trailer DODGE RAM 2001 Service Repair Manual

DESCRIPTION
A multi-purpose, hypoid gear lubricant which con-
forms to the following specifications should be used.
Mopar Hypoid Gear Lubricant conforms to all of
these specifications.
SAE ratings also apply to multiple grade gear
lubricants. In addition, API classification defines the
lubricants usage.
FRONT AXLE
²The lubricant should have MIL-L-2105C and
API GL 5 quality specifications.
²Lubricant is SAE 75W-140 SYNTHETIC gear
lubricant.
REAR AXLE
²The lubricant should have MIL-L-2105C and
API GL 5 quality specifications.
²Lubricant is a thermally stable SAE 80W-90
gear lubricant.
²Lubricant for axles intended for heavy-duty or
trailer tow use is SAE 75W-140 SYNTHETIC gear
lubricant.
NOTE: Trac-lokYand Vari-lokYequipped axles
require a friction modifier be added to the lubricant.
CAUTION: If axle is submerged in water, lubricant
must be replaced immediately to avoid possible
premature axle failure.
DESCRIPTION - TRANSFER CASE FLUID
Recommended lubricant for the NV231 and NV241
transfer case is MopartATF +4, (MS 9602) Auto-
matic Transmission Fluid.
DESCRIPTION - AUTOMATIC TRANSMISSION
FLUID
NOTE: Refer to the maintenance schedules in this
group for the recommended maintenance (fluid/filter
change) intervals for this transmission.
NOTE: Refer to Service Procedures in this group for
fluid level checking procedures.
MopartATF +4, type 9602, Automatic Transmis-
sion Fluid is the recommended fluid for Daimler-
Chrysler automatic transmissions.
Dexron II fluid IS NOT recommended. Clutch
chatter can result from the use of improper
fluid.MopartATF +4, type 9602, Automatic Transmis-
sion Fluid when new is red in color. The ATF is dyed
red so it can be identified from other fluids used in
the vehicle such as engine oil or antifreeze. The red
color is not permanent and is not an indicator of fluid
condition. As the vehicle is driven, the ATF will begin
to look darker in color and may eventually become
brown.This is normal.A dark brown/black fluid
accompanied with a burnt odor and/or deterioration
in shift quality may indicate fluid deterioration or
transmission component failure.
FLUID ADDITIVES
DaimlerChrysler strongly recommends against the
addition of any fluids to the transmission, other than
those automatic transmission fluids listed above.
Exceptions to this policy are the use of special dyes
to aid in detecting fluid leaks.
Various ªspecialº additives and supplements exist
that claim to improve shift feel and/or quality. These
additives and others also claim to improve converter
clutch operation and inhibit overheating, oxidation,
varnish, and sludge. These claims have not been sup-
ported to the satisfaction of DaimlerChrysler and
these additivesmust not be used.The use of trans-
mission ªsealersº should also be avoided, since they
may adversely affect the integrity of transmission
seals.
OPERATION - AUTOMATIC TRANSMISSION
FLUID
The automatic transmission fluid is selected based
upon several qualities. The fluid must provide a high
level of protection for the internal components by
providing a lubricating film between adjacent metal
components. The fluid must also be thermally stable
so that it can maintain a consistent viscosity through
a large temperature range. If the viscosity stays con-
stant through the temperature range of operation,
transmission operation and shift feel will remain con-
sistent. Transmission fluid must also be a good con-
ductor of heat. The fluid must absorb heat from the
internal transmission components and transfer that
heat to the transmission case.
BR/BELUBRICATION & MAINTENANCE 0 - 5
FLUID TYPES (Continued)

105,000 Miles (168 000 km) or at 84 months
²Inspect auto tension drive belt and replace if
required.**
²Change engine oil.
²Replace engine oil filter.
²Inspect engine coolant level, hoses, and clamps.
²Inspect brake hoses.
²Lubricate the steering linkages.
²Check manual transmission fluid level.
²Inspect exhaust system.
112,500 Miles (180 000 km) or at 90 months
²Change engine oil.
²Replace engine oil filter.
²Inspect engine coolant level, hoses, and clamps.
²Flush and replace engine coolant if it has been
30,000 miles (48 000 km) or 24 months since last
change.
²Inspect brake hoses.
²Inspect brake linings.
²Inspect front wheel bearings. Clean and repack,
if required (4x2).
²Lubricate the steering linkages.
²Lubricate non permanently sealed ball joints.
²Check manual transmission fluid level.
²Drain and refill transfer case fluid.
²Inspect exhaust system.
120,000 Miles (192 000 km) or at 96 months
²Replace engine air cleaner element.
²Replace ignition cables.
²Check PCV valve and replace as neces-
sary.*
²Replace spark plugs.
²Inspect auto tension drive belt and replace if
required.**
²Change engine oil.
²Replace engine oil filter.
²Inspect engine coolant level, hoses, and clamps.
²Inspect brake hoses.
²Lubricate the steering linkages.
²Check manual transmission fluid level.
²Inspect exhaust system.
*This maintenance is recommended by Daimler-
Chrysler to the customer but it is not required to
maintain warranty on the PCV valve.
**This maintenance is not required if the belt was
previously replaced.
LIGHT DUTY SCHEDULE ªBº
Follow this schedule if the vehicle is usually oper-
ated under one or more of the following conditions.
²Frequent short trips of less than 5 miles.
²Frequent driving in dusty conditions.
²Trailer towing.
²Frequent long periods of engine idling.²More than 50 percent of the driving is at sus-
tained high speeds during hot weather, above 90ÉF
(32ÉC).
²Frequent stop and go driving.
²Day and night temperatures are below freezing.
²Taxi, police or delivery service (commercial ser-
vice).
²Off-road or desert operation.
3,000 Miles (5 000 km)
²Change engine oil.
²Replace engine oil filter.
²Inspect engine coolant level, hoses, and clamps.
²Inspect brake hoses.
²Lubricate the steering linkages.
²Check manual transmission fluid level.
²Inspect exhaust system.
6,000 Miles (10 000 km)
²Change engine oil.
²Replace engine oil filter.
²Inspect engine coolant level, hoses, and clamps.
²Inspect brake hoses.
²Lubricate the steering linkages.
²Check manual transmission fluid level.
²Inspect exhaust system.
9,000 Miles (14 000 km)
²Change engine oil.
²Replace engine oil filter.
²Inspect engine coolant level, hoses, and clamps.
²Inspect brake hoses.
²Lubricate the steering linkages.
²Check manual transmission fluid level.
²Inspect exhaust system.
12,000 Miles (19 000 km)
²Change engine oil.
²Replace engine oil filter.
²Inspect engine coolant level, hoses, and clamps.
²Inspect brake hoses.
²Inspect brake linings.
²Lubricate the steering linkages.
²Check manual transmission fluid level.
²Change rear axle fluid.
²Change front axle fluid (4x4).
²Inspect exhaust system.
15,000 Miles (24 000 km)
²Inspect engine air cleaner element, replace
as necessary.
²Change engine oil.
²Replace engine oil filter.
²Inspect engine coolant level, hoses, and clamps.
²Inspect brake hoses.
²Lubricate the steering linkages.
²Check manual transmission fluid level.
BR/BELUBRICATION & MAINTENANCE 0 - 9
MAINTENANCE SCHEDULES (Continued)

²Inspect front wheel bearings. Clean and repack,
if required (4x2).
114,000 Miles (183 000 km) or at 116 months
²Replace engine oil and filter.
120,000 Miles (192 000 km) or at 124 months
²Replace engine oil and filter.
²Replace engine air cleaner element.
²Replace ignition cables.
²Replace spark plugs.
²Drain and refill automatic transmission fluid.
Replace filter and adjust bands.
MEDIUM DUTY SCHEDULE ªBº
Follow this schedule if the vehicle usually operates
under one or more of the following conditions.
²Frequent short trips less than 5 miles (8 km).
²Frequent driving in dusty conditions
²Frequent trailer towing
²Extensive idling
²Move than 50% of the driving is at sustained
high speeds during hot weather, above 90É F (32É C)
3,000 Miles (5 000 km)
²Replace engine oil and filter.
6,000 Miles (10 000 km)
²Replace engine oil and filter.
9,000 Miles (14 000 km)
²Replace engine oil and filter.
12,000 Miles (19 000 km)
²Replace engine oil and filter.
²Drain and refill automatic transmission fluid.
Replace filter and adjust bands.³
²Change rear axle fluid.
²Change front axle fluid (4x4).
²Inspect brake linings.
15,000 Miles (24 000 km)
²Replace engine oil and filter.
²Inspect engine air cleaner element, replace
as necessary.
18,000 Miles (29 000 km)
²Replace engine oil and filter.
21,000 Miles (29 000 km)
²Replace engine oil and filter.
24,000 Miles (38 000 km)
²Replace engine oil and filter.
²Drain and refill automatic transmission fluid.
Replace filter and adjust bands.²Inspect front wheel bearings. Clean and repack,
if required (4x2).
²Change rear axle fluid.
²Change front axle fluid (4x4).
²Inspect brake linings.
27,000 Miles (43 000 km)
²Replace engine oil and filter.
30,000 Miles (48 000 km)
²Replace engine oil and filter.
²Replace engine air cleaner element.
²Replace spark plugs.
33,000 Miles (53 000 km)
²Replace engine oil and filter.
36,000 Miles (58 000 km)
²Replace engine oil and filter.
²Drain and refill automatic transmission fluid.
Replace filter and adjust bands.³
²Drain and refill transfer case fluid.
²Change rear axle fluid.
²Change front axle fluid (4x4).
²Inspect brake linings.
²Inspect front wheel bearings. Clean and repack,
if required (4x2).
39,000 Miles (62 000 km)
²Replace engine oil and filter.
42,000 Miles (67 000 km)
²Replace engine oil and filter.
45,000 Miles (72 000 km)
²Replace engine oil and filter.
²Inspect engine air cleaner element, replace
as necessary.
48,000 Miles (77 000 km)
²Replace engine oil and filter.
²Drain and refill automatic transmission fluid.
Replace filter and adjust bands.
²Change rear axle fluid.
²Change front axle fluid (4x4).
²Inspect brake linings.
²Flush and replace engine coolant.
51,000 Miles (82 000 km)
²Replace engine oil and filter.
54,000 Miles (86 000 km)
²Replace engine oil and filter.
²Inspect front wheel bearings. Clean and repack,
if required (4x2).
BR/BELUBRICATION & MAINTENANCE 0 - 15
MAINTENANCE SCHEDULES (Continued)

²Inspect brake linings.
³Off-the-highway operation, trailer towing snow
plowing, prolonged operation with heavy loading,
especially in hot weather require the more frequent
transmission service indicated with an ³ in Schedule
ªBº. Perform these services if the vehicle is usually
operated under these conditions.
Inspection and service should also be performed
anytime a malfunction is observed or suspected.
DESCRIPTION - HEAVY DUTY ENGINE
(FEDERAL ONLY ± 2500 8.0L HD AND 3500
5.9L& 8.0L MODELS) MAINTENANCE
SCHEDULES
There are two maintenance schedules that show
proper service based on the conditions that the vehi-
cle is subjected to. Use the schedule that best
describes these conditions.
ScheduleªAº, lists all the scheduled maintenance
to be performed under normal operating conditions
for Heavy Duty vehicles.
ScheduleªBº, lists maintenance recommended for
Heavy Duty vehicles operated under the conditions
listed at the beginning of that schedule.
²Where time and mileage are listed, follow the
interval that occurs first.
At Each Stop For Fuel
²Check engine oil level, add as required.
²Check windshield washer solvent and add if
required.
²Clean windshield and wiper blades as required.
Once A Month
²Check tire pressure and look for unusual wear
or damage.
²Inspect battery and clean and tighten terminals
as required.
²Check fluid levels of coolant reservoir, power
steering and transmission and add as needed.
²Check all lights and all other electrical items for
correct operation.
²Inspect and clean wiper blades. Replace if
required.
At Each Oil Change
²Inspect exhaust system.
²Inspect brake hoses.
²Adjust rear brakes.
²Rotate the tires at each oil change interval
shown on schedule ªAº (6,000 Miles) or every other
interval shown on schedule ªBº (6,000 Miles).
²Check engine coolant level, hoses, and clamps.
²Lubricate steering linkage.
EMISSION CONTROL SYSTEM MAINTENANCE
The scheduled emission maintenance listed inbold
typeon the Maintenance Schedules, must be done at
the mileage specified to assure the continued proper
functioning of the emission control system. These,
and all other maintenance services included in this
manual, should be done to provide the best vehicle
performance and reliability. More frequent mainte-
nance may be needed for vehicles in severe operating
conditions such as dusty areas and very short trip
driving.
FLUID FILL LOCATIONS AND LUBRICATION
POINTS
The fluid fill/check locations and lubrication points
are located in each applicable group.
HEAVY DUTY SCHEDULE ªAº
6,000 miles (10 000 km) or at 6 months
²Change engine oil.
²Replace engine oil filter.
12,000 Miles (19 000 km) or at 12 months
²Change engine oil.
²Replace engine oil filter.
²Inspect engine air cleaner element, replace
as necessary (8.0L only).
18,000 Miles (29 000 km) or at 18 months
²Change engine oil.
²Replace engine oil filter.
²Inspect brake linings
²Inspect front wheel bearings. Clean and repack,
if required (4x4).
24,000 Miles (38 000 km) or at 24 months
²Change engine oil.
²Replace engine oil filter.
²Replace engine air cleaner element and air
pump filter.
²Clean and lubricate crankcase inlet air filter
(5.9L).
²Drain and refill automatic transmission fluid.
Replace filter and adjust bands.
²Inspect front wheel bearings. Clean and repack,
if required (4x2).
30,000 Miles (48 000 km) or at 30 months
²Change engine oil.
²Replace engine oil filter.
²Replace spark plugs.
36,000 Miles (58 000 km) or at 36 months
²Change engine oil.
²Replace engine oil filter.
BR/BELUBRICATION & MAINTENANCE 0 - 17
MAINTENANCE SCHEDULES (Continued)

²Flush and replace engine coolant if it has been
30,000 miles (48 000 km) or 24 months since last
change.
²Inspect front wheel bearings. Clean and repack,
if required (4x4).
²Inspect engine air cleaner element, replace
as necessary (8.0L only).
*Requires Service Reminder Indicator Light. If so
equipped, these parts are to be replaced at the indi-
cated mileage or when the service reminder indicator
light remains on continuously with the key in the
ªONº position, whichever occurs first.
HEAVY DUTY SCHEDULE ªBº
Follow this schedule if the vehicle is usually oper-
ated under one or more of the following conditions.
²Frequent short trips driving less than 5 miles
(8km)
²Frequent driving in dusty conditions
²Frequent trailer towing
²Extensive idling
²More than 50% of the driving is at sustained
high speeds during hot weather, above 90ÉF (32ÉC)
3,000 Miles (5 000 km)
²Change engine oil.
²Replace engine oil filter.
²Lubricate tie rod ends every 3,000 miles (5 000
km).
6,000 Miles (10 000 km)
²Change engine oil.
²Replace engine oil filter.
²Lubricate tie rod ends every 3,000 miles (5 000
km).
²Inspect front wheel bearings (4x4).
9,000 Miles (14 000 km)
²Change engine oil.
²Replace engine oil filter.
²Lubricate tie rod ends every 3,000 miles (5 000
km).
²Inspect front wheel bearings (4x2).
12,000 Miles (19 000 km)
²Change engine oil.
²Replace engine oil filter.
²Inspect engine air cleaner element and air
pump filter, replace as necessary.
²Drain and refill automatic transmission fluid.
Replace filter and adjust bands.³
²Change rear axle fluid.
²Change front axle fluid (4x4).
²Inspect brake linings.
²Lubricate tie rod ends every 3,000 miles (5 000
km).
²Inspect front wheel bearings (4x4).
15,000 Miles (24 000 km)
²Change engine oil.
²Replace engine oil filter.
²Lubricate tie rod ends every 3,000 miles (5 000
km).
18,000 Miles (29 000 km)
²Change engine oil.
²Replace engine oil filter.
²Lubricate tie rod ends every 3,000 miles (5 000
km).
²Inspect front wheel bearings (4x4).
²Inspect front wheel bearings (4x2).
²Drain and refill transfer case fluid every 18,000
miles (4x4).
21,000 Miles (34 000 km)
²Change engine oil.
²Replace engine oil filter.
²Lubricate tie rod ends every 3,000 miles (5 000
km).
24,000 Miles (38 000 km)
²Change engine oil
²Replace engine oil filter.
²Replace engine air cleaner element and air
pump filter.
²Drain and refill automatic transmission fluid.
Replace filter and adjust bands.
²Change rear axle fluid.
²Change front axle fluid (4x4).
²Clean and lubricate crankcase inlet air filter
(5.9L).
²Inspect front wheel bearings. Clean and repack,
if required (4x2).
²Inspect brake linings.
²Lubricate tie rod ends every 3,000 miles (5 000
km).
²Inspect front wheel bearings (4x4).
27,000 Miles (43 000 km)
²Change engine oil.
²Replace engine oil filter.
²Lubricate tie rod ends every 3,000 miles (5 000
km).
²Inspect front wheel bearings (4x2).
30,000 Miles (48 000 km)
²Change engine oil.
²Replace engine oil filter.
²Lubricate tie rod ends every 3,000 miles (5 000
km).
²Inspect PCV valve, replace as necessary
(5.9L).
²Replace spark plugs.
²Inspect front wheel bearings (4x4).
BR/BELUBRICATION & MAINTENANCE 0 - 19
MAINTENANCE SCHEDULES (Continued)

99,000 Miles (156 000 km)
²Change engine oil.
²Replace engine oil filter.
²Lubricate tie rod ends every 3,000 miles (5 000
km).
²Inspect front wheel bearings (4x2).
102,000 Miles (163 000 km)
²Change engine oil.
²Replace engine oil filter.
²Lubricate tie rod ends every 3,000 miles (5 000
km).
²Inspect front wheel bearings (4x4).
105,000 Miles (168 000 km)
²Change engine oil.
²Replace engine oil filter.
²Lubricate tie rod ends every 3,000 miles (5 000
km).
108,000 Miles (173 000 km)
²Change engine oil.
²Replace engine oil filter.
²Inspect engine air cleaner element and air
pump filter, replace as necessary.
²Drain and refill automatic transmission fluid.
Replace filter and adjust bands.³
²Drain and refill transfer case fluid (4x4).
²Change rear axle fluid.
²Change front axle fluid (4x4).
²Inspect brake linings.
²Flush and replace engine coolant if it has been
30,000 miles (48 000 km) since last change.
²Lubricate tie rod ends every 3,000 miles (5 000
km).
²Inspect front wheel bearings (4x4).
²Inspect front wheel bearings (4x2).
*Requires Service Reminder Indicator Light. If so
equipped, these parts are to be replaced at the indi-
cated mileage or when the service reminder indicator
light remains on continuously with the key in the
ªONº position, whichever occurs first.
³Off-the-highway operation, trailer towing, snow
plowing, prolonged operation with heavy loading,
especially in hot weather require the more frequent
transmission service indicated witha³inSchedule
ªBº. Perform these services if you usually operate
your Ram Truck under these conditions.
Inspection and service should also be performed
anytime a malfunction is observed or suspected.
DESCRIPTION - MAINTENANCE SCHEDULES
Ð 24±VALVE CUMMINS TURBO DIESEL
There are two maintenance schedules that show
proper service for the vehicle.First is ScheduleªA.ºIt lists all the scheduled
maintenance to be performed under ªnormalº operat-
ing conditions.
Second is ScheduleªB.ºIt is a schedule for vehicles
that are operated under the conditions listed at the
beginning of that schedule.
Use the schedule that best describes the driving
conditions.
Where time and mileage are listed, follow the
interval that occurs first.
At Each Stop For Fuel
²Check engine oil level and add as required.
²Check windshield washer solvent and add if
required.
²Clean windshield and wiper blades as required.
²Drain water from fuel filter.
Once A Month
²Check tire pressure and look for unusual wear
or damage.
²Inspect battery and clean and tighten terminals
as required.
²Check fluid levels of coolant reservoir, brake
master cylinder, power steering, and transmission.
Add fluid as required.
²Check all lights and all other electrical items for
correct operation.
²Check Filter Mindery. Replace air cleaner
element if necessary.
²Inspect and clean wiper blades. Replace if
required.
At Each Oil Change
²Inspect exhaust system.
²Inspect brake hoses.
²Adjust rear brakes.
²Rotate the tires at each oil change interval
shown at 7, 5000 miles (12 000 km) on schedule ªAº
or every other interval shown at 7,500 miles (12 000
km) on schedule ªBº.
²Check engine coolant level, hoses, and clamps.
²Lubricate steering linkage.
²Drain crankcase breather canister (if equipped).
EMISSION CONTROL SYSTEM MAINTENANCE
The scheduled emission maintenance listed inbold
typeon the Maintenance Schedules, must be done at
the mileage specified to assure the continued proper
functioning of the emission control system. These,
and all other maintenance services included in this
manual, should be done to provide the best vehicle
performance and reliability. More frequent mainte-
nance may be needed for vehicles in severe operating
conditions such as dusty areas and very short trip
driving.
0 - 22 LUBRICATION & MAINTENANCEBR/BE
MAINTENANCE SCHEDULES (Continued)

²Flush and replace engine coolant if it has been
30,000 miles (48 000 km) or 24 months since last
change.
105,000 Miles (168 000 km) or at 84 months
²Change engine oil and filter.
²Drain crankcase breather canister (if equipped).
²Inspect water pump weep hole for blockage.
²Replace fuel filter and clean water in fuel sen-
sor.
²Flush and replace engine coolant if it has been
30,000 miles (48 000 km) or 24 months since last
change.
112,500 Miles (181 000 km) or at 90 months
²Change engine oil and filter.
²Drain crankcase breather canister (if equipped).
²Inspect drive belts, replace if necessary.
²Inspect brake linings.
120,000 Miles (193 000 km) or at 96 months
²Change engine oil and filter.
²Drain crankcase breather canister (if equipped).
²Drain and refill automatic transmission fluid.
Replace filter and adjust bands.
²Inspect fan hub.
²Inspect damper.
²Inspect front wheel bearings. Clean and repack,
if required (4x2).
²Inspect water pump weep hole for blockage.
²Replace fuel filter and clean water in fuel sen-
sor.
127,500 Miles (205 000 km) or at 102 months
²Change engine oil and filter.
²Drain crankcase breather canister (if equipped).
135,000 Miles (217 000 km) or at 108 months
²Change engine oil and filter.
²Drain crankcase breather canister (if equipped).
²Inspect drive belts, replace as necessary.
²Inspect water pump weep hole for blockage.
²Replace fuel filter and clean water in fuel sen-
sor.
²Drain and refill transfer case fluid.
²Inspect brake linings.
²Flush and replace engine coolant if it has been
30,000 miles (48 000 km) or 24 months since last
change.
142,500 Miles (229 000 km) or at 114 months
²Change engine oil and filter.
²Drain crankcase breather canister (if equipped).
²Drain and refill automatic transmission fluid.
Replace filter and adjust bands.
²Inspect fan hub.
²Inspect damper.²Inspect front wheel bearings. Clean and repack,
if required (4x2).
²Inspect water pump weep hole for blockage.
150,000 Miles (241 000 km) or at 150 months
²Change engine oil and filter.
²Drain crankcase breather canister (if equipped).
²Adjust valve lash clearance.
²Replace fuel filter and clean water in fuel sen-
sor.
SCHEDULE ªBº
Follow this schedule if you usually operate your
vehicle under one or more of the following conditions.
²Frequent short driving less than 5 miles (8 km);
²Frequent driving in dusty conditions;
²Frequent trailer towing;
²Extensive idling;
²More than 50% of your driving is at sustained
high speeds during hot weather, above 90ÉF (32ÉC).
3,750 Miles (6 000 km)
²Change engine oil and filter.
²Drain crankcase breather canister (if equipped).
7,500 Miles (12 000 km)
²Change engine oil and filter.
²Drain crankcase breather canister (if equipped).
²Replace fuel filter and clean water in fuel sen-
sor.
11,250 Miles (18 000 km)
²Change engine oil and filter.
²Drain crankcase breather canister (if equipped).
15,000 Miles (24 000 km)
²Change engine oil and filter.
²Drain crankcase breather canister (if equipped).
²Inspect water pump weep hole for blockage.
²Replace fuel filter and clean water in fuel sen-
sor.
²Drain and refill automatic transmission fluid.
Replace filter and adjust bands.
²Change rear axle fluid.
²Change front axle fluid (4x4).
²Inspect brake linings.
18,750 Miles (30 000 km)
²Change engine oil and filter.
²Drain crankcase breather canister (if equipped).
22,500 Miles (36 000 km)
²Change engine oil and filter.
²Drain crankcase breather canister (if equipped).
²Inspect drive belts, replace as necessary.
²Replace fuel filter and clean water in fuel sen-
sor.
0 - 24 LUBRICATION & MAINTENANCEBR/BE
MAINTENANCE SCHEDULES (Continued)

COOLING
TABLE OF CONTENTS
page page
COOLING
DESCRIPTION............................1
OPERATION.............................2
DIAGNOSIS AND TESTING..................4
PRELIMINARY CHECKS...................4
ON-BOARD DIAGNOSTICS (OBD)...........4
COOLING SYSTEM LEAKS................5
COOLING SYSTEM GAS ENGINE...........7
COOLING SYSTEM DIESEL ENGINE........12
STANDARD PROCEDURE..................15
DRAINING COOLING SYSTEM - 3.9L/5.2L/
5.9L/8.0L ENGINES......................15
DRAINING COOLING SYSTEM - 5.9L
DIESEL ENGINE........................15REFILLING COOLING SYSTEM - 3.9L/5.2L/
5.9L/8.0L ENGINES......................15
REFILLING COOLING SYSTEM - 5.9L
DIESEL ENGINE........................15
ADDING ADDITIONAL COOLANT...........16
COOLANT LEVEL CHECK................16
COOLING SYSTEM CLEANING/REVERSE
FLUSHING............................16
COOLANT SELECTION-ADDITIVES.........17
SPECIFICATIONS........................17
SPECIAL TOOLS.........................18
ACCESSORY DRIVE......................19
ENGINE................................39
TRANSMISSION.........................79
COOLING
DESCRIPTIONÐCOOLING SYSTEM FLOW -
3.9L/5.2L/5.9L ENGINE
The cooling system regulates engine operating tem-
perature. It allows the engine to reach normal oper-
ating temperature as quickly as possible. It also
maintains normal operating temperature and pre-
vents overheating.
The cooling system also provides a means of heat-
ing the passenger compartment and cooling the auto-
matic transmission fluid (if equipped). The cooling
system is pressurized and uses a centrifugal water
pump to circulate coolant throughout the system.
An optional factory installed maximum duty cool-
ing package is available on most models. This pack-
age will provide additional cooling capacity forvehicles used under extreme conditions such as
trailer towing in high ambient temperatures (Fig. 1).
DESCRIPTIONÐCOOLING SYSTEM FLOW -
5.9L DIESEL
The diesel engine cooling system consists of (Fig.
2):
²Cross-flow radiator
²Belt driven water pump
²Belt driven mechanical cooling fan
²Thermal viscous fan drive
²Fan shroud
²Radiator pressure cap
²Vertically mounted thermostat
²Coolant reserve/recovery system
²Transmission oil cooler
²Coolant
BR/BECOOLING 7 - 1

OPERATIONÐCOOLING SYSTEM
The cooling system regulates engine operating tem-
perature. It allows the engine to reach normal oper-
ating temperature as quickly as possible. It also
maintains normal operating temperature and pre-
vents overheating.
The cooling system also provides a means of heat-
ing the passenger compartment and cooling the auto-
matic transmission fluid (if equipped). The cooling
system is pressurized and uses a centrifugal water
pump to circulate coolant throughout the system.
An optional factory installed maximum duty cool-
ing package is available on most models. This pack-
age will provide additional cooling capacity for
vehicles used under extreme conditions such as
trailer towing in high ambient temperatures.
DIAGNOSIS AND TESTING - PRELIMINARY
CHECKS
ENGINE COOLING SYSTEM OVERHEATING
Establish what driving conditions caused the com-
plaint. Abnormal loads on the cooling system such as
the following may be the cause:
²PROLONGED IDLE
²VERY HIGH AMBIENT TEMPERATURE
²SLIGHT TAIL WIND AT IDLE
²SLOW TRAFFIC
²TRAFFIC JAMS
²HIGH SPEED OR STEEP GRADES
Driving techniques that avoid overheating are:
²Idle with A/C off when temperature gauge is at
end of normal range.²Increasing engine speed for more air flow is rec-
ommended.
TRAILER TOWING:
Consult Trailer Towing section of owners manual.
Do not exceed limits.
AIR CONDITIONING; ADD-ON OR AFTER MARKET:
A maximum cooling package should have been
ordered with vehicle if add-on or after market A/C is
installed. If not, maximum cooling system compo-
nents should be installed for model involved per
manufacturer's specifications.
RECENT SERVICE OR ACCIDENT REPAIR:
Determine if any recent service has been per-
formed on vehicle that may effect cooling system.
This may be:
²Engine adjustments (incorrect timing)
²Slipping engine accessory drive belt(s)
²Brakes (possibly dragging)
²Changed parts. Incorrect water pump or pump
rotating in wrong direction due to belt not correctly
routed
²Reconditioned radiator or cooling system refill-
ing (possibly under filled or air trapped in system).
NOTE: If investigation reveals none of the previous
items as a cause for an engine overheating com-
plaint, (Refer to 7 - COOLING - DIAGNOSIS AND
TESTING)
DIAGNOSIS AND TESTINGÐON-BOARD
DIAGNOSTICS (OBD)
COOLING SYSTEM RELATED DIAGNOSTICS
The powertrain control module (PCM) has been
programmed to monitor certain cooling system com-
ponents:
²If the engine has remained cool for too long a
period, such as with a stuck open thermostat, a Diag-
nostic Trouble Code (DTC) can be set.
²If an open or shorted condition has developed in
the relay circuit controlling the electric radiator fan,
a Diagnostic Trouble Code (DTC) can be set.
If the problem is sensed in a monitored circuit
often enough to indicated an actual problem, a DTC
is stored. The DTC will be stored in the PCM mem-
ory for eventual display to the service technician.
(Refer to 25 - EMISSIONS CONTROL - DESCRIP-
TION).
Fig. 4 Spring Clamp Size Location
1 - SPRING CLAMP SIZE LOCATION
7 - 4 COOLINGBR/BE
COOLING (Continued)

DIAGNOSIS AND TESTING - COOLING SYSTEM
GAS ENGINE
COOLING SYSTEM DIAGNOSISÐGASOLINE ENGINE
CONDITION POSSIBLE CAUSES CORRECTION
TEMPERATURE
GAUGE READS LOW1. Has a Diagnostic Trouble Code (DTC)
been set indicating a stuck open
thermostat?1. (Refer to 25 - EMISSIONS CONTROL -
DESCRIPTION) for On-Board Diagnostics
and DTC information. Replace thermostat
if necessary.
2. Is the temperature sending unit
connected?2. Check the temperature sensor
connector. (Refer to 8 - ELECTRICAL/
INSTRUMENT CLUSTER - SCHEMATIC -
ELECTRICAL) Repair connector if
necessary.
3. Is the temperature gauge operating
OK?3. Check gauge operation. (Refer to 8 -
ELECTRICAL/INSTRUMENT CLUSTER/
ENGINE TEMPERATURE GAUGE -
DESCRIPTION) . Repair as necessary.
4. Coolant level low in cold ambient
temperatures accompanied with poor
heater performance.4. Check coolant level in the coolant
reserve/overflow tank and the radiator.
Inspect system for leaks. Repair leaks as
necessary. Refer to the Coolant section of
the manual text for WARNINGS and
CAUTIONS associated with removing the
radiator cap.
5. Improper operation of internal heater
doors or heater controls.5. Inspect heater and repair as necessary.
(Refer to 24 - HEATING & AIR
CONDITIONING - DIAGNOSIS AND
TESTING) for procedures.
TEMPERATURE
GAUGE READS HIGH
OR THE COOLANT
WARNING LAMP
ILLUMINATES.
COOLANT MAY OR
MAY NOT BE LOST OR
LEAKING FROM THE
COOLING SYSTEM1. Trailer is being towed, a steep hill is
being climbed, vehicle is operated in slow
moving traffic, or engine is being idled
with very high ambient (outside)
temperatures and the air conditioning is
on. Higher altitudes could aggravate
these conditions.1. This may be a temporary condition and
repair is not necessary. Turn off the air
conditioning and attempt to drive the
vehicle without any of the previous
conditions. Observe the temperature
gauge. The gauge should return to the
normal range. If the gauge does not
return to the normal range, determine the
cause for overheating and repair. Refer to
Possible Causes (2-20).
2. Is the temperature gauge reading
correctly?2. Check gauge. (Refer to 8 -
ELECTRICAL/INSTRUMENT CLUSTER -
SCHEMATIC - ELECTRICAL) . Repair as
necessary.
3. Is the temperature warning illuminating
unnecessarily?3. (Refer to 8 - ELECTRICAL/
INSTRUMENT CLUSTER - SCHEMATIC -
ELECTRICAL).
4. Coolant low in coolant reserve/overflow
tank and radiator?4. Check for coolant leaks and repair as
necessary. (Refer to 7 - COOLING -
DIAGNOSIS AND TESTING).
BR/BECOOLING 7 - 7
COOLING (Continued)