air conditioning DODGE RAM 2001 Service User Guide

ENGINE COOLANT
THERMOSTAT - 3.9L/5.2L/5.9L
DESCRIPTION
CAUTION: Do not operate an engine without a ther-
mostat, except for servicing or testing.
The thermostat on the 3.9L, 5.2L and 5.9L gas
powered engines is located beneath the thermostat
housing at the front of the intake manifold (Fig. 15).
The thermostat is a wax pellet driven, reverse pop-
pet choke type.
Coolant leakage into the pellet container will cause
the thermostat to fail in the open position. Thermo-
stats very rarely stick. Do not attempt to free a ther-
mostat with a prying device.
The same thermostat is used for winter and sum-
mer seasons. An engine should not be operated with-
out a thermostat, except for servicing or testing.
Operating without a thermostat causes longer engine
warmup time, unreliable warmup performance,
increased exhaust emissions and crankcase condensa-
tion that can result in sludge formation.
OPERATION
The wax pellet is located in a sealed container at
the spring end of the thermostat. When heated, the
pellet expands, overcoming closing spring tension
and water pump pressure to force the valve to open.
DIAGNOSIS AND TESTINGÐTHERMOSTAT
ON-BOARD DIAGNOSTICS
Allgasoline powered modelsare equipped with
On-Board Diagnostics for certain cooling system com-
ponents. Refer to On-Board Diagnostics (OBD) in the
Diagnosis section of this group for additional infor-
mation. If the powertrain control module (PCM)
detects low engine coolant temperature, it will record
a Diagnostic Trouble Code (DTC) in the PCM mem-
ory. Do not change a thermostat for lack of heat as
indicated by the instrument panel gauge or by poor
heater performance unless a DTC is present. Refer to
the Diagnosis section of this group for other probable
causes. For other DTC numbers, (Refer to 25 - EMIS-
SIONS CONTROL - DESCRIPTION).
The DTC can also be accessed through the DRB
scan tool. Refer to the appropriate Powertrain Diag-
nostic Procedures information for diagnostic informa-
tion and operation of the DRB scan tool.
REMOVAL
WARNING: DO NOT LOOSEN RADIATOR DRAIN-
COCK WITH SYSTEM HOT AND PRESSURIZED.
SERIOUS BURNS FROM COOLANT CAN OCCUR.
Do not waste reusable coolant. If solution is clean,
drain coolant into a clean container for reuse.
If thermostat is being replaced, be sure that
replacement is specified thermostat for vehicle model
and engine type.
Factory installed thermostat housings on 3.9L,
5.2L and 5.9L engines are installed on a gasket with
an anti-stick coating. This will aid in gasket removal
and clean-up.
(1) Disconnect negative battery cable at battery.
(2) Drain cooling system until coolant level is
below thermostat (Refer to 7 - COOLING - STAN-
DARD PROCEDURE).
(3) Air Conditioned vehicles: Remove support
bracket (generator mounting bracket-to-intake mani-
fold) located near rear of generator (Fig. 16).
NOTE: On air conditioning equipped vehicles, the
generator must be partially removed.
Fig. 15 ThermostatÐ5.2L and 5.9L Gas Powered
Engines
1 - THERMOSTAT HOUSING
2 - GASKET
3 - INTAKE MANIFOLD
4 - THERMOSTAT
5 - MACHINED GROOVE
BR/BEENGINE 7 - 49

CAUTION: A number or letter is stamped into the
tongue of constant tension clamps. If replacement
is necessary, use only an original equipment clamp
with a matching number or letter.
(3) Remove hose clamps and hoses from radiator.
(4) Remove coolant reserve/overflow tank hose
from radiator filler neck nipple.
(5) Remove the coolant reserve/overflow tank from
the fan shroud (pull straight up). The tank slips into
T-slots on the fan shroud (Fig. 33).
(6) Disconnect electrical connectors at windshield
washer reservoir tank and remove tank.
(7) Remove the four fan shroud mounting bolts
(Fig. 34). Position shroud rearward over the fan
blades towards engine.
(8) Remove the plastic clips retaining the rubber
shields to the sides of radiator. Position rubber
shields to the side.
(9) Remove the two radiator upper mounting bolts
(Fig. 35).
(10) Lift radiator straight up and out of engine
compartment. The bottom of the radiator is equipped
with two alignment dowels that fit into holes in the
lower radiator support panel (Fig. 35). Rubber bis-
cuits (insulators) are installed to these dowels. Take
care not to damage cooling fins or tubes on the radi-
ator and air conditioning condenser when removing.
CLEANING
Clean radiator fins are necessary for good heat
transfer. The radiator and air conditioning fins
should be cleaned when an accumulation of debris
has occurred. With the engine cold, apply cold water
Fig. 33 Coolant Recovery Bottle
1 - T-SLOTS
2 - ALIGNMENT PIN
3 - FAN SHROUD
4 - COOLANT RESERVE/OVERFLOW TANK
Fig. 34 Fan Shroud MountingÐ3.9L/5.2L/5.9L
Engines
1 - RADIATOR SUPPORT
2 - RADIATOR
3 - BOLTS (4)
4 - FAN SHROUD
Fig. 35 Typical Radiator Mounting
1 - MOUNTING BOLTS
2 - RADIATOR
3 - ALIGNMENT DOWELS (2)
4 - RADIATOR SUPPORT
7 - 60 ENGINEBR/BE
RADIATOR - 3.9L/5.2L/5.9L (Continued)

REMOVAL
(1) Disconnect battery negative cables.
WARNING: DO NOT REMOVE THE CYLINDER
BLOCK DRAIN PLUGS OR LOOSEN THE RADIATOR
DRAINCOCK WITH THE SYSTEM HOT AND UNDER
PRESSURE. SERIOUS BURNS FROM COOLANT
CAN OCCUR.
(2) Drain the cooling system (Refer to 7 - COOL-
ING - STANDARD PROCEDURE).
WARNING: CONSTANT TENSION HOSE CLAMPS
ARE USED ON MOST COOLING SYSTEM HOSES.
WHEN REMOVING OR INSTALLING, USE ONLY
TOOLS DESIGNED FOR SERVICING THIS TYPE OF
CLAMP, SUCH AS SPECIAL CLAMP TOOL (NUMBER
6094). SNAP-ON CLAMP TOOL (NUMBER HPC-20)
MAY BE USED FOR LARGER CLAMPS. ALWAYS
WEAR SAFETY GLASSES WHEN SERVICING CON-
STANT TENSION CLAMPS.
CAUTION: A number or letter is stamped into the
tongue of constant tension clamps. If replacement
is necessary, use only an original equipment clamp
with a matching number or letter.
(3) Remove hose clamps and hoses from radiator.
(4) Remove coolant reserve/overflow tank hose
from radiator filler neck nipple.
(5) The coolant recovery/reservoir does not require
removal. Disconnect the overflow hose from the radi-
ator.
(6) Disconnect electrical connectors at windshield
washer reservoir tank and remove tank.
(7) Remove the four fan shroud mounting bolts
(Fig. 37). Position shroud rearward over the fan
blades towards engine.
(8) Remove the two radiator upper mounting bolts
(Fig. 38).
(9) Lift radiator straight up and out of engine com-
partment. The bottom of the radiator is equipped
with two alignment dowels that fit into holes in the
lower radiator support panel (Fig. 38). Rubber bis-
cuits (insulators) are installed to these dowels. Take
care not to damage cooling fins or tubes on the radi-
ator and air conditioning condenser when removing.
CLEANING
Clean radiator fins are necessary for good heat
transfer. The radiator and air conditioning fins
should be cleaned when an accumulation of debris
has occurred. With the engine cold, apply cold water
and compressed air to the back (engine side) of the
radiator to flush the radiator and/or A/C condenser of
debris.
INSPECTION
Inspect the radiator side tanks for cracks, broken
or missing fittings also inspect the joint where the
tanks seam up to the radiator core for signs of leak-
age and/or deteriorating seals.
Fig. 37 Fan Shroud MountingÐ8.0L Engine
1 - RADIATOR SUPPORT
2 - RADIATOR
3 - BOLTS (4)
4 - FAN SHROUD
Fig. 38 Typical Radiator Mounting
1 - MOUNTING BOLTS
2 - RADIATOR
3 - ALIGNMENT DOWELS (2)
4 - RADIATOR SUPPORT
7 - 62 ENGINEBR/BE
RADIATOR - 8.0L (Continued)

(10) Lift radiator straight up and out of engine
compartment. The bottom of the radiator is equipped
with two alignment dowels that fit into holes in the
lower radiator support panel (Fig. 42). Rubber bis-
cuits (insulators) are installed to these dowels. Take
care not to damage cooling fins or tubes on the radi-
ator and air conditioning condenser when removing.
CLEANING
Clean radiator fins are necessary for good heat
transfer. The radiator and air conditioning fins
should be cleaned when an accumulation of debris
has occurred. With the engine cold, apply cold water
and compressed air to the back (engine side) of the
radiator to flush the radiator and/or A/C condenser of
debris.
INSPECTION
Inspect the radiator side tanks for cracks, broken
or missing fittings also inspect the joint where the
tanks seam up to the radiator core for signs of leak-
age and/or deteriorating seals.
Inspect radiator core for corroded, bent or missing
cooling fins. Inspect the core for bent or damaged
cooling tubes.
INSTALLATION
(1) Position fan shroud over the fan blades rear-
ward towards engine.
(2) Install rubber insulators to alignment dowels
at lower part of radiator.
(3) Lower the radiator into position while guiding
the two alignment dowels into lower radiator sup-
port. Different alignment holes are provided in the
lower radiator support for each engine application.
(4) Install two upper radiator mounting bolts.
Tighten bolts to 11 N´m (95 in. lbs.) torque.
(5) Connect both radiator hoses and install hose
clamps.
(6) Connect transmission cooler lines to radiator
tank. Inspect quick connect fittings for debris and
install until an audible ªclickº is heard. Pull apart to
verify connection.
(7) Install windshield washer reservoir tank.
(8) Position fan shroud to flanges on sides of radi-
ator. Install fan shroud mounting bolts (Fig. 41).
Tighten bolts to 6 N´m (50 in. lbs.) torque.
(9) Install metal clips to top of fan shroud.
(10) Install coolant reserve/overflow tank hose to
radiator filler neck nipple.
(11) Install coolant reserve/overflow tank to fan
shroud (fits into T-slots on shroud).
(12) Install battery negative cables.
(13) Install positive battery cable to top of radia-
tor. Tighten radiator-to-battery cable mounting nuts.
(14) Position heater controls tofull heatposition.(15) Fill cooling system with coolant (Refer to 7 -
COOLING - STANDARD PROCEDURE).
(16) Operate engine until it reaches normal tem-
perature. Check cooling system and automatic trans-
mission (if equipped) fluid levels.
RADIATOR PRESSURE CAP
DESCRIPTION
Radiators are equipped with a pressure cap, which
releases pressure at some point within a range of
97-124 kPa (14-18 psi). The pressure relief point (in
pounds) is engraved on top of cap.
The cooling system will operate at pressures
slightly above atmospheric pressure. This results in a
higher coolant boiling point allowing increased radi-
ator cooling capacity.
A rubber gasket seals radiator filler neck to pre-
vent leakage. This is done to keep system under
pressure. It also maintains vacuum during coolant
cool-down allowing coolant to return from reserve/
overflow tank.
OPERATION
The cap (Fig. 43) contains a spring-loaded pressure
relief valve that opens when system pressure reaches
release range of 97-124 kPa (14-18 psi).
A vent valve in the center of cap allows a small
coolant flow through cap when coolant is below boil-
ing temperature. The valve is completely closed when
boiling point is reached. As the coolant cools, it con-
Fig. 43 Radiator Pressure Cap and Filler NeckÐ
Typical
1 - STAINLESS-STEEL SWIVEL TOP
2 - RUBBER SEALS
3 - VENT VALVE
4 - RADIATOR TANK
5 - FILLER NECK
6 - OVERFLOW NIPPLE
7 - MAIN SPRING
8 - GASKET RETAINER
BR/BEENGINE 7 - 65
RADIATOR - 5.9L DIESEL (Continued)

ket has swollen and prevents vent valve from open-
ing, replace cap.
Hold cap at eye level, upside down. If any light can
be seen between vent valve and rubber gasket,
replace cap.Do not use a replacement cap that
has a spring to hold vent shut.A replacement cap
must be the type designed for a coolant reserve/over-
flow system with a completely sealed diaphragm
spring and a rubber gasket. This gasket is used to
seal to radiator filler neck top surface. Use of proper
cap will allow coolant return to radiator.
WATER PUMP - 3.9L/5.2L/5.9L
DESCRIPTION
The water pump is located on the engine front
cover, and has an integral pulley attached (Fig. 46).
The water pump impeller is pressed onto the rear
of a shaft that rotates in a bearing pressed into the
water pump body. The body has a small hole for ven-
tilation. The water pump seals are lubricated by
antifreeze in the coolant mixture. Additional lubrica-
tion is not necessary.
OPERATION
A centrifugal water pump circulates coolant
through the water jackets, passages, intake manifold,
radiator core, cooling system hoses and heater core,
this coolant absorbs the heat generated when the
engine is running. The pump is driven by the engine
crankshaft via a drive belt.
DIAGNOSIS AND TESTINGÐWATER PUMP
A quick test to determine if pump is working is to
check if heater warms properly. A defective water
pump will not be able to circulate heated coolant
through the long heater hose to the heater core.
REMOVAL
The water pump on all models can be removed
without discharging the air conditioning system (if
equipped).
The water pump on all gas powered engines is
bolted directly to the engine timing chain case/cover.
On all 3.9L/5.2L/5.9L gas powered engines, a gas-
ket is used as a seal between the water pump and
timing chain case/cover.
If water pump is replaced because of bearing/shaft
damage or leaking shaft seal, the mechanical cooling
fan assembly should also be inspected. Inspect for
fatigue cracks, loose blades or loose rivets that could
have resulted from excessive vibration. Replace fan if
any of these conditions are found. Also check condi-
tion of the thermal viscous fan drive (Refer to 7 -
COOLING/ENGINE/FAN DRIVE VISCOUS
CLUTCH - DIAGNOSIS AND TESTING).
(1) Disconnect negative cable from battery.
(2) Drain cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
Do not waste reusable coolant. If solution is clean,
drain coolant into a clean container for reuse.
(3) Remove windshield washer reservoir tank from
radiator fan shroud.
Fig. 45 Radiator Pressure Cap
1 - STAINLESS-STEEL SWIVEL TOP
2 - RUBBER SEALS
3 - VENT VALVE
4 - RADIATOR TANK
5 - FILLER NECK
6 - OVERFLOW NIPPLE
7 - MAIN SPRING
8 - GASKET RETAINER
Fig. 46 Water Pump LocationÐTypical
1 - WATER PUMP BYPASS HOSE
2 - FAN BLADE ASSEMBLY
3 - VISCOUS FAN DRIVE
4 - WATER PUMP AND PULLEY
BR/BEENGINE 7 - 67
RADIATOR PRESSURE CAP (Continued)

INSTALLATION
(1) Clean gasket mating surfaces.
(2) Using a new gasket, install water pump to
engine as follows: Guide water pump nipple into
bypass hose as pump is being installed. Install water
pump bolts (Fig. 52). Tighten water pump mounting
bolts to 40 N´m (30 ft. lbs.) torque.
(3) Position bypass hose clamp to bypass hose.
(4) Spin water pump to be sure that pump impel-
ler does not rub against timing chain case/cover.
(5) Install a new o-ring to the heater hose coolant
return tube (Fig. 51). Coat the new o-ring with anti-
freeze before installation.
(6) Install coolant return tube and its mounting
bolt to engine (Fig. 51). Be sure the slot in tube
bracket is bottomed to mounting bolt. This will prop-
erly position return tube.
(7) Connect radiator lower hose to water pump.
(8) Connect heater hose and hose clamp to coolant
return tube.
(9) Install drive belt (Refer to 7 - COOLING/AC-
CESSORY DRIVE/DRIVE BELTS - INSTALLATION)
(Fig. 50).
(10) Position fan shroud and fan blade/viscous fan
drive assembly to vehicle as a complete unit.
(11) Install fan shroud.
(12) Install fan blade/viscous fan drive assembly to
water pump shaft.
(13) Fill cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
(14) Connect negative battery cable.
(15) Start and warm the engine. Check for leaks.
WATER PUMP - 8.0L
DIAGNOSIS AND TESTINGÐWATER PUMP
A quick test to determine if pump is working is to
check if heater warms properly. A defective water
pump will not be able to circulate heated coolant
through the long heater hose to the heater core.
REMOVAL
NOTE: The water pump on all models can be
removed without discharging the air conditioning
system (if equipped).
The water pump on all gas powered engines is
bolted directly to the engine timing chain case/
cover.
On the 8.0L V-10 engine, a rubber o-ring (instead of
a gasket) is used as a seal between the water pump
and timing chain case/cover.If water pump is replaced because of bearing/shaft
damage or leaking shaft seal, the mechanical cooling
fan assembly should also be inspected. Inspect for
fatigue cracks, loose blades or loose rivets that could
have resulted from excessive vibration. Replace fan if
any of these conditions are found. Also check condi-
tion of the thermal viscous fan drive (Refer to 7 -
COOLING/ENGINE/FAN DRIVE VISCOUS
CLUTCH - DIAGNOSIS AND TESTING).
(1) Disconnect negative battery cable from battery.
(2) Drain cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
Do not waste reusable coolant. If solution is clean,
drain coolant into a clean container for reuse.
(3) Remove windshield washer reservoir tank from
radiator fan shroud.
(4) Remove the four fan shroud mounting bolts at
the radiator (Fig. 53). Do not attempt to remove
shroud from vehicle at this time.
WARNING: CONSTANT TENSION HOSE CLAMPS
ARE USED ON MOST COOLING SYSTEM HOSES.
WHEN REMOVING OR INSTALLING, USE ONLY
TOOLS DESIGNED FOR SERVICING THIS TYPE OF
CLAMP, SUCH AS SPECIAL CLAMP TOOL (NUMBER
6094). SNAP-ON CLAMP TOOL (NUMBER HPC-20)
MAY BE USED FOR LARGER CLAMPS. ALWAYS
WEAR SAFETY GLASSES WHEN SERVICING CON-
STANT TENSION CLAMPS.
Fig. 53 Typical Fan Shroud Mounting
1 - RADIATOR SUPPORT
2 - RADIATOR
3 - BOLTS (4)
4 - FAN SHROUD
7 - 70 ENGINEBR/BE
WATER PUMP - 3.9L/5.2L/5.9L (Continued)

²Water leaks from the shaft seal. This is evident
by traces of coolant below the vent hole
²Loose or rough turning bearing. Also inspect
thermal fan drive
²Impeller rubbing the pump body
INSTALLATION
(1) Install new O-ring seal in groove on water
pump (Fig. 62).
(2) Install water pump. Tighten mounting bolts to
24 N´m (18 ft. lbs.) torque.(3) Install accessory drive belt. Refer to procedure
in this group.
(4) Install the bolt retaining the wiring harness
near top of water pump.
(5) Fill cooling system. Refer to Refilling Cooling
System in this section.
(6) Connect both battery cables.
(7) Start and warm the engine. Check for leaks.
WATER PUMP INLET TUBE -
3.9L/5.2L/5.9L
REMOVALÐWATER PUMP BYPASS HOSE
WITH AIR CONDITIONING
If equipped with A/C, the generator and A/C com-
pressor along with their common mounting bracket
(Fig. 63) must be partially removed. Removing the
generator or A/C compressor from their mounting
bracket is not necessary. Also, discharging the A/C
system is not necessary.Do notremove any refriger-
ant lines from A/C compressor.
WARNING: THE A/C SYSTEM IS UNDER PRESSURE
EVEN WITH THE ENGINE OFF. REFER TO REFRIG-
ERANT WARNINGS IN 24 - HEATING AND AIR CON-
DITIONING.
(1) Disconnect negative battery cable from battery.
(2) Partially drain cooling system (Refer to 7 -
COOLING - STANDARD PROCEDURE).
Fig. 61 Water Pump Removal/Installation
1 - O-RING SEAL (SQUARE)
2 - WATER PUMP
3 - BOLT (2)
Fig. 62 Pump O-ring Seal
1 - O-RING SEAL
2 - GROOVE
3 - WATER PUMP
Fig. 63 GeneratorÐA/C Compressor Mounting
BracketÐTypical
7 - 74 ENGINEBR/BE
WATER PUMP - 5.9L DIESEL (Continued)

REMOVALÐWATER PUMP BYPASS HOSE
WITHOUT AIR CONDITIONING
A water pump bypass hose (Fig. 70) is used
between the intake manifold and water pump on all
gas powered engines. To test for leaks, refer to Test-
ing Cooling System for Leaks in this group.
(1) Partially drain cooling system (Refer to 7 -
COOLING - STANDARD PROCEDURE). Do not
waste reusable coolant. If the solution is clean, drain
the coolant into a clean container for reuse.
WARNING: CONSTANT TENSION HOSE CLAMPS
ARE USED ON MOST COOLING SYSTEM HOSES.
WHEN REMOVING OR INSTALLING, USE ONLY
TOOLS DESIGNED FOR SERVICING THIS TYPE OF
CLAMP, SUCH AS SPECIAL CLAMP TOOL (NUMBER
6094). SNAP-ON CLAMP TOOL (NUMBER HPC-20)
MAY BE USED FOR LARGER CLAMPS. ALWAYS
WEAR SAFETY GLASSES WHEN SERVICING CON-
STANT TENSION CLAMPS.
CAUTION: A number or letter is stamped into the
tongue of constant tension clamps. If replacement
is necessary, use only an original equipment clamp
with a matching number or letter.
(2) Loosen both bypass hose clamps and position to
the center of hose.
(3) Remove hose from vehicle.
INSTALLATIONÐWATER PUMP BYPASS HOSE
WITH AIR CONDITIONING
(1) Position bypass hose clamps to the center of
hose.
(2) Install bypass hose to engine.
(3) Secure both hose clamps.
(4) Install generator-A/C mounting bracket assem-
bly to engine. Tighten bolt number 1 (Fig. 63) to 41
N´m (30 ft. lbs.) torque. Tighten bolt number 2 (Fig.
63) to 28 N´m (20 ft. lbs.) torque. Tighten bracket
mounting bolts (Fig. 68) (Fig. 69) to 40 N´m (30 ft.
lbs.) torque.
(5) Install a new O-ring to the heater hose coolant
return tube (Fig. 66) (Fig. 67). Coat the new O-ring
with antifreeze before installation.
(6) Install coolant return tube and its mounting
bolt to engine (Fig. 66) (Fig. 67).
(7) Connect throttle body control cables.
(8) Install oil dipstick mounting bolt.
(9)3.9L V-6 or 5.2/5.9L V-8 LDC-Gas Engines:
Install idler pulley. Tighten bolt to 41 N´m (30 ft.
lbs.) torque.
(10)5.9L HDC-Gas:Install automatic belt ten-
sioner assembly to mounting bracket. A dowel pin is
located on back of tensioner (Fig. 71). Align this to
dowel hole (Fig. 72) in tensioner mounting bracket.
Tighten bolt to 41 N´m (30 ft. lbs.) torque.
(11) Install drive belt (Refer to 7 - COOLING/AC-
CESSORY DRIVE/DRIVE BELTS - INSTALLA-
TION).
Fig. 71 Tensioner Dowel PinÐ5.9L HDC-Gas Engine
1 - BELT TENSIONER
2 - DOWEL PIN
Fig. 70 Water Pump Bypass HoseÐTypical
1 - WATER PUMP BYPASS HOSE
2 - FAN BLADE ASSEMBLY
3 - VISCOUS FAN DRIVE
4 - WATER PUMP AND PULLEY
BR/BEENGINE 7 - 77
WATER PUMP INLET TUBE - 3.9L/5.2L/5.9L (Continued)

CAUTION: When installing the serpentine accessory
drive belt, the belt must be routed correctly. If not,
the engine may overheat due to the water pump
rotating in the wrong direction (Refer to 7 - COOL-
ING/ACCESSORY DRIVE/DRIVE BELTS - INSTALLA-
TION). The correct belt with the correct length must
be used.(12) Install air cleaner assembly.
(13) Install upper radiator hose to radiator.
(14) Connect throttle cable to clip at radiator fan
shroud.
(15) Connect wiring harness to A/C compressor.
(16) Fill cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
(17) Start and warm the engine. Check for leaks.
INSTALLATIONÐWATER PUMP BYPASS HOSE
WITHOUT AIR CONDITIONING
(1) Position bypass hose clamps to the center of
hose.
(2) Install bypass hose to engine.
(3) Secure both hose clamps.
(4) Fill cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
(5) Start and warm the engine. Check for leaks.
Fig. 72 Tensioner Mounting
1 - DOWEL PIN HOLE
2 - TENSIONER MOUNTING BRACKET
7 - 78 ENGINEBR/BE
WATER PUMP INLET TUBE - 3.9L/5.2L/5.9L (Continued)

TRANSMISSION
TABLE OF CONTENTS
page page
TRANS COOLER - 3.9L/5.2L/5.9L
DESCRIPTION...........................79
OPERATION.............................79
STANDARD PROCEDURE..................79
FLUSHING COOLERS AND TUBES - WITH
RADIATOR IN-TANK TRANSMISSION OIL
COOLER..............................79
FLUSHING COOLER AND TUBES -
WITHOUT RADIATOR IN-TANK
TRANSMISSION OIL COOLER.............80
REMOVAL..............................81
DISASSEMBLY...........................81
ASSEMBLY.............................82
INSTALLATION...........................82
TRANS COOLER - 8.0L
DESCRIPTION...........................82
OPERATION.............................82
STANDARD PROCEDURE..................83
FLUSHING COOLERS AND TUBES - WITH
RADIATOR IN-TANK TRANSMISSION OIL
COOLER..............................83FLUSHING COOLER AND TUBES -
WITHOUT RADIATOR IN-TANK
TRANSMISSION OIL COOLER.............83
REMOVAL..............................84
INSTALLATION...........................85
TRANS COOLER - 5.9L DIESEL
DESCRIPTION...........................85
OPERATION.............................85
STANDARD PROCEDURE..................85
FLUSHING COOLERS AND TUBES - WITH
RADIATOR IN-TANK TRANSMISSION OIL
COOLER..............................85
FLUSHING COOLER AND TUBES -
WITHOUT RADIATOR IN-TANK
TRANSMISSION OIL COOLER.............86
REMOVAL..............................87
INSTALLATION...........................88
TRANS COOLER - 3.9L/5.2L/
5.9L
DESCRIPTION
An air-to-oil transmission oil cooler is standard on
all engine packages. the cooler is located between the
radiator and air conditioning condenser (Fig. 1).
OPERATION
The transmission oil is routed through the cooler
where heat is removed from the transmission oil
before returning to the transmission. The cooler has
an internal thermostat that controls fluid flow
through the cooler. When the transmission fluid is
cold ( less than operating temperature) the fluid is
routed through the cooler bypass. when the transmis-
sion fluid reaches operating temperatures and above,the thermostat closes off the bypass allowing fluid
flow through the cooler. The thermostat MUST be
removed from the cooler before the cooler can be
flushed. The thermostat is serviceable.
STANDARD PROCEDURE - FLUSHING
COOLERS AND TUBES - WITH RADIATOR
IN-TANK TRANSMISSION OIL COOLER
When a transmission failure has contaminated the
fluid, the oil cooler(s) must be flushed. The torque
converter must also be replaced. This will insure that
metal particles or sludged oil are not later trans-
ferred back into the reconditioned (or replaced) trans-
mission.
The only recommended procedure for flushing cool-
ers and lines is to use Tool 6906-B Cooler Flusher.
BR/BETRANSMISSION 7 - 79