1998 DODGE RAM 1500 air condition

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Introduction
0Lubrication & Maintenance
2Suspension
3Differential & Driveline
5Brakes
6Clutch
7Cooling
8AAudio/Video
8BChime/Buzzer
8EElectronic Control Modules
8FEngine Systems
8GHeated Systems
8HHorn
8IIgnition Control
8JInstrument Cluster
8LLamps
8MMessage Systems
8NPower Systems
8ORestraints
8PSpeed Control
8QVehicle Theft Security
8RWipers/Washers
8TNavigation/Telecommunication
8WWiring
9Engine
11Exhaust System
13Frame & Bumpers
14Fuel System
19Steering
21Transmission and Transfer Case
22Tires/Wheels
23Body
24Heating & Air Conditioning
25Emissions Control
Component and System Index
Service Manual Comment Forms (Rear of Manual)

Oils of the SAE 5W-40 grade number are preferred
when minimum temperatures consistently fall below
-15ÉC. (Fig. 5)
DESCRIPTION - POWER STEERING FLUID
MopartATF +4, Automatic Transmission Fluid is
required in the power steering system. Substitute
fluids can induce power steering system failure.
MopartATF +4, Automatic Transmission 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.ATF+4 also has a unique odor that
may change with age. Consequently, odor and color
cannot be used to indicate the fluid condition or the
need for a fluid change.
DESCRIPTION - ENGINE COOLANT
WARNING: ANTIFREEZE IS AN ETHYLENE GLYCOL
BASE COOLANT AND IS HARMFUL IF SWAL-
LOWED OR INHALED. IF SWALLOWED, DRINK
TWO GLASSES OF WATER AND INDUCE VOMIT-
ING. IF INHALED, MOVE TO FRESH AIR AREA.
SEEK MEDICAL ATTENTION IMMEDIATELY. DO NOT
STORE IN OPEN OR UNMARKED CONTAINERS.
WASH SKIN AND CLOTHING THOROUGHLY AFTER
COMING IN CONTACT WITH ETHYLENE GLYCOL.
KEEP OUT OF REACH OF CHILDREN. DISPOSE OF
GLYCOL BASE COOLANT PROPERLY, CONTACTYOUR DEALER OR GOVERNMENT AGENCY FOR
LOCATION OF COLLECTION CENTER IN YOUR
AREA. DO NOT OPEN A COOLING SYSTEM WHEN
THE ENGINE IS AT OPERATING TEMPERATURE OR
HOT UNDER PRESSURE, PERSONAL INJURY CAN
RESULT. AVOID RADIATOR COOLING FAN WHEN
ENGINE COMPARTMENT RELATED SERVICE IS
PERFORMED, PERSONAL INJURY CAN RESULT.
CAUTION: Use of Propylene Glycol based coolants
is not recommended, as they provide less freeze
protection and less corrosion protection.
The cooling system is designed around the coolant.
The coolant must accept heat from engine metal, in
the cylinder head area near the exhaust valves and
engine block. Then coolant carries the heat to the
radiator where the tube/fin radiator can transfer the
heat to the air.
The use of aluminum cylinder blocks, cylinder
heads, and water pumps requires special corrosion
protection. MopartAntifreeze/Coolant, 5
Year/100,000 Mile Formula (MS-9769), or the equiva-
lent ethylene glycol base coolant with organic corro-
sion inhibitors (called HOAT, for Hybrid Organic
Additive Technology) is recommended. This coolant
offers the best engine cooling without corrosion when
mixed with 50% Ethylene Glycol and 50% distilled
water to obtain a freeze point of -37ÉC (-35ÉF). If it
loses color or becomes contaminated, drain, flush,
and replace with fresh properly mixed coolant solu-
tion.
CAUTION: MoparTAntifreeze/Coolant, 5
Year/100,000 Mile Formula (MS-9769) may not be
mixed with any other type of antifreeze. Mixing of
coolants other than specified (non-HOAT or other
HOAT), may result in engine damage that may not
be covered under the new vehicle warranty, and
decreased corrosion protection.
COOLANT PERFORMANCE
The required ethylene-glycol (antifreeze) and water
mixture depends upon climate and vehicle operating
conditions. The coolant performance of various mix-
tures follows:
Pure Water-Water can absorb more heat than a
mixture of water and ethylene-glycol. This is for pur-
pose of heat transfer only. Water also freezes at a
higher temperature and allows corrosion.
100 percent Ethylene-Glycol-The corrosion
inhibiting additives in ethylene-glycol need the pres-
ence of water to dissolve. Without water, additives
form deposits in system. These act as insulation
causing temperature to rise to as high as 149ÉC
(300ÉF). This temperature is hot enough to melt plas-
Fig. 4 API RATING WRAP FIGURE
Fig. 5 DIESEL OIL VISCOSITY CHART
DRLUBRICATION & MAINTENANCE 0 - 3
FLUID TYPES (Continued)

Miles 102,000 108,000 114,000 120,000
(Kilometers) (163 000) (173 000) (182 000) (192 000)
[Months] [102] [108] [114] [120]
Change engine oil and engine oil filter. X X X X
Drain and refill transfer case fluid (4X4). X
Flush and replace engine coolant, if not done at 60 mos. X
Lubricate outer tie rod ends 2500/3500 (4X4) models
only.XXX X
Inspect brake linings. X
Inspect auto tension drive belt and replace if required
(3.7L/4.7L/5.7L).X³X³
Replace ignition cables.X
Replace engine air cleaner filter.X
Replace spark plugs.X
Inspect PCV Valve, replace as necessary X*
* This maintenance is recommended by the manu-
facture to the owner but is not required to maintain
the emissions warranty.
³ This maintenance is not required if previously
replaced.
Inspection and service should also be performed
anytime a malfunction is observed or suspected.
WARNING: You can be badly injured working on or
around a motor vehicle. Do only that service work
for which you have the knowledge and the right
equipment. If you have any doubt about your ability
to perform a service job, take your vehicle to a
competent mechanic.
MAINTENANCE SCHEDULES Ð 24±VALVE
CUMMINS TURBO DIESEL
There are two maintenance schedules that show
therequiredservice for your vehicle.
First is ScheduleªBº. It is for vehicles that are
operated under the conditions that are listed below
and at the beginning of the schedule.
²Day or night temperatures are below 0É C (32É
F).
²Stop and go driving.
²Extensive engine idling.
²Driving in dusty conditions.
²Short trips of less than 16 km (10 miles).
²More than 50% of your driving is at sustained
high speeds during hot weather, above 32É C (90É F).²Trailer towing.
²Taxi, police, or delivery service (commercial ser-
vice).
²Off-road or desert operation.
NOTE: Most vehicles are operated under the condi-
tions listed for Schedule(B(.
Second is ScheduleªAº. It is for vehicles that are
not operated under any of the conditions listed under
Schedule9B9.
Use the schedule that best describes your driving
conditions. Where time and mileage are listed, follow
the interval that occurs first.
CAUTION: Failure to perform the required mainte-
nance items may result in damage to the vehicle.At Each Stop for Fuel
²Check the engine oil level about 15 minutes
after a fully warmed engine is shut off. Checking the
oil level while the vehicle is on level ground will
improve the accuracy of the oil level reading. Add oil
only when the level is at or below the ADD or MIN
mark.
²Check the windshield washer solvent and add if
required.
²Drain water from the fuel filter.
0 - 12 LUBRICATION & MAINTENANCEDR
MAINTENANCE SCHEDULES (Continued)

Once a Month
²Check tire pressure and look for unusual wear
or damage.
²Inspect the batteries and clean and tighten the
terminals as required.
²Check the fluid levels of coolant reservoir, brake
master cylinder, power steering and transmission
and transfer case (if equipped), add as needed.
²Check Filter MinderŸ. Replace air cleaner
filter element if necessary.
²Check all lights and all other electrical items for
correct operation.
At Each Oil Change
²Change the engine oil filter.
²Inspect the exhaust system.
²Inspect the brake hoses.
²Inspect the CV joints (if equipped) and front sus-
pension components.
²Check the automatic transmission fluid level.
²Check the manual transmission fluid level.
²Check the coolant level, hoses, and clamps.
Tire Rotation
²Rotate the tires every 7,500 miles (12 000 km).
Engine Oil Change Chart Notes
²LTier 1 EPA (250 hp or 305 hp) Engines Only
(see engine data label for your engine type)
²² California LEV (235 hp) Engines Only (see
engine data label for your engine type)
Schedule ªBº
Follow schedule ªBº if you usually operate your
vehicle under one or more of the following conditions.
²Day or night temperatures are below 0É C (32É
F).
²Stop and go driving.
²Extensive engine idling.
²Driving in dusty conditions.
²Short trips of less than 16 km (10 miles).
²More than 50% of your driving is at sustained
high speeds during hot weather, above 32É C (90É F).
²Trailer towing.
²Taxi, police, or delivery service (commercial ser-
vice).
²Off-road or desert operation.
Miles 3,750 7,500 11,250 15,000 18,750
(Kilometers) (6 000) (12 000) (18 000) (24 000) (30 000)
Change engine oil and engine oil filter. X² XL²X²XL²X²
Lubricate outer tie rod ends 2500/3500
(4X4) models only.XX
Inspect water pump weep hole for
blockage.X
Replace fuel filter element. Clean the water
in fuel sensor.X
Change rear axle fluid. X
Change front axle fluid (4X4). X
Inspect brake linings.X
Inspect and adjust parking brake if
necessary.X
DRLUBRICATION & MAINTENANCE 0 - 13
MAINTENANCE SCHEDULES (Continued)

OPERATION
²CASTERis the forward or rearward tilt of the
steering knuckle from vertical. Tilting the top of the
knuckle forward provides less positive caster. Tilting
the top of the knuckle rearward provides more posi-
tive caster. Positive caster promotes directional sta-
bility. This angle enables the front wheels to return
to a straight ahead position after turns (Fig. 1)
²CAMBERis the inward or outward tilt of the
wheel relative to the center of the vehicle. Tilting the
top of the wheel inward provides negative camber.
Tilting the top of the wheel outward provides positive
camber. Incorrect camber will cause wear on the
inside or outside edge of the tire (Fig. 1)
²TOEis the difference between the leading inside
edges and trailing inside edges of the front tires.
Wheel toe position out of specification cause's unsta-
ble steering, uneven tire wear and steering wheel off-
center. The wheel toe position is thefinalfront
wheel alignment adjustment (Fig. 1)
²THRUST ANGLEis the angle of the rear axle
relative to the centerline of the vehicle. Incorrect
thrust angle can cause off-center steering and exces-sive tire wear. This angle is not adjustable, damaged
component(s) must be replaced to correct the thrust
angle (Fig. 1)
DIAGNOSIS AND TESTING - PRE-ALIGNMENT
INSPECTION
Before starting wheel alignment, the following
inspection and necessary corrections must be com-
pleted. Refer to Suspension and Steering System
Diagnosis Chart below for additional information.
(1) Inspect tires for size, air pressure and tread
wear.
(2) Inspect front wheel bearings for wear.
(3) Inspect front wheels for excessive radial or lat-
eral runout and balance.
(4) Inspect ball studs, linkage pivot points and
steering gear for looseness, roughness or binding.
(5) Inspect suspension components for wear and
noise.
(6) On 4x4 vehicles check suspension height (LD
only).
(7) Road test the vehicle.
SUSPENSION AND STEERING SYSTEM DIAGNOSIS
CONDITION POSSIBLE CAUSES CORRECTION
FRONT END NOISE 1. Loose or worn wheel bearing. 1. Replace wheel bearing.
2. Loose or worn steering or
suspension components.2. Tighten or replace components as
necessary.
3. Loose or worn steering or
suspension components.3. Tighten or replace components as
necessary.
EXCESSIVE PLAY IN
STEERING1. Loose or worn wheel bearing. 1. Replace wheel bearing.
2. Loose or worn steering or
suspension components.2. Tighten or replace components as
necessary.
3. Loose or worn steering gear. 3. Replace steering gear.
FRONT WHEELS SHIMMY 1. Loose or worn wheel bearing. 1. Replace wheel bearing.
2. Loose or worn steering or
suspension components.2. Tighten or replace components as
necessary.
3. Tires worn or out of balance. 3. Replace or balance tires.
4. Alignment. 4. Align vehicle to specifications.
VEHICLE INSTABILITY 1. Loose or worn wheel bearing. 1. Replace wheel bearing.
2. Loose or worn steering or
suspension components.2. Tighten or replace components as
necessary.
3. Tire pressure. 3. Adjust tire pressure.
4. Alignment. 4. Align vehicle to specifications.
2 - 2 WHEEL ALIGNMENTDR
WHEEL ALIGNMENT (Continued)

CONDITION POSSIBLE CAUSES CORRECTION
EXCESSIVE STEERING
EFFORT1. Loose or worn steering gear. 1. Replace steering gear.
2. Column coupler binding. 2. Replace coupler.
3. Tire pressure. 3. Adjust tire pressure.
4. Alignment. 4. Align vehicle to specifications.
VEHICLE PULLS TO ONE
SIDE1. Tire pressure. 1. Adjust tire pressure.
2. Tire. 2. Criss-Cross Front Tires.
3. Alignment. 3. Align vehicle to specifications.
4. Loose or worn steering or
suspension components.4. Tighten or replace components as
necessary.
5. Radial tire lead. 5. Rotate or replace tire as necessary.
6. Brake pull. 6. Repair brake as necessary.
7. Weak or broken spring. 7. Replace spring.
8. Ride height (LD) 4WD only. 8. Measure and adjust ride height. (LD
only)
STANDARD PROCEDURE
STANDARD PROCEDURE - HEIGHT
MEASUREMENT - 4WD (LD)
The vehicle suspension height MUST be measured
and adjusted before performing wheel alignment pro-
cedure. Also when front suspension components have
been replaced. This measure must be performed with
the vehicle supporting it's own weight and taken on
both sides of the vehicle.
(1) Inspect tires and set to correct pressure.
(2) Jounce the front of the vehicle.
(3) Measure and record the height from the ground
at the centerline of the rear lower control arm bolt
front tip (Fig. 2).
(4) Measure and record the height from the ground
at the front spindle centerline (Static Load Radius)
(Fig. 2).
(5) Subtract the first measurement from the sec-
ond measurement. The difference between the two
measurement should be 58 mm (2.3 inches) 3mm
(0.12 inches).
(6) If value is greater than 61 mm (2.4 inches),
tighten the torsion bar bolt until the specification is
achieved (Refer to 2 - SUSPENSION/WHEEL
ALIGNMENT - STANDARD PROCEDURE).
(7) If value is less than 55 mm (2.1 inches), loosen
the torsion bar bolt until the specification is achieve-
d,(Refer to 2 - SUSPENSION/WHEEL ALIGNMENT
- STANDARD PROCEDURE).
(8) Repeat the previous steps until the ride height
is within specifications.
STANDARD PROCEDURE - HEIGHT
ADJUSTMENT - 4WD (LD)
The vehicle suspension height MUST be measured
and adjusted before performing wheel alignment pro-
cedure (Refer to 2 - SUSPENSION/WHEEL ALIGN-
MENT - STANDARD PROCEDURE). Also when
front suspension components have been replaced.
This measurement must be performed with the vehi-
cle supporting it's own weight and taken on both
sides of the vehicle.
Fig. 2 HEIGHT MESUREMENT
1 - HEIGHT FROM THE GROUND AT THE FRONT SPINDLE
CENTERLINE (STATIC LOAD RADIUS)
2 - CENTERLINE OF THE REAR LOWER CONTROL ARM BOLT
FRONT TIP
3 - GROUND LINE
DRWHEEL ALIGNMENT 2 - 3
WHEEL ALIGNMENT (Continued)

SHOCK
DIAGNOSIS AND TESTING - SHOCK
A knocking or rattling noise from a shock absorber
may be caused by movement between mounting
bushings and metal brackets or attaching compo-
nents. These noises can usually be stopped by tight-
ening the attaching nuts. If the noise persists,
inspect for damaged and worn bushings, and attach-
ing components. Repair as necessary if any of these
conditions exist.
A squeaking noise from the shock absorber may be
caused by the hydraulic valving and may be intermit-
tent. This condition is not repairable and the shock
absorber must be replaced.
The shock absorbers are not refillable or adjust-
able. If a malfunction occurs, the shock absorber
must be replaced. To test a shock absorber, hold it in
an upright position and force the piston in and out of
the cylinder four or five times. The action throughout
each stroke should be smooth and even.
The shock absorber bushings do not require any
type of lubrication. Do not attempt to stop bushing
noise by lubricating them. Grease and mineral oil-
base lubricants will deteriorate the bushing.
REMOVAL
REMOVAL - 4X2
(1) Raise and support vehicle.
(2) Support the lower control arm outboard end.
(3) Remove the upper shock absorber nut, retainer
and grommet.
(4) Remove the lower nuts and remove the shock
absorber.
REMOVAL - 4X4
(1) Raise and support the vehicle.
(2) Remove the tire and wheel assembly.
(3) Support the lower control arm outboard end.
(4) Remove the upper shock nut and with the insu-
lator and retainer (Fig. 27).
(5) Remove the lower shock bolt (Fig. 27).
(6) Remove the shock
INSTALLATION
INSTALLATION - 4X2
NOTE: Upper shock nut must be replaced or use
Mopar Lock 'N Seal or LoctiteT242 on existing nut.(1) Install the lower retainer and grommet on the
shock absorber stud. Insert the shock absorber
through the frame bracket hole.
(2) Install the lower nuts and tighten the nuts to
28 N´m (21 ft. lbs.).
(3) Install the upper grommet, retainer and new
nut or use Mopar Lock 'N Seal or Loctitet242 on
existing nut, on the shock absorber stud. Tighten nut
to 54 N´m (40 ft. lbs.).
(4) Remove the support from the lower control arm
outboard end.
(5) Lower the vehicle.
INSTALLATION - 4X4
(1) Install the upper part of the shock into the
frame bracket with the insulators and retainers (Fig.
27).
(2) Install the nut and Tighten to 54 N´m (40 ft.
lbs.).
(3) Install the lower part of the shock into the
lower control arm and Tighten the bolt to 135 N´m
(100 ft. lbs.) (Fig. 27).
(4) Remove the support from the lower control arm
outboard end.
(5) Install the tire and wheel assembly (Refer to 22
- TIRES/WHEELS/WHEELS - STANDARD PROCE-
DURE).
(6) Remove the support and lower the vehicle.
STABILIZER BAR
DESCRIPTION
The bar extends across the front underside of the
chassis and connects to the frame crossmember. The
Fig. 27 SHOCK 4X4
1 - INSULATOR & RETAINER
2 - NUT
3 - SHOCK ABSORBER
4 - BOLT
2 - 24 FRONT - INDEPENDENT FRONT SUSPENSIONDR

LOWER SUSPENSION ARM
REMOVAL
(1) Raise and support the vehicle.
(2) Paint or scribe alignment marks on the cam
adjusters and suspension arm for installation refer-
ence (Fig. 22).
(3) Remove the lower suspension arm nut, cam
and cam bolt from the axle.
(4) Remove the nut and bolt from the frame rail
bracket and remove the lower suspension arm (Fig.
22).
INSTALLATION
(1) Position the lower suspension arm at the axle
bracket and frame rail bracket.
(2) Install the rear bolt and finger tighten the nut.
(3) Install the cam bolt, cam and nut in the axle
and align the reference marks.
(4) Remove support and lower the vehicle.
(5) Tighten cam nut at the axle bracket to 217
N´m (160 ft. lbs.). Tighten rear nut at the frame
bracket to 217 N´m (160 ft. lbs.).
SHOCK
DIAGNOSIS AND TESTING - SHOCK
A knocking or rattling noise from a shock absorber
may be caused by movement between mounting
bushings and metal brackets or attaching compo-
nents. These noises can usually be stopped by tight-
ening the attaching nuts. If the noise persists,
inspect for damaged and worn bushings, and attach-
ing components. Repair as necessary if any of these
conditions exist.
A squeaking noise from the shock absorber may be
caused by the hydraulic valving and may be intermit-
tent. This condition is not repairable and the shock
absorber must be replaced.
The shock absorbers are not refillable or adjust-
able. If a malfunction occurs, the shock absorber
must be replaced. To test a shock absorber, hold it in
an upright position and force the piston in and out of
the cylinder four or five times. The action throughout
each stroke should be smooth and even.
The shock absorber bushings do not require any
type of lubrication. Do not attempt to stop bushing
noise by lubricating them. Grease and mineral oil-
base lubricants will deteriorate the bushing.
REMOVAL
(1) Remove the nut, retainer and grommet from
the upper stud in the engine compartment.
(2) Remove three nuts from the upper shock
bracket (Fig. 23).
(3) Remove the lower bolt from the axle bracket
(Fig. 24). Remove the shock absorber from engine
compartment.
INSTALLATION
(1) Position the lower retainer and grommet on the
upper stud. Insert the shock absorber through the
spring from engine compartment.
(2) Install the lower bolt and tighten to 135 N´m
(100 ft. lbs.).
(3) Install the upper shock bracket and three nuts.
Tighten nuts to 75 N´m (55 ft. lbs.).
(4) Install upper grommet and retainer. Install
upper shock nut and tighten to 54 N´m (40 ft. lbs).
Fig. 22 Adjustment Cam
1 - ADJUSTMENT CAM
2 - AXLE BRACKET
3 - BRACKET REINFORCEMENT
4 - LOWER SUSPENSION ARM
2 - 38 FRONT - LINK/COILDR