engine oil DODGE RAM 2002 Service User Guide

DIFFERENTIAL
REMOVAL
(1) Raise and support the vehicle.
(2) Remove fill hole plug from the differential
housing cover.
(3) Remove differential housing cover and drain
lubricant from the housing.
(4) Clean the housing cavity with a flushing oil,
light engine oil or lint free cloth.Do not use water,
steam, kerosene or gasoline for cleaning.
(5) Remove axle shafts.
(6) Note the orientation of the installation refer-
ence letters stamped on the bearing caps and hous-
ing machined sealing surface (Fig. 27).
(7) Remove the differential bearing caps.
(8) Position Spreader W-129-B with the tool dowel
pins seated in the locating holes (Fig. 28).
(9) Install the hold down clamps and tighten the
tool turnbuckle finger-tight.
(10) Install a Pilot Stud C-3288-B at the left side
of the differential housing. Attach dial indicator to
housing pilot stud. Load the indicator plunger
against the opposite side of the housing (Fig. 28) and
zero the indicator.
(11) Spread the housing enough to remove the case
from the housing. Measure the distance with the dial
indicator (Fig. 28).CAUTION: Never spread the housing over 0.50 mm
(0.020 in). If housing is over-spread, it could be dis-
torted or damaged.
(12) Remove the dial indicator.
(13) Pry the differential case loose from the hous-
ing. To prevent damage, pivot on housing with the
end of the pry bar against spreader (Fig. 29).
(14) Remove the case from housing. Tag bearing
cups to indicate their location.
Fig. 26 Pinon Rotating Torque
1 -TORQUE WRENCH
2 - PINION YOKE
Fig. 27 BEARING CAP IDENTIFICATION
1 - REFERENCE LETTERS
2 - REFERENCE LETTERS
Fig. 28 SPREAD DIFFERENTIAL HOUSING
1 - SPREADER
2 - DIAL INDICATOR
3 - DIFFERENTIAL
4 - DIFFERENTIAL HOUSING
5 - PILOT STUD
3 - 96 REAR AXLE - 267RBIBR/BE
DIFFERENTIAL (Continued)

(12) Install wheel and tire assemblies and lower
the vehicle.
DIFFERENTIAL
REMOVAL
(1) Raise and support the vehicle.
(2) Remove fill hole plug from the differential
housing cover.
(3) Remove differential housing cover and drain
lubricant from the housing.
(4) Clean the housing cavity with a flushing oil,
light engine oil or lint free cloth.Do not use water,
steam, kerosene or gasoline for cleaning.
(5) Remove axle shafts.
(6) Note the orientation of the installation refer-
ence letters stamped on the bearing caps and hous-
ing machined sealing surface (Fig. 26).
(7) Remove the differential bearing caps.
(8) Position Spreader W-129-B with the tool dowel
pins seated in the locating holes (Fig. 27).
(9) Install the hold down clamps and tighten the
tool turnbuckle finger-tight.
(10) Install a Pilot Stud C-3288-B at the left side
of the differential housing. Attach dial indicator to
housing pilot stud. Load the indicator plunger
against the opposite side of the housing (Fig. 27) and
zero the indicator.
(11) Spread the housing enough to remove the case
from the housing. Measure the distance with the dial
indicator (Fig. 27).
CAUTION: Never spread the housing over 0.50 mm
(0.020 in). If housing is over-spread, it could be dis-
torted or damaged.(12) Remove the dial indicator.
(13) Pry the differential case loose from the hous-
ing. To prevent damage, pivot on housing with the
end of the pry bar against spreader (Fig. 28).
Fig. 26 BEARING CAP IDENTIFICATION
1 - REFERENCE LETTERS
2 - REFERENCE LETTERS
Fig. 27 SPREAD DIFFERENTIAL HOUSING
1 - SPREADER
2 - DIAL INDICATOR
3 - DIFFERENTIAL
4 - DIFFERENTIAL HOUSING
5 - PILOT STUD
Fig. 28 DIFFERENTIAL REMOVAL
1 - DIFFERENTIAL
2-PRYBAR
BR/BEREAR AXLE - 286RBI 3 - 125
PINION SEAL (Continued)

CAUTION: Never use gasoline, kerosene, alcohol,
motor oil, transmission fluid, or any fluid containing
mineral oil to clean the system components. These
fluids damage rubber cups and seals. Use only
fresh brake fluid or Mopar brake cleaner to clean or
flush brake system components. These are the only
cleaning materials recommended. If system contam-
ination is suspected, check the fluid for dirt, discol-
oration, or separation into distinct layers. Also
check the reservoir cap seal for distortion. Drain
and flush the system with new brake fluid if con-
tamination is suspected.
CAUTION: Use Mopar brake fluid, or an equivalent
quality fluid meeting SAE/DOT standards J1703 and
DOT 3. Brake fluid must be clean and free of con-
taminants. Use fresh fluid from sealed containers
only to ensure proper antilock component opera-
tion.
CAUTION: Use Mopar multi-mileage or high temper-
ature grease to lubricate caliper slide surfaces,
drum brake pivot pins, and shoe contact points on
the backing plates. Use multi-mileage grease or GE
661 or Dow 111 silicone grease on caliper slide pins
to ensure proper operation.
DIAGNOSIS AND TESTING - BASE BRAKE
SYSTEM
Base brake components consist of the brake shoes,
calipers, wheel cylinders, brake drums, rotors, brake
lines, master cylinder, booster, and parking brake
components.
Brake diagnosis involves determining if the prob-
lem is related to a mechanical, hydraulic, or vacuum
operated component.
The first diagnosis step is the preliminary check.
PRELIMINARY BRAKE CHECK
(1) Check condition of tires and wheels. Damaged
wheels and worn, damaged, or underinflated tires
can cause pull, shudder, vibration, and a condition
similar to grab.
(2) If complaint was based on noise when braking,
check suspension components. Jounce front and rear
of vehicle and listen for noise that might be caused
by loose, worn or damaged suspension or steering
components.
(3) Inspect brake fluid level and condition. Note
that the brake reservoir fluid level will decrease in
proportion to normal lining wear.Also note that
brake fluid tends to darken over time. This is
normal and should not be mistaken for contam-
ination.(a) If fluid level is abnormally low, look for evi-
dence of leaks at calipers, wheel cylinders, brake
lines, and master cylinder.
(b) If fluid appears contaminated, drain out a
sample to examine. System will have to be flushed
if fluid is separated into layers, or contains a sub-
stance other than brake fluid. The system seals
and cups will also have to be replaced after flush-
ing. Use clean brake fluid to flush the system.
(4) Check parking brake operation. Verify free
movement and full release of cables and pedal. Also
note if vehicle was being operated with parking
brake partially applied.
(5) Check brake pedal operation. Verify that pedal
does not bind and has adequate free play. If pedal
lacks free play, check pedal and power booster for
being loose or for bind condition. Do not road test
until condition is corrected.
(6) Check booster vacuum check valve and hose.
(7) If components checked appear OK, road test
the vehicle.
ROAD TESTING
(1) If complaint involved low brake pedal, pump
pedal and note if it comes back up to normal height.
(2) Check brake pedal response with transmission
in Neutral and engine running. Pedal should remain
firm under constant foot pressure.
(3) During road test, make normal and firm brake
stops in 25-40 mph range. Note faulty brake opera-
tion such as low pedal, hard pedal, fade, pedal pulsa-
tion, pull, grab, drag, noise, etc.
(4) Attempt to stop the vehicle with the parking
brake only and note grab, drag, noise, etc.
PEDAL FALLS AWAY
A brake pedal that falls away under steady foot
pressure is generally the result of a system leak. The
leak point could be at a brake line, fitting, hose, or
caliper/wheel cylinder. If leakage is severe, fluid will
be evident at or around the leaking component.
Internal leakage (seal by-pass) in the master cylin-
der caused by worn or damaged piston cups, may
also be the problem cause.
An internal leak in the ABS or RWAL system may
also be the problem with no physical evidence.
LOW PEDAL
If a low pedal is experienced, pump the pedal sev-
eral times. If the pedal comes back up, worn linings,
rotors, drums, or rear brakes out of adjustment are
the most likely causes. The proper course of action is
to inspect and replace all worn component and make
the proper adjustments.
BR/BEBRAKES - BASE 5 - 5
HYDRAULIC/MECHANICAL (Continued)

mile or two. However, if the lining is both soaked and
dirt contaminated, cleaning and/or replacement will
be necessary.
BRAKE LINING CONTAMINATION
Brake lining contamination is mostly a product of
leaking calipers or wheel cylinders, worn seals, driv-
ing through deep water puddles, or lining that has
become covered with grease and grit during repair.
Contaminated lining should be replaced to avoid fur-
ther brake problems.
WHEEL AND TIRE PROBLEMS
Some conditions attributed to brake components
may actually be caused by a wheel or tire problem.
A damaged wheel can cause shudder, vibration and
pull. A worn or damaged tire can also cause pull.
Severely worn tires with very little tread left can
produce a grab-like condition as the tire loses and
recovers traction. Flat-spotted tires can cause vibra-
tion and generate shudder during brake operation. A
tire with internal damage such as a severe bruise,
cut, or ply separation can cause pull and vibration.
BRAKE NOISES
Some brake noise is common with rear drum
brakes and on some disc brakes during the first few
stops after a vehicle has been parked overnight or
stored. This is primarily due to the formation of trace
corrosion (light rust) on metal surfaces. This light
corrosion is typically cleared from the metal surfaces
after a few brake applications causing the noise to
subside.
BRAKE SQUEAK/SQUEAL
Brake squeak or squeal may be due to linings that
are wet or contaminated with brake fluid, grease, or
oil. Glazed linings and rotors with hard spots can
also contribute to squeak. Dirt and foreign material
embedded in the brake lining will also cause squeak/
squeal.
A very loud squeak or squeal is frequently a sign of
severely worn brake lining. If the lining has worn
through to the brake shoes in spots, metal-to-metal
contact occurs. If the condition is allowed to continue,
rotors and drums can become so scored that replace-
ment is necessary.
BRAKE CHATTER
Brake chatter is usually caused by loose or worn
components, or glazed/burnt lining. Rotors with hard
spots can also contribute to chatter. Additional causes
of chatter are out-of-tolerance rotors, brake lining not
securely attached to the shoes, loose wheel bearings
and contaminated brake lining.THUMP/CLUNK NOISE
Thumping or clunk noises during braking are fre-
quentlynotcaused by brake components. In many
cases, such noises are caused by loose or damaged
steering, suspension, or engine components. However,
calipers that bind on the slide surfaces can generate
a thump or clunk noise. In addition, worn out,
improperly adjusted, or improperly assembled rear
brake shoes can also produce a thump noise.
STANDARD PROCEDURE
STANDARD PROCEDURE - MANUAL BLEEDING
Use Mopar brake fluid, or an equivalent quality
fluid meeting SAE J1703-F and DOT 3 standards
only. Use fresh, clean fluid from a sealed container at
all times.
(1) Remove reservoir filler caps and fill reservoir.
(2) If calipers, or wheel cylinders were overhauled,
open all caliper and wheel cylinder bleed screws.
Then close each bleed screw as fluid starts to drip
from it. Top off master cylinder reservoir once more
before proceeding.
(3) Attach one end of bleed hose to bleed screw
and insert opposite end in glass container partially
filled with brake fluid (Fig. 1). Be sure end of bleed
hose is immersed in fluid.
(4)
Open up bleeder, then have a helper press down
the brake pedal. Once the pedal is down close the
bleeder. Repeat bleeding until fluid stream is clear and
free of bubbles. Then move to the next wheel.
Fig. 1 Bleed Hose Setup
1 - BLEED HOSE
2 - FLUID CONTAINER PARTIALLY FILLED WITH FLUID
BR/BEBRAKES - BASE 5 - 7
HYDRAULIC/MECHANICAL (Continued)

(8) Remove the supports and lower the vehicle.
(9) Verify a firm pedal before moving the vehicle.
FLUID
DIAGNOSIS AND TESTING - BRAKE FLUID
CONTAMINATION
Indications of fluid contamination are swollen or
deteriorated rubber parts.
Swollen rubber parts indicate the presence of
petroleum in the brake fluid.
To test for contamination, put a small amount of
drained brake fluid in clear glass jar. If fluid sepa-
rates into layers, there is mineral oil or other fluid
contamination of the brake fluid.
If brake fluid is contaminated, drain and thor-
oughly flush system. Replace master cylinder, propor-
tioning valve, caliper seals, wheel cylinder seals,
Antilock Brakes hydraulic unit and all hydraulic
fluid hoses.
STANDARD PROCEDURE - BRAKE FLUID
LEVEL
Always clean the master cylinder reservoir and
caps before checking fluid level. If not cleaned, dirt
could enter the fluid.
The fluid fill level is indicated on the side of the
master cylinder reservoir (Fig. 19).
The correct fluid level is to the FULL indicator on
the side of the reservoir. If necessary, add fluid to the
proper level.
SPECIFICATIONS
BRAKE FLUID
The brake fluid used in this vehicle must conform
to DOT 3 specifications and SAE J1703 standards.
No other type of brake fluid is recommended or
approved for usage in the vehicle brake system. Use
only Mopar brake fluid or an equivalent from a
tightly sealed container.
CAUTION: Never use reclaimed brake fluid or fluid
from an container which has been left open. An
open container of brake fluid will absorb moisture
from the air and contaminate the fluid.
CAUTION: Never use any type of a petroleum-based
fluid in the brake hydraulic system. Use of such
type fluids will result in seal damage of the vehicle
brake hydraulic system causing a failure of the
vehicle brake system. Petroleum based fluids would
be items such as engine oil, transmission fluid,
power steering fluid, etc.
FLUID RESERVOIR
REMOVAL
(1) Remove reservoir cap and empty fluid into
drain container.
(2) Clamp cylinder body in vise with brass protec-
tive jaws.
(3) Remove pins that retain reservoir to master
cylinder. Use hammer and pin punch to remove pins
(Fig. 20).
(4) Loosen reservoir from grommets with pry tool
(Fig. 21).
(5) Remove reservoir by rocking it to one side and
pulling free of grommets (Fig. 22).
(6) Remove old grommets from cylinder body (Fig.
23).
INSTALLATION
CAUTION: Do not use any type of tool to install the
grommets. Tools may cut, or tear the grommets cre-
ating a leak problem after installation. Install the
grommets using finger pressure only.
(1) Lubricate new grommets with clean brake fluid
and Install new grommets in cylinder body (Fig. 24).
Use finger pressure to install and seat grommets.
(2) Start reservoir in grommets. Then rock reser-
voir back and forth while pressing downward to seat
it in grommets.
Fig. 19 Master Cylinder Fluid Level - Typical
1 - INDICATOR
2 - RESERVOIR
BR/BEBRAKES - BASE 5 - 15
DISC BRAKE CALIPERS (Continued)

OPERATION
When the clutch pedal is depressed, it actuates the
clutch master cylinder. This sends hydraulic pressure
to the clutch slave cylinder. The release fork is then
actuated by the slave cylinder mounted on the trans-
mission housing. The release fork pivots on a ball
stud mounted in the transmission housing and
pushes the release bearing. The release bearing then
depresses the pressure plate spring fingers, thereby
releasing pressure on the clutch disc and allowing
the engine crankshaft to spin independently of the
transmission input shaft (Fig. 2).
WARNING
WARNING: EXERCISE CARE WHEN SERVICING
CLUTCH COMPONENTS. FACTORY INSTALLED
CLUTCH DISCS DO NOT CONTAIN ASBESTOS
FIBERS. DUST AND DIRT ON CLUTCH PARTS MAY
CONTAIN ASBESTOS FIBERS FROM AFTERMAR-
KET COMPONENTS. BREATHING EXCESSIVE CON-
CENTRATIONS OF THESE FIBERS CAN CAUSE
SERIOUS BODILY HARM. WEAR A RESPIRATOR
DURING SERVICE AND NEVER CLEAN CLUTCH
COMPONENTS WITH COMPRESSED AIR OR WITH
A DRY BRUSH. EITHER CLEAN THE COMPONENTSWITH A WATER DAMPENED RAGS OR USE A VAC-
UUM CLEANER SPECIFICALLY DESIGNED FOR
REMOVING ASBESTOS FIBERS AND DUST. DO NOT
CREATE DUST BY SANDING A CLUTCH DISC.
REPLACE THE DISC IF THE FRICTION MATERIAL IS
DAMAGED OR CONTAMINATED. DISPOSE OF ALL
DUST AND DIRT CONTAINING ASBESTOS FIBERS
IN SEALED BAGS OR CONTAINERS. THIS WILL
HELP MINIMIZE EXPOSURE TO YOURSELF AND TO
OTHERS. FOLLOW ALL RECOMMENDED SAFETY
PRACTICES PRESCRIBED BY THE OCCUPATIONAL
SAFETY AND HEALTH ADMINISTRATION (OSHA)
AND THE ENVIRONMENTAL SAFETY AGENCY
(EPA), FOR THE HANDLING AND DISPOSAL OF
PRODUCTS CONTAINING ASBESTOS.
DIAGNOSIS AND TESTING - CLUTCH
A road test and component inspection (Fig. 3) is
recommended to determine a clutch problem.
During a road test, drive the vehicle at normal
speeds. Shift the transmission through all gear
ranges and observe clutch action. If the clutch chat-
ters, grabs, slips or does not release properly, remove
and inspect the clutch components. If the problem is
noise or hard shifting, further diagnosis may be
needed as the transmission or another driveline com-
ponent may be at fault.
CLUTCH CONTAMINATION
Fluid contamination is a frequent cause of clutch
malfunctions. Oil, water or clutch fluid on the clutch
disc and pressure plate surfaces will cause chatter,
slip and grab.
During inspection, note if any components are con-
taminated with oil, hydraulic fluid or water/road
splash.
Oil contamination indicates a leak at either the
rear main seal or transmission input shaft. Oil leak-
age produces a residue of oil on the housing interior
and on the clutch cover and flywheel. Heat buildup
caused by slippage between the cover, disc and fly-
wheel, can sometimes bake the oil residue onto the
components. The glaze-like residue ranges in color
from amber to black.
Road splash contamination means dirt/water is
entering the clutch housing due to loose bolts, hous-
ing cracks or through hydraulic line openings. Driv-
ing through deep water puddles can force water/road
splash into the housing through such openings.
Clutch fluid leaks are usually from damaged slave
cylinder push rod seals.
Fig. 2 CLUTCH OPERATION
1 - FLYWHEEL
2 - PRESSURE PLATE FINGERS
3 - PIVOT POINT
4 - RELEASE BEARING PUSHED IN
5 - CLUTCH DISC ENGAGED
6 - CLUTCH DISC ENGAGED
7 - RELEASE BEARING
6 - 2 CLUTCHBR/BE
CLUTCH (Continued)

IMPROPER RELEASE OR CLUTCH ENGAGEMENT
Clutch release or engagement problems are caused
by wear or damage to one or more clutch compo-
nents. A visual inspection of the release components
will usually reveal the problem part.
Release problems can result in hard shifting and
noise. Items to look for are: leaks at the clutch cylin-
ders and interconnecting line; loose slave cylinder
bolts; worn/loose release fork and pivot stud; dam-
aged release bearing; and a worn clutch disc, or pres-
sure plate.
Normal condensation in vehicles that are stored or
out of service for long periods of time can generate
enough corrosion to make the disc stick to the fly-
wheel, or pressure plate. If this condition is experi-
enced, correction only requires that the disc be
loosened manually through the inspection plate open-
ing.
Engagement problems usually result in slip, chat-
ter/shudder, and noisy operation. The primary causes
are clutch disc contamination; clutch disc wear; mis-
alignment, or distortion; flywheel damage; or a com-
bination of the foregoing. A visual inspection is
required to determine the part actually causing the
problem.
CLUTCH MISALIGNMENT
Clutch components must be in proper alignment
with the crankshaft and transmission input shaft.
Misalignment caused by excessive runout or warpage
of any clutch component will cause grab, chatter and
improper clutch release.
CLUTCH COVER AND DISC RUNOUT
Check the clutch disc before installation. Axial
(face) runout of anewdisc should not exceed 0.50
mm (0.020 in.). Measure runout about 6 mm (1/4 in.)
from the outer edge of the disc facing. Obtain
another disc if runout is excessive.
Check condition of the clutch before installation. A
warped cover or diaphragm spring will cause grab
and incomplete release or engagement. Be careful
when handling the cover and disc. Impact can distort
the cover, diaphragm spring, release fingers and the
hub of the clutch disc.
Use an alignment tool when positioning the disc on
the flywheel. The tool prevents accidental misalign-
ment which could result in cover distortion and disc
damage.
A frequent cause of clutch cover distortion (and
consequent misalignment) is improper bolt tighten-
ing.
DIAGNOSIS CHART
The clutch inspection chart (Fig. 3) outlines items
to be checked before and during clutch installation.
Use the chart as a check list to help avoid overlook-
ing potential problem sources during service opera-
tions.
The diagnosis charts Diagnosis Chart describe
common clutch problems, causes and correction.
Fault conditions are listed at the top of each chart.
Conditions, causes and corrective action are outlined
in the indicated columns.
The charts are provided as a convenient reference
when diagnosing faulty clutch operation.
DIAGNOSIS CHART
CONDITION POSSIBLE CAUSES CORRECTION
Disc facing worn out 1. Normal wear. 1. Replace cover and disc.
2. Driver frequently rides (slips) the
clutch. Results in rapid overheating
and wear.2. Replace cover and disc.
3. Insufficient clutch cover
diaphragm spring tension.3. Replace cover and disc.
Clutch disc facing contaminated with
oil, grease, or clutch fluid.1. Leak at rear main engine seal or
transmission input shaft seal.1. Replace appropriate seal.
2. Excessive amount of grease
applied to the input shaft splines.2. Remove grease and apply the
correct amount of grease.
3. Road splash, water entering
housing.3. Replace clutch disc. Clean clutch
cover and reuse if in good condition.
4. Slave cylinder leaking. 4. Replace hydraulic clutch linkage.
6 - 4 CLUTCHBR/BE
CLUTCH (Continued)

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
Coolant flow circuits for the 5.9L diesel engine are
shown in (Fig. 3).
Fig. 1 Engine Cooling System Flow
1 - HEATER
2 - BYPASS*3 - CROSSFLOW RADIATOR
Fig. 2 Cooling System Components 5.9L Diesel
Engine
1 - RADIATOR CAP
2 - AUXILIARY TRANSMISSION OIL COOLER
3 - CHARGE AIR COOLER
4 - RADIATOR LOWER HOSE
5 - OVERFLOW/RESERVOIR BOTTLE
6 - FAN SHROUD
7 - RADIATOR UPPER HOSE
8 - CONSTANT TENSION CLAMP
7 - 2 COOLINGBR/BE
COOLING (Continued)

hoses, gasket edges and heater. Seal small leak holes
with a Sealer Lubricant (or equivalent). Repair leak
holes and inspect system again with pressure
applied.
Drops Quickly:Indicates that serious leakage is
occurring. Examine system for external leakage. If
leaks are not visible, inspect for internal leakage.
Large radiator leak holes should be repaired by a
reputable radiator repair shop.
INTERNAL LEAKAGE INSPECTION
Remove engine oil pan drain plug and drain a
small amount of engine oil. If coolant is present in
the pan, it will drain first because it is heavier than
oil. An alternative method is to operate engine for a
short period to churn the oil. After this is done,
remove engine dipstick and inspect for water glob-
ules. Also inspect transmission dipstick for water
globules and transmission fluid cooler for leakage.
WARNING: WITH RADIATOR PRESSURE TESTER
TOOL INSTALLED ON RADIATOR, DO NOT ALLOW
PRESSURE TO EXCEED 110 KPA (20 PSI). PRES-
SURE WILL BUILD UP QUICKLY IF A COMBUSTION
LEAK IS PRESENT. TO RELEASE PRESSURE,
ROCK TESTER FROM SIDE TO SIDE. WHEN
REMOVING TESTER, DO NOT TURN TESTER MORE
THAN 1/2 TURN IF SYSTEM IS UNDER PRESSURE.
Operate engine without pressure cap on radiator
until thermostat opens. Attach a Pressure Tester to
filler neck. If pressure builds up quickly it indicates acombustion leak exists. This is usually the result of a
cylinder head gasket leak or crack in engine. Repair
as necessary.
If there is not an immediate pressure increase,
pump the Pressure Tester. Do this until indicated
pressure is within system range of 110 kPa (16 psi).
Fluctuation of gauge pointer indicates compression or
combustion leakage into cooling system.
Because the vehicle is equipped with a catalytic
converter,do notremove spark plug cables or short
out cylinders to isolate compression leak.
If the needle on dial of pressure tester does not
fluctuate, race engine a few times to check for an
abnormal amount of coolant or steam. This would be
emitting from exhaust pipe. Coolant or steam from
exhaust pipe may indicate a faulty cylinder head gas-
ket, cracked engine cylinder block or cylinder head.
A convenient check for exhaust gas leakage into
cooling system is provided by a commercially avail-
able Block Leak Check tool. Follow manufacturers
instructions when using this product.
COMBUSTION LEAKAGE TEST - WITHOUT
PRESSURE TESTER
DO NOT WASTE reusable coolant. If solution is
clean, drain coolant into a clean container for reuse.
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 top of 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.
Fig. 6 Pressure Testing Cooling SystemÐTypical
1 - TYPICAL COOLING SYSTEM PRESSURE TESTER
7 - 6 COOLINGBR/BE
COOLING (Continued)

CONDITION POSSIBLE CAUSES CORRECTION
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).
5. Pressure cap not installed tightly.
If cap is loose, boiling point of
coolant will be lowered. Also refer
to the following Step 6.5. Tighten cap
6. Poor seals at the radiator cap. 6. (a) Check condition of cap and
cap seals. Refer to Radiator Cap.
Replace cap if necessary.
(b) Check condition of radiator filler
neck. If neck is bent or damaged,
replace radiator.
7. Coolant level low in radiator but
not in coolant reserve/overflow
tank. This means the radiator is not
drawing coolant from the coolant
reserve/overflow tank as the engine
cools7. (a) Check condition of radiator
cap and cap seals. Refer to
Radiator Cap in this Group. Replace
cap if necessary.
(b) Check condition of radiator filler
neck. If neck is bent or damaged,
replace radiator.
(c) Check condition of the hose from
the radiator to the coolant tank. It
should fit tight at both ends without
any kinks or tears. Replace hose if
necessary.
(d) Check coolant reserve/overflow
tank and tanks hoses for blockage.
Repair as necessary.
7 - 8 COOLINGBR/BE
COOLING (Continued)