belt DODGE RAM 2003 Service User Guide
[x] Cancel search | Manufacturer: DODGE, Model Year: 2003, Model line: RAM, Model: DODGE RAM 2003Pages: 2895, PDF Size: 83.15 MB
Page 201 of 2895

BEARING NOISE
The axle shaft, differential and pinion bearings can
all produce noise when worn or damaged. Bearing
noise can be either a whining, or a growling sound.
Pinion bearings have a constant-pitch noise. This
noise changes only with vehicle speed. Pinion bearing
noise will be higher pitched because it rotates at a
faster rate. Drive the vehicle and load the differen-
tial. If bearing noise occurs, the rear pinion bearing
is the source of the noise. If the bearing noise is
heard during a coast, the front pinion bearing is the
source.
Worn or damaged differential bearings usually pro-
duce a low pitch noise. Differential bearing noise is
similar to pinion bearing noise. The pitch of differen-
tial bearing noise is also constant and varies only
with vehicle speed.
Axle shaft bearings produce noise and vibration
when worn or damaged. The noise generally changes
when the bearings are loaded. Road test the vehicle.
Turn the vehicle sharply to the left and to the right.
This will load the bearings and change the noise
level. Where axle bearing damage is slight, the noise
is usually not noticeable at speeds above 30 mph.
LOW SPEED KNOCK
Low speed knock is generally caused by a worn
U-joint or by worn side±gear thrust washers. A worn
pinion shaft bore will also cause low speed knock.
VIBRATION
Vibration at the rear of the vehicle is usually
caused by a:
²Damaged drive shaft.
²Missing drive shaft balance weight(s).²Worn or out-of-balance wheels.
²Loose wheel lug nuts.
²Worn U-joint(s).
²Loose/broken springs.
²Damaged axle shaft bearing(s).
²Loose pinion gear nut.
²Excessive pinion yoke run out.
²Bent axle shaft(s).
Check for loose or damaged front-end components
or engine/transmission mounts. These components
can contribute to what appears to be a rearend vibra-
tion. Do not overlook engine accessories, brackets
and drive belts.
NOTE: All driveline components should be exam-
ined before starting any repair.
DRIVELINE SNAP
A snap or clunk noise when the vehicle is shifted
into gear (or the clutch engaged), can be caused by:
²High engine idle speed.
²Transmission shift operation.
²Loose engine/transmission/transfer case mounts.
²Worn U-joints.
²Loose spring mounts.
²Loose pinion gear nut and yoke.
²Excessive ring gear backlash.
²Excessive side gear to case clearance.
The source of a snap or a clunk noise can be deter-
mined with the assistance of a helper. Raise the vehi-
cle on a hoist with the wheels free to rotate. Instruct
the helper to shift the transmission into gear. Listen
for the noise, a mechanics stethoscope is helpful in
isolating the source of a noise.
DIAGNOSTIC CHART
Condition Possible Causes Correction
Wheel Noise 1. Wheel loose. 1. Tighten loose nuts.
2. Faulty, brinelled wheel bearing. 2. Replace bearing.
Axle Shaft Noise 1. Misaligned axle tube. 1. Inspect axle tube alignment.
Correct as necessary.
2. Bent or sprung axle shaft. 2. Inspect and correct as necessary.
3 - 128 REAR AXLE - 11 1/2 AADR
REAR AXLE - 11 1/2 AA (Continued)
Page 254 of 2895

CONDITION POSSIBLE CAUSES CORRECTION
Brakes Self Apply 1. Dump valve faulty. 1. Replace booster.
2. Contamination in hydraulic
system.2. Flush hydraulic system and replace
booster.
3. Restriction in booster return hose. 3. Replace hose.
Booster Chatter, Pedal
Vibration1. Slipping pump belt. 1. Replace power steering belt.
2. Low pump fluid level. 2. Fill pump and check for leaks.
Grabbing Brakes 1. Low pump flow. 1. Test and repair/replace pump.
2. Faulty spool valve action. 2. Replace booster.
STANDARD PROCEDURE - BLEEDING
The hydraulic booster is generally self-bleeding,
this procedure will normally bleed the air from the
booster. Normal driving and operation of the unit will
remove any remaining trapped air.
(1) Fill power steering pump reservoir.
(2) Disconnect fuel shutdown relay and crank the
engine for several seconds, Refer to Fuel System for
relay location and WARNING.
(3) Check fluid level and add if necessary.
(4) Connect fuel shutdown relay and start the
engine.
(5) Turn the steering wheel slowly from lock to
lock twice.
(6) Stop the engine and discharge the accumulator
by depressing the brake pedal 5 times.
(7) Start the engine and turn the steering wheel
slowly from lock to lock twice.
(8) Turn off the engine and check fluid level and
add if necessary.
NOTE: If fluid foaming occurs, wait for foam to dis-
sipate and repeat steps 7 and 8.
REMOVAL
NOTE: If the booster is being replaced because the
power steering fluid is contaminated, flush the
power steering system before replacing the booster.
(1) With engine off depress the brake pedal 5
times to discharge the accumulator.
(2) Remove brake lines from master cylinder.
(3) Remove mounting nuts from the master cylin-
der.
(4) Remove the bracket from the hydraulic booster
lines and master cylinder mounting studs.
(5) Remove the master cylinder.
(6) Remove the return hose and the two pressure
lines from the hydraulic booster (Fig. 49).(7) Remove the booster push rod clip, washer and
rod remove from the brake pedal.
(8) Remove the mounting nuts from the hydraulic
booster and remove the booster.INSTALLATION
(1) Install the hydraulic booster and tighten the
mounting nuts to 28 N´m (21 ft. lbs.).
(2) Install the booster push rod, washer and clip
onto the brake pedal.
(3) Install the master cylinder on the mounting
studs. and tighten the mounting nuts to 23 N´m (17
ft. lbs.).
(4) Install the brake lines to the master cylinder
and tighten to 19-200 N´m (170-200 in. lbs.).
(5) Install the hydraulic booster line bracket onto
the master cylinder mounting studs.
(6) Install the master cylinder mounting nuts and
tighten to 23 N´m (17 ft. lbs.).
Fig. 49 HYDRO-BOOST UNIT
1 - INLET HOSE
2 - HYDRO-BOOST UNIT
3 - MASTER CYLINDER UNIT
4 - RETURN HOSE
5 - OUTLET HOSE
DRBRAKES - BASE 5 - 27
HYDRO-BOOST BRAKE BOOSTER (Continued)
Page 289 of 2895

DESCRIPTIONÐCOOLING SYSTEM FLOW -
5.9L DIESEL
The diesel engine cooling system consists of :
²Cross-flow radiator
²Belt driven water pump
²Belt driven mechanical cooling fan
²Electronic viscous fan drive
²Fan shroud
²Radiator pressure cap²Vertically mounted thermostat
²Coolant reserve/recovery system
²Transmission oil cooler
²Coolant
Coolant flow circuits for the 5.9L diesel engine are
shown in (Fig. 3).
Fig. 1 Engine Cooling System Flow - 3.7L/4.7L
1 - LH CYL. HEAD
2 - BLEED
3 - THERMOSTAT LOCATION
4 - RH CYL. HEAD
5 - RH BANK CYL. BLOCK6 - LH BANK CYL. BLOCK
7 - COOLANT TEMP. SENSOR
8 - FROM HEATER CORE
9 - TO HEATER CORE
7 - 2 COOLINGDR
COOLING (Continued)
Page 294 of 2895

WARNING: DO NOT REMOVE CYLINDER BLOCK
DRAIN PLUGS OR LOOSEN RADIATOR DRAIN-
COCK WITH SYSTEM HOT AND UNDER PRESSURE.
SERIOUS BURNS FROM COOLANT CAN OCCUR.
Drain sufficient coolant to allow thermostat
removal. (Refer to 7 - COOLING/ENGINE/ENGINE
COOLANT THERMOSTAT - REMOVAL). Remove
accessory drive belt (Refer to 7 - COOLING/ACCES-
SORY DRIVE/DRIVE BELTS - REMOVAL).
Add coolant to radiator to bring level to within 6.3
mm (1/4 in) of the top of the thermostat housing.CAUTION: Avoid overheating. Do not operate
engine for an excessive period of time. Open drain-
cock immediately after test to eliminate boil over.
Start engine and accelerate rapidly three times, to
approximately 3000 rpm while observing coolant. If
internal engine combustion gases are leaking into
cooling system, bubbles will appear in coolant. If bub-
bles do not appear, internal combustion gas leakage
is not present.
DIAGNOSIS AND TESTING - COOLING SYSTEM
DIESEL ENGINE
COOLING SYSTEM DIAGNOSISÐDIESEL ENGINE
CONDITION POSSIBLE CAUSES CORRECTION
TEMPERATURE GAUGE READS
LOWNOTE:
Information on dash cluster is
displayed based on broadcast data
from ECM. DTC will be set for
engine sensor circuit concern.1. Vehicle is equipped with a heavy
duty cooling system.1. None. System operating normally.
2. Thermostat stuck open 2. Inspect and test thermostat.
3. Coolant level low. 3. Fill cooling system. (Refer to 7 -
COOLING - STANDARD
PROCEDURE)
4. Temperature gauge not
functioning correctly.4. Check cluster (Refer to 8 -
ELECTRICAL/INSTRUMENT
CLUSTER - DIAGNOSIS AND
TESTING)
DRCOOLING 7 - 7
COOLING (Continued)
Page 295 of 2895

CONDITION POSSIBLE CAUSES CORRECTION
TEMPERATURE GAUGE READS
HIGH. COOLANT MAY OR MAY
NOT BE LEAKING FROM
SYSTEMNOTE:
Information on dash cluster is
displayed based on broadcast data
from ECM. DTC will be set for
engine sensor circuit concern.1. Vehicle overloaded, high ambient
(outside) temperatures with A/C
turned on, stop and go driving or
prolonged operation at idle speeds.1. Temporary condition, repair not
required. Notify customer of vehicle
operation instructions located in
Owners Manual.
2. Temperature gauge not
functioning correctly.2. Check cluster (Refer to 8 -
ELECTRICAL/INSTRUMENT
CLUSTER - DIAGNOSIS AND
TESTING)
3. Air trapped in cooling system 3. Drain cooling system (Refer to 7 -
COOLING - STANDARD
PROCEDURE) and refill (Refer to 7
- COOLING - STANDARD
PROCEDURE)
4. Radiator cap faulty. 4. Replace radiator cap.
5. Plugged A/C or radiator cooling
fins.5. Clean all debris away from A/C
and radiator cooling fins.
6. Coolant mixture incorrect. 6. Drain cooling system (Refer to 7 -
COOLING - STANDARD
PROCEDURE) refill with correct
mixture (Refer to 7 - COOLING -
STANDARD PROCEDURE).
7. Thermostat stuck shut. 7. Inspect and test thermostat.
Replace thermostat if necessary.
8. Bug screen or winter front being
used.8. Remove bug screen or winter
front.
9. Electronically controlled viscous
fan drive not operating properly.9. Check viscous fan (Refer to 7 -
COOLING/ENGINE/FAN DRIVE
VISCOUS CLUTCH - DIAGNOSIS
AND TESTING)
10. Cylinder head gasket leaking. 10. Check for leaking head gaskets
(Refer to 7 - COOLING -
DIAGNOSIS AND TESTING).
11. Heater core leaking. 11. Replace heater core.
12. Cooling system hoses leaking. 12. Tighten clamps or Replace
hoses.
13. Brakes dragging. 13. Check brakes. (Refer to 5 -
BRAKES/HYDRAULIC/
MECHANICAL - DIAGNOSIS AND
TESTING)
14. Accessory drive belt. 14. Inspect. Replace as necessary.
15. Water Pump. 15. Inspect and replace as
necessary.
7 - 8 COOLINGDR
COOLING (Continued)
Page 297 of 2895

CONDITION POSSIBLE CAUSES CORRECTION
INADEQUATE AIR CONDITIONER
PERFORMANCE (COOLING
SYSTEM SUSPECTED)1. Radiator and/or A/C condenser
air flow obstructed.1. Remove obstruction and/or clean.
2. Electronically controlled viscous
fan drive not working.2. Check fan drive. (Refer to 7 -
COOLING/ENGINE/FAN DRIVE
VISCOUS CLUTCH - DIAGNOSIS
AND TESTING)
3. Air seals around radiator
damaged or missing.3. Inspect air seals, repair or
replace as necessary.
INADEQUATE HEATER
PERFORMANCE. GAUGE MAY OR
MAY NOT READ LOW.1. Heavy duty cooling system, and
cooler ambient temperatures.1. None. Normal condition.
2. Obstruction in heater hoses. 2. Remove hoses, remove
obstruction.
3. Electronically controlled viscous
fan stuck onCheck fan drive. (Refer to 7 -
COOLING/ENGINE/FAN DRIVE
VISCOUS CLUTCH - DIAGNOSIS
AND TESTING)
4. Water pump damaged. 4. Replace water pump.
HEAT ODOR 1. Damaged or missing drive line
heat shields.1. Repair or replace damaged or
missing heat shields.
2. Electronically controlled viscous
fan drive damaged.2. Check thermal viscous fan drive.
(Refer to 7 - COOLING/ENGINE/
FAN DRIVE VISCOUS CLUTCH -
DIAGNOSIS AND TESTING)
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.RECENT SERVICE OR ACCIDENT REPAIR:
Determine if any recent service has been per-
formed on vehicle that may effect the 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).
²Service to electrically controlled viscous fan
clutch
NOTE: If investigation reveals none of the previous
items as a cause for an engine overheating com-
plaint, refer to COOLING SYSTEM DIAGNOSIS
CHART BELOW.
These charts are to be used as a quick-reference
only. Refer to COOLING SYSTEM DIAGNOSIS
CHART
7 - 10 COOLINGDR
COOLING (Continued)
Page 301 of 2895

CONDITION POSSIBLE CAUSES CORRECTION
Temperature gauge reading is
inconsistent (flucttuates, cycles
or is erratic)1. During cold weather
operation, with the heater blower
in the high position, the gauge
reading may drop slightly.1. A normal condition. No correction
necessary.
2. Temperature gauge or engine
mounted gauge sensor defective
or shorted. Also, corroded or
loose wiring in this circuit.2. Check operation of gauge and repair if
necessary. (Refer to 8 - ELECTRICAL/
INSTRUMENT CLUSTER - DIAGNOSIS
AND TESTING).
3. Gauge reading rises when
vehicle is brought to a stop after
heavy use (engine still running)3. A normal condition. No correction is
necessary. Gauge should return to normal
range after vehicle is driven.
4. Gauge reading high after
re-starting a warmed up (hot)
engine.4. A normal condition. No correction is
necessary. The gauge should return to
normal range after a few minutes of
engine operation.
5. Coolant level low in radiator
(air will build up in the cooling
system causing the thermostat
to open late).5. Check and correct coolant leaks. (Refer
to 7 - COOLING - DIAGNOSIS AND
TESTING).
6. Cylinder head gasket leaking
allowing exhaust gas to enter
cooling system causing a
thermostat to open late.6. (a) Check for cylinder head gasket
leaks. (Refer to 7 - COOLING -
DIAGNOSIS AND TESTING).
(b) Check for coolant in the engine oil.
Inspect for white steam emitting from the
exhaust system. Repair as necessary.
7. Water pump impeller loose on
shaft.7. Check water pump and replace as
necessary. (Refer to 7 - COOLING/
ENGINE/WATER PUMP - REMOVAL).
8. Loose accessory drive belt.
(water pump slipping)8. (Refer to 7 - COOLING/ACCESSORY
DRIVE/DRIVE BELTS - DIAGNOSIS AND
TESTING). Check and correct as
necessary.
9. Air leak on the suction side of
the water pump allows air to
build up in cooling system
causing thermostat to open late.9. Locate leak and repair as necessary.
PRESSURE CAP IS BLOWING
OFF STEAM AND/OR
COOLANT TO COOLANT TANK.
TEMPERATURE GAUGE
READING MAY BE ABOVE
NORMAL BUT NOT HIGH.
COOLANT LEVEL MAY BE
HIGH IN COOLANT RESERVE/
OVERFLOW TANK1. Pressure relief valve in
radiator cap is defective.1. Check condition of radiator cap and cap
seals. (Refer to 7 - COOLING/ENGINE/
RADIATOR PRESSURE CAP -
DIAGNOSIS AND TESTING). Replace cap
as necessary.
COOLANT LOSS TO THE
GROUND WITHOUT
PRESSURE CAP BLOWOFF.
GAUGE READING HIGH OR
HOT1. Coolant leaks in radiator,
cooling system hoses, water
pump or engine.1. Pressure test and repair as necessary.
(Refer to 7 - COOLING - DIAGNOSIS
AND TESTING).
7 - 14 COOLINGDR
COOLING (Continued)
Page 303 of 2895

CONDITION POSSIBLE CAUSES CORRECTION
INADEQUATE HEATER
PERFORMANCE.
THERMOSTAT FAILED IN
OPEN POSITION1. Has a Diagnostic trouble
Code (DTC) been set?1. (Refer to 25 - EMISSIONS CONTROL -
DESCRIPTION) for correct procedures
and replace thermostat if necessary
2. Coolant level low 2. (Refer to 7 - COOLING - DIAGNOSIS
AND TESTING).
3. Obstructions in heater
hose/fittings3. Remove heater hoses at both ends and
check for obstructions
4. Heater hose kinked 4. Locate kinked area and repair as
necessary
5. Water pump is not pumping
water to/through the heater core.
When the engine is fully warmed
up, both heater hoses should be
hot to the touch. If only one of
the hoses is hot, the water
pump may not be operating
correctly or the heater core may
be plugged. Accessory drive belt
may be slipping causing poor
water pump operation.5. (Refer to 7 - COOLING/ENGINE/
WATER PUMP - REMOVAL). If a slipping
belt is detected, (Refer to 7 - COOLING/
ACCESSORY DRIVE/DRIVE BELTS -
DIAGNOSIS AND TESTING). If heater
core obstruction is detected, (Refer to 24 -
HEATING & AIR CONDITIONING/
PLUMBING/HEATER CORE - REMOVAL).
STEAM IS COMING FROM THE
FRONT OF VEHICLE NEAR
THE GRILL AREA WHEN
WEATHER IS WET, ENGINE IS
WARMED UP AND RUNNING,
AND VEHICLE IS STATIONARY.
TEMPERATURE GAUGE IS IN
NORMAL RANGE1. During wet weather, moisture
(snow, ice or rain condensation)
on the radiator will evaporate
when the thermostat opens. This
opening allows heated water
into the radiator. When the
moisture contacts the hot
radiator, steam may be emitted.
This usually occurs in cold
weather with no fan or airflow to
blow it away.1. Occasional steam emitting from this
area is normal. No repair is necessary.
COOLANT COLOR 1. Coolant color is not
necessarily an indication of
adequate corrosion or
temperature protection. Do not
rely on coolant color for
determining condition of coolant.1. (Refer to LUBRICATION &
MAINTENANCE/FLUID TYPES -
DESCRIPTION). Adjust coolant mixture as
necessary.
COOLANT LEVEL CHANGES IN
COOLANT RESERVE/
OVERFLOW TANK.
TEMPERATURE GAUGE IS IN
NORMAL RANGE1. Level changes are to be
expected as coolant volume
fluctuates with engine
temperature. If the level in the
tank was between the FULL and
ADD marks at normal operating
temperature, the level should
return to within that range after
operation at elevated
temperatures.1. A normal condition. No repair is
necessary.
7 - 16 COOLINGDR
COOLING (Continued)
Page 307 of 2895

WARNING: DO NOT REMOVE OR LOOSEN THE
RADIATOR CAP WITH THE COOLING SYSTEM HOT
AND UNDER PRESSURE. SERIOUS BURNS FROM
THE COOLANT OR HIGH PRESSURE STEAM CAN
OCCUR.
For 3.7L / 4.7L/5.9L engines, remove the radiator
cap from the coolant degas bottle to add coolant.
SPECIFICATIONS
TORQUE
DESCRIPTION N´m Ft. In.
Lbs. Lbs.
Automatic Belt Tensioner to
BlockÐBolts 41 30 Ð
Automatic Belt Tensioner
PulleyÐBolt 61 45 Ð
Block HeaterÐBolt 2 Ð 17
Generator/Compressor
Mounting BracketÐBolts
# 1 and 2 54 40 Ð
# 3 40 30 Ð
Fan Shroud to Radiator
MountingÐBolts6Ð55
Radiator to Support - Bolts 8.5 Ð 75
Fan Blade to Viscous Fan
DriveÐBolts24 18 Ð
Idler PulleyÐBolt 54 40 Ð
Thermostat HousingÐBolts
- All Except 5.9L13 Ð 112
Thermostat HousingÐBolts
- 5.9L23 16 Ð
Power Steering Oil Cooler
Ð Bolts6Ð55
Transmission Auxiliary Oil
CoolerÐBolts 6 Ð 55
Transmission Oil Cooler
Tube Nuts31.5 24 Ð
Coolant Bottle Ð Bolts 8.5 Ð 75
Transmission Oil Cooler to
Transmission - 5.9L/46RE -
Tube Nuts 31.5 24 Ð
Transmission Oil Cooler to
Transmission - 3.7L/4.7L/
45RFE - Tube Nuts20 18 Ð
Water PumpÐBolts 24 18 Ð
Water Pump Ð Bolts - 4.7L 58 43 Ð
SPECIFICATIONS -
SPECIFICATIONS
DESCRIPTION SPECIFICATION
3.7/4.7L Engine 15.4L (16.2 qts.)- to the
middle of the cold fill
range
5.7L Engine 15.4L (16.2 qts.)- to the
middle of the cold fill
range
5.9L Engine 15.5L (16.3 qts.)- to the
MIN mark after 3 warm
up, cool down cycles
8.0L Engine 24L (25.3 qts.)
5.9L Diesel Engine 28L (29.5 qts.)
SPECIAL TOOLS
COOLING
Pliers Constant Pressure Hose Clamp - 6094
3/8º Quick Connect Release Tool - 6935
SPANNER WRENCHÐ6958
7 - 20 COOLINGDR
COOLING (Continued)
Page 309 of 2895

ACCESSORY DRIVE
TABLE OF CONTENTS
page page
BELT TENSIONERS - 3.7L / 4.7L
DESCRIPTION.........................22
OPERATION...........................22
REMOVAL.............................22
INSTALLATION.........................23
BELT TENSIONERS - 5.9L
DESCRIPTION.........................23
OPERATION...........................23
REMOVAL.............................23
INSTALLATION.........................24
BELT TENSIONERS - 5.9L DIESEL
DESCRIPTION.........................24
OPERATION...........................24
REMOVAL.............................25
INSTALLATION.........................25DRIVE BELTS - 3.7L / 4.7L
DIAGNOSIS AND TESTING - ACCESSORY
DRIVE BELT.........................25
REMOVAL.............................27
INSTALLATION.........................27
DRIVE BELTS - 5.9L
DIAGNOSIS AND TESTING - ACCESSORY
DRIVE BELT.........................28
REMOVAL.............................30
INSTALLATION.........................31
DRIVE BELTS - 5.9L DIESEL
DIAGNOSIS AND TESTINGÐACCESSORY
DRIVE BELT.........................31
REMOVAL.............................34
INSTALLATION.........................34
BELT TENSIONERS - 3.7L /
4.7L
DESCRIPTION
Correct drive belt tension is required to ensure
optimum performance of the belt driven engine acces-
sories. If specified tension is not maintained, belt
slippage may cause; engine overheating, lack of
power steering assist, loss of air conditioning capac-
ity, reduced generator output rate, and greatly
reduced belt life.
It is not necessary to adjust belt tension on the
3.7L or 4.7L engine. These engines are equipped with
an automatic belt tensioner (Fig. 1). The tensioner
maintains correct belt tension at all times. Due to
use of this belt tensioner, do not attempt to use a belt
tension gauge on 3.7L or 4.7L engines.
OPERATION
The automatic belt tensioner maintains belt ten-
sion by using internal spring pressure, a pivoting
arm and pulley to press against the drive belt.
REMOVAL
On 3.7L and 4.7L engines, the tensioner is
equipped with an indexing tang on back of ten-
sioner and an indexing stop on tensioner hous-
ing. If a new belt is being installed, tang must
be within approximately 24 mm (.94 inches) ofindexing stop. Belt is considered new if it has
been used 15 minutes or less.
If the above specification cannot be met, check for:
²The wrong belt being installed (incorrect length/
width)
²Worn bearings on an engine accessory (A/C com-
pressor, power steering pump, water pump, idler pul-
ley or generator)
²A pulley on an engine accessory being loose
²Misalignment of an engine accessory
²Belt incorrectly routed.
Fig. 1 AUTOMATIC BELT TENSIONER
1 - AUTOMATIC TENSIONER ASSEMBLY
7 - 22 ACCESSORY DRIVEDR