2007 DODGE RAM 2500 DIESEL tire type

The 4-wheel-drive light (4WD), located in the instrument
cluster, alerts the driver that the vehicle is in 4-wheel
drive and that the front and rear driveshafts are locked
together. This light illuminates when the transfer case is
shifted to either the 4H or 4L positions. There is no light
for the 2H or N (Neutral) positions.
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).
Proper operation of 4-wheel-drive vehicles depends on
tires of equal size, type and circumference on each wheel.
Any difference will adversely affect shifting and can
cause damage to the transfer case. NOTE:
Do not attempt to make a shift while only the
front or rear wheels are spinning. The transfer case is not
equipped with a synchronizer and therefore the front and
rear driveshaft speeds must be equal for the shift to take
place. Shifting while only the front or rear wheels are
spinning can cause damage to the transfer case.
Because 4-wheel drive provides improved traction, there
is a tendency to exceed safe turning and stopping speeds.
Do not go faster than road conditions permit.
NOTE: Delayed shifts out of four-wheel drive may be
experienced due to uneven tire wear, low or uneven tire
pressures, excessive vehicle loading, or cold tempera-
tures.
STARTING AND OPERATING 277
5

WARNING!
Always engage the parking brake when powering
down the vehicle if the Service 4WDlight 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. The transfer case is not
equipped with a synchronizer and therefore the front and
rear driveshaft speeds must be equal for the shift to take
place. Shifting while only the front or rear wheels are
spinning can cause damage to the transfer case. When operating your vehicle in 4LO, the engine speed is
approximately three times that of the 2WD or 4HI
positions at a given road speed. Take care not to over-
speed the engine and do not exceed 25 mph (40 km/h).
Proper operation of 4 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
transfer case.
Because 4 wheel drive provides improved traction, there
is a tendency to exceed safe turning and stopping speeds.
Do not go faster than road conditions permit.
STARTING AND OPERATING 283
5

DRIVING OFF-ROAD
Care should be taken when attempting to climb steep
hills or driving diagonally across a hill or slope. If natural
obstacles force you to travel diagonally up or down a hill,
choose a mild angle and keep as little side tilt as possible.
Keep the vehicle moving and make turns slowly and
cautiously.
If you must back down a hill, back straight down using
REVERSE gear. Never back down in NEUTRAL, or
diagonally across the hill.
When driving over sand, mud, and other soft terrain,
shift to low gear and drive steadily. Apply the accelerator
slowly to avoid spinning the wheels.
DO NOT REDUCE the tire pressures for this type of
driving. NOTE:
After off-road usage, particularly in sand or
mud, inspect the underside of the vehicle for accumu-
lated dirt at the propeller shaft, axles, U-joints, brake
rotors and calipers.
Use a hose to clean off any accumulation of dirt or mud.
Check the exhaust system and all exposed components
for any sign of damage.
If you experience unusual vibration after driving in mud,
slush or similar conditions, check the wheels for im-
pacted material. Impacted foreign material can cause a
wheel imbalance. Removing the foreign material from
the wheels will correct the situation.
STARTING AND OPERATING 289
5

2. Economy—
Improper inflation pressures can cause uneven wear pat-
terns 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 consumption.
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
check tire pressure. Do not make a visual judgement
when determining proper inflation. Radial tires may look
properly inflated even when they are under inflated.
Tire Placard Location
STARTING AND OPERATING 305
5

loading may be required for high-speed vehicle opera-
tion. Refer to original equipment or an authorized tire
dealer for recommended safe operating speeds, loading
and cold tire inflation pressures.
WARNING!
High speed driving with your vehicle under maxi-
mum load is dangerous. The added strain on your
tires could cause them to fail. You could have a
serious accident. Don’t drive a vehicle loaded to the
maximum capacity at continuous speeds above 75
mph (120 km/h).
Radial-Ply Tires
WARNING!
Combining radial ply tires with other types of tires
on your vehicle will cause your vehicle to handle
poorly. The instability could cause an accident. Al-
ways use radial ply tires in sets of four (or 6, in case
of trucks with dual rear wheels). Never combine
them with other types of tires.
Cuts and punctures in radial tires are repairable only in
the tread area because of sidewall flexing. Consult your
authorized tire dealer for radial tire repairs.
STARTING AND OPERATING 307
5

Improper alignment will not cause vehicle vibration.
Vibration may be a result of tire and wheel out-of-
balance. Proper balancing will reduce vibration and
avoid tire cupping and spotty wear.
SUPPLEMENTAL TIRE PRESSURE INFORMATION
– IF EQUIPPED
A light load vehicle condition is defined as two passen-
gers {150 lbs (68 kg) each} plus 200 lbs (91kg) of cargo.
Cold tire inflation pressures for a lightly loaded vehicle
will be found on the face of the driver’s door.
TIRE CHAINS
Use “Class U” chains on 2500/3500 Ram Trucks, or other
traction aids that meet SAE Type “U” specifications.
NOTE: Chains must be the proper size for the vehicle,
as recommended by the chain manufacturer.
CAUTION!
To avoid damage to your vehicle, tires or chains, observe the
following precautions:
•Because of limited chain clearance between tires and other
suspension components, it is important that only chains in
good condition are used. Broken chains can cause serious
vehicle damage. Stop the vehicle immediately if noise
occurs that could suggest chain breakage. Remove the
damaged parts of the chain before further use.
•Install chains as tightly as possible and then retighten after
driving about 1/2 mile (0.8 km).
•Do not exceed 45 mph (72 km/h).
•Drive cautiously and avoid severe turns and large bumps,
especially with a loaded vehicle.
•Do not install tire chains on front wheels of 4x2 vehicles.
•Do not drive for a prolonged period on dry pavement.
•Observe the tire chain manufacturer’s instructions on
method of installation, operating speed, and conditions for
usage. Always use the lower suggested operating speed of
the chain manufacturer if different than the speed recom-
mended by the manufacturer.
STARTING AND OPERATING 313
5

SNOW TIRES
Snow tires should be of the same size and type construc-
tion as the front tires. Consult the manufacturer of the
snow tire to determine any maximum vehicle speed
requirement associated with the tire. These tires should
always be operated at the vehicle maximum capacity
inflation pressures under any load condition.
While studded tires improve performance on ice, skid
and traction capability on wet or dry surfaces may be
poorer than that of non-studded tires. Some states pro-
hibit studded tires; therefore, local laws should be
checked before using these tire types.
TIRE ROTATION RECOMMENDATIONS
Tires on the front and rear axles of vehicles operate at
different loads and perform different steering, driving,
and braking functions. For these reasons, they wear at
unequal rates, and develop irregular wear patterns.
These effects can be reduced by timely rotation of tires.
The benefits of rotation are especially worthwhile with
aggressive tread designs such as those on On/Off Road
type tires. Rotation will increase tread life, help to main-
tain mud, snow, and wet traction levels, and contribute to
a smooth, quiet ride.
Follow the recommended tire rotation frequency for your
type of driving found in the “Maintenance Schedules”
Section of this manual. More frequent rotation is permis-
sible if desired. The reasons for any rapid or unusual
wear should be corrected prior to rotation being per-
formed.
STARTING AND OPERATING 315
5

NOTE:On Canadian vehicles only, if your Ram truck is
equipped with All-Season type tires on the front and
ON/OFF Road type tires mounted on the rear, do not use
a front to back rotation pattern. Instead, rotate your tires
side to side at the recommended intervals.
Dual Rear Wheels
The tires used on dual wheel assemblies should be
matched for wear to prevent overloading one tire in a set.
To check if tires are even, lay a straight edge across all
four tires. The straight edge should touch all the tires.
316 STARTING AND OPERATING