cooling system should be pres-
sure tested for leaks.
•Maintain coolant concentration at 50% HOAT engine
coolant (minimum) and distilled water for proper
corrosion protection of your engine which contains
aluminum components.
•Make sure that the radiator and coolant recovery
bottle overflow hoses are not kinked or obstructed.
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•Keep the front of the radiator clean. If your vehicle is
equipped with air conditioning, keep the front of the
condenser clean, also.
•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.
Fan
Inspection
Check the fan for cracks and bent or broken blades. If any
of these conditions exist, you must replace the fan. Make
sure it is securely mounted.
NOTE:This service procedure must be performed by a
trained service technician. Make arrangements with your
authorized Dodge Truck Dealer for this inspection.
Charge Air Cooler (Inter-Cooler)
The charge air cooler is positioned between the radiator
and the air conditioner condenser. Air enters the engine
through the air cleaner and passes through the turbo-
charger where it is pressurized. This pressurized air
rapidly reaches high temperature. The air is then directed
through a hose to the charge air cooler and through
another hose to the intake manifold of the engine. The air
entering the engine has been cooled by about 50 to 100
degrees Fahrenheit. This cooling process enables more
efficient burning of fuel resulting in fewer emissions.
To guarantee optimum performance of the system, keep
the surfaces of the charge air cooler, condenser and
radiator clean and free of debris. Periodically check the
hoses leading to and from the charge air cooler for cracks
or loose clamps resulting in loss of pressure and reduced
engine performance.
450 MAINTAINING YOUR VEHICLE

Hoses And Vacuum/Vapor Harnesses
Inspect surfaces of hoses and nylon tubing for evidence
of heat and mechanical damage. Hard or soft spots,
brittle rubber, cracking, tears, cuts, abrasions, and exces-
sive swelling indicate deterioration of the rubber.
Pay particular attention to those hoses nearest to high
heat sources such as the exhaust manifold. Inspect hose
routing to be sure hoses do not come in contact with any
heat source or moving component which may cause heat
damage or mechanical wear.
Insure nylon tubing in these areas has not melted or
collapsed.Inspect all hose connections such as clamps and cou-
plings to make sure they are secure and no leaks are
present.
Components should be replaced immediately if there is
any evidence of wear or damage that could cause failure.
Brake System
Power Disc Brakes (Front and Rear)
Disc brakes do not require adjustment; however, several
hard stops during the break-in period are recommended
to seat the linings and wear off any foreign material.
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Brake Master Cylinder
The fluid level of the master cylinder should be checked
when performing under the hood service, or immedi-
ately if the brake system warning lamp indicates system
failure.
The brake master cylinder has a translucent plastic
reservoir. On the outboard side of the reservoir, there is a“FULL” dot and an “ADD” dot. The fluid level must be
kept within these two dots. Do not add fluid above the
full mark because leakage may occur at the cap.
With disc brakes the fluid level can be expected to fall as
the brake linings wear. However, an unexpected drop in
fluid level may be caused by a leak and a system check
should be conducted.
Refer to Fluids, Lubricants and Genuine Parts for the
correct Fluid type.
WARNING!
Use of a brake fluid that may have a lower initial
boiling point, or unidentified as to specification, may
result in sudden brake failure during hard prolonged
braking. You could have an accident.
452 MAINTAINING YOUR VEHICLE

WARNING!
Overfilling the brake fluid reservoir can result in
spilling brake fluid on hot engine parts and the
brake fluid catching fire.
Use only brake fluid that has been in a tightly closed
container to avoid contamination from foreign matter or
moisture.
CAUTION!
Do not allow a petroleum-base fluid to contaminate
the brake fluid. Seal damage and loss of brake
performance may result.
Brake Hoses
Inspection should be performed whenever the brake
system is serviced or at intervals specified. Inspect hy-
draulic brake hoses for surface cracking, scuffing or worn
spots. If there is any evidence of cracking, scuffing, or
worn spots, the hose should be replaced immediately!
Eventual deterioration of the hose can take place with
possible burst failure.
Clutch Linkage
If the clutch pedal linkage begins to squeak or grunt, the
clutch pedal pivot bushings should be lubricated. Refer
to Fluids, Lubricants and Genuine Parts for the correct
lubricant type. Multipurpose Grease, NLGI Grade 2 E.P.
Clutch Hydraulic System
The clutch hydraulic system is a sealed maintenance-free
system. In the event of leakage or other malfunction, the
system must be replaced.
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Rear Axle And 4x4 Front Driving Axle Fluid Level
For Model 9.25 Front Axles and 10.5”/11.5” Rear Axles
refer to Fluids, Lubricants and Genuine Parts for the
correct lubricant type. For normal service, periodic fluid
level checks are not required. When the vehicle is ser-
viced for other reasons, the exterior surfaces of the axle
assembly should be inspected.
When checking the fluid level, the vehicle should be in a
level position. The fluid level should be 1/4” ± 1/4” (6.4
mm ± 6.4 mm) below the fill hole on the 9.25” Front Axle.
The fluid level should be 3/4” ± 1/4” (19 mm ± 6.4 mm)
below the fill hole on all 10.5” and 1/4” ± 1/4” (6.4 mm
± 6.4 mm) on 11.5” Rear Axles.
Drain And Refill
Vehicles operated in normal service do not have regularly
scheduled oil changes. If fluid has become contaminatedwith water or subjected to severe service, follow the
recommended change intervals in Maintenance Schedule
“B” in Section 8 of this manual.
Lubricant Selection
Refer to Fluids, Lubricants and Genuine Parts for the
correct lubricant type.
NOTE:The presence of water in the gear lubricant will
result in corrosion and possible failure of differential
components. Operation of the vehicle in water, as may be
encountered in some off-highway types of service, will
require draining and refilling the axle to avoid damage.
Limited-Slip Differentialsin vehicles equipped with
10.5”/11.5” AxlesDO NOT REQUIREany limited slip
oil additive (friction modifiers).
454 MAINTAINING YOUR VEHICLE

Transfer Case — If Equipped
Fluid Level Check
This fluid level can be checked by removing the filler
plug. The fluid level should be to the bottom edge of the
filler plug hole with the vehicle in a level position.
Lubricant Selection
Refer to Fluids, Lubricants and Genuine Parts for the
correct lubricant type.
Manual Transmission — If Equipped
Fluid Level Check
This fluid level can be checked by removing the filler
plug. If the level of the lubricant is more than 1/4” below
the bottom of the filler hole while the vehicle is on level
ground, enough lubricant should be added to bring the
level to the bottom of the filler hole.
Lubricant Selection for 6-Speed Manual
Transmission — If Equipped
If it becomes necessary to add fluid or change the fluid,
be sure to use the same lubricant or equivalent. Refer to
Fluids, Lubricants and Genuine Parts for the correct
lubricant type.
Automatic Transmission
Fluid Level Check
The fluid level should be checked when the engine is
fully warmed up and the fluid in the transmission is at
normal operating temperature. Operation of the trans-
mission with an improper fluid level will greatly reduce
the life of the transmission and of the fluid. Check the
fluid level whenever the vehicle is serviced.
MAINTAINING YOUR VEHICLE 455
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Procedure For Checking Fluid Level
To properly check the automatic transmission fluid level,
the following procedure must be used:
1. The vehicle must be on level ground.
2. The engine should be running at curb idle speed for a
minimum of 60 seconds.
3. Fully apply parking brake.
4. Place the gear selector briefly in each gear position
ending with the lever in N (Neutral).
5. Remove the dipstick and determine if the fluid is hot
or warm. Hot fluid is approximately 180°F (82°C) which
is the normal operating temperature after the vehicle has
been driven at least 15 miles. The fluid can not be
comfortably held between the finger tips. Warm is when
fluid is between 85° - 125°F (29° - 52°C).6. Wipe the dipstick clean and reinsert until seated.
Remove dipstick and note reading.
a. If the fluid is hot, the reading should be in the
crosshatched area marked “OK”.
b. If the fluid is warm, the reading should be between
the two holes. If the fluid level indicates low, add
sufficient fluid to bring to the proper level.
Fluid is added through the dipstick tube.
NOTE:To prevent dirt and water from entering the
transmission after checking or replenishing fluid, make
certain that the dipstick cap is properly seated.
456 MAINTAINING YOUR VEHICLE