(11) Install the oil baffle. Install the proper shim
combination under the bearing cup.
(12) Install the differential bearing retainer. Seal
the retainer to the housing with MopartSilicone
Rubber Adhesive Sealant. Torque bolts to 28 N´m
(250 in. lbs.).
(13) Using Miller Special Tool L-4436-A and an
inch-pound torque wrench, check the turning torque
of the differential (Fig. 299). The turning torque
should be between 5-18 inch-pounds.
NOTE: If turning torque is too high install a .05mm
(.002 inch) thicker shim. If the turning torque is too
low, install a .05mm (.002 inch) thinner shim. Repeat
until 5-18 inch-pounds of turning torque is
obtained.
CLEANING AND INSPECTION
CLEANING VALVE BODY
Prior to removing any transaxle parts, plug all
openings and clean unit, preferably by steam. Clean-
liness through entire disassembly and assembly can-
not be overemphasized. When disassembling, each
part should be washed in a suitable solvent, then
dried by compressed air.Do not wipe parts with
shop towels.All mating surfaces in the transaxles
are accurately machined; therefore, careful handling
of all parts must be exercised to avoid nicks or burrs.
NOTE: Tag all springs, as they are removed, for
reassembly identification.
ADJUSTMENTS
GEARSHIFT CABLE ADJUSTMENT
Lift and rotate the gearshift hand lever into the
park (P) gate position and remove the ignition key.This confirms the shift lever is in the gated park (P)
position.
After confirming the park gate position, turn the
ignition switch. If the starter will operate, the park
gate position is correct. Move the shift lever into the
neutral (N) position. If the starter will operate in this
position, the linkage is properly adjusted. If the
starter fails to operate in either position, linkage
adjustment is required.
(1) Park the vehicle on level ground and set the
parking brake.
(2) Place the gearshift lever in park (P) gate posi-
tion and remove key.
(3) Loosen the cable adjustment screw at the tran-
saxle operating lever (Fig. 300).
(4) Pull the transaxle operating lever fully forward
to the park detent position.
(5) Release the park brake, then rock the vehicle
to assure it is in park lock. Reset the park brake.
(6) Tighten the cable adjustment screw to 8 N´m
(70 in. lbs.). Gearshift cable should now be properly
adjusted.
(7) Check adjustment by using the preceding pro-
cedure.
Fig. 300 Gearshift Cable Adjustment
21 - 144 TRANSAXLE AND POWER TRANSFER UNITNS
DISASSEMBLY AND ASSEMBLY (Continued)
INSTALLATION
(1) To install, reverse removal procedure. Check
transaxle fluid and P.T.U. fluid and fill to level.
(2) Refer to the Specifications section for the
proper torque specifications.
END COVER SEAL
The Power Transfer Unit must be removed from
the vehicle to perform this operation. Refer to Power
Transfer Unit Removal in this section for procedures.
(1) Remove P.T.U. end cover bolts (Fig. 12).
(2) Gently tap on end cover ears with a hammer to
separate end cover from the case (Fig. 13).
(3) Clean and inspect sealer surfaces.
(4) Apply MopartGasket Maker, Loctite Gasket
Eliminator No.518 or equivalent to sealing surfaces.
(5) Reinstall cover and tighten bolts to 28 N´m
(250 in. lbs.) in the sequence shown in (Fig. 14).
Retighten first bolt after all others are tight.
CAUTION: When end cover is installed be careful
not to damage the P.T.U. Input Shaft Cover Seal.
(6) Reinstall P.T.U. into vehicle.
(7) Check and fill fluids as required.
INPUT SHAFT SEAL
The Power Transfer Unit must be removed from
the vehicle to service this seal. Refer to Power Trans-
fer Unit Removal in this section for procedures.
REMOVAL
(1) Remove P.T.U. end cover bolts (Fig. 15).(2) Gently tap on end cover ears to separate cover
from case (Fig. 16).
(3) Remove ring gear oil trough (Fig. 17).
(4) Remove input shaft and ring gear from case
(Fig. 18).
(5) Use Special Tool No. 7794-A (seal puller) to
remove seal (Fig. 19).
Fig. 12 P.T.U. End Cover Bolts
Fig. 13 End Cover Removal
Fig. 14 Bolt Tightening Sequence
NSTRANSAXLE AND POWER TRANSFER UNIT 21 - 169
REMOVAL AND INSTALLATION (Continued)
²Improper operation
HARD SHIFTING
Hard shifting may be caused by a misadjusted
crossover cable. If hard shifting is accompanied by
gear clash, synchronizer clutch and stop rings or gear
teeth may be worn or damaged.
Misassembled synchronizer components also cause
shifting problems. Incorrectly installed synchronizer
sleeves, struts, or springs can cause shift problems.
NOISY OPERATION
Transaxle noise is most often a result of worn or
damaged components. Chipped, broken gear or syn-
chronizer teeth, and brinnelled, spalled bearings all
cause noise.
Abnormal wear and damage to the internal compo-
nents is frequently the end result of insufficient
lubricant.
SLIPS OUT OF GEAR
Transaxle disengagement may be caused by mis-
aligned or damaged shift components, or worn teeth
on the drive gears or synchronizer components. Incor-
rect assembly also causes gear disengagement.
LOW LUBRICANT LEVEL
Insufficient transaxle lubricant is usually the
result of leaks, or inaccurate fluid level check or refill
method. Leakage is evident by the presence of oil
around the leak point. If leakage is not evident, the
condition is probably the result of an underfill.
If air±powered lubrication equipment is used to fill
a transaxle, be sure the equipment is properly cali-
brated. Equipment out of calibration can lead to an
underfill condition.
The transaxle fill plug is located on the lower left
side of the transaxle end cover. With the vehicle at a
level position, remove the fill plug and check the
level of the lubricant. The lubricant level should be
within 3.175mm (1/8 inch) from the bottom of the fill
hole. If the lubricant level is low, fill the transaxle to
the bottom of the fill hole with SAE 5W-30 engine oil,
meeting SG and/or SG-CD qualifications, as the fac-
tory fill lubricant. SAE GL5 10W-40 engine oil is a
suitable service fill alternative.
CLUTCH PROBLEMS
Worn, damaged, or misaligned clutch components
can cause difficult shifting, gear clash, and noise.
A worn or damaged clutch disc, pressure plate, or
release bearing can cause hard shifting and gear
clash.
SERVICE PROCEDURES
FLUID DRAIN AND FILL
TRANSAXLE FLUID DRAIN
(1) Hoist vehicle.
(2) Install a drain pan underneath the transaxle
drain plug.
(3) Remove the transaxle drain plug. The drain
plug is located on the bottom of the transaxle hous-
ing.
(4) Let fluid drain out till there is just an occa-
sional drip.
(5) Reinstall drain plug. Tighten drain plug to 28
N´m (250 in. lbs.)
TRANSAXLE FLUID FILL
NOTE: All A-598 transaxles are equipped with a fill
plug. The fill plug is located on the end cover side
of the transaxle.
(1) Remove transaxle fill plug
The fluid level should be within 3.175mm (1/8
inch) from the bottom of the transaxle fill hole (vehi-
cle must be level when checking).
(2) Fill transaxle to proper level with SAE 5W-30
engine oil, meeting SG and/or SG-CD qualifications.
G5 SAE 10W-40 engine oil is a suitable service fill
alternative. Dry fill lubricant capacity is approxi-
mately 1.9-2.2 liters (4.0-4.6 pints)..
(3) Wipe the outside of the transaxle if any lubri-
cant spills.
(4) Reinstall transaxle fill plug.
FLUID DRAIN AND FILLÐRHD VEHICLES
TRANSAXLE FLUID DRAIN
(1) Hoist vehicle.
(2) Install a drain pan underneath the transaxle
drain plug.
(3) Remove the transaxle drain plug. The drain
plug is located on the bottom of the transaxle hous-
ing (Fig. 5).
(4) Let fluid drain out till there is just an occa-
sional drip.
(5) Reinstall drain plug. Tighten drain plug to 28
N´m (250 in. lbs.)
TRANSAXLE FLUID FILL
NOTE: All A-558 transaxles are equipped with a fill
plug. The fill plug is located on the end cover side
of the transaxle.
(1) Remove transaxle fill plug
21 - 4 A±598 MANUAL TRANSAXLENS/GS
DIAGNOSIS AND TESTING (Continued)
The fluid level should be within 3.175mm (1/8
inch) from the bottom of the transaxle fill hole (vehi-
cle must be level when checking).
(2) Fill transaxle to proper level with SAE 5W-30
engine oil, meeting SG and/or SG-CD qualifications.
G5 SAE 10W-40 engine oil is a suitable service fill
alternative. Dry fill lubricant capacity is approxi-
mately 1.9-2.2 liters (4.0-4.6 pints).
(3) Wipe the outside of the transaxle if any lubri-
cant spills.
(4) Reinstall transaxle fill plug.
REMOVAL AND INSTALLATION
GEARSHIFT KNOB
REMOVAL
(1) Pull shifter boot down and away from shifter
roll pin.
(2) Pry legs of shift knob away from shift lever roll
pin using a flat blade pry tool (Fig. 6).(3) Remove knob from shifter handle.
INSTALLATION
(1) For installation, reverse removal procedure,
omitting step (2).
GEARSHIFT BOOT
REMOVAL
(1) Remove shifter knob. Refer to gearshift knob
removal.
(2) Pull up on boot until retention clips disengage
from the console and remove (Fig. 7).
INSTALLATION
(1) For installation, reverse removal procedure,
taking care to fully engage the retention clips.
GEARSHIFT BOOT
REMOVAL
(1) Remove shifter knob. Refer to gearshift knob
removal.
(2) Pull up on boot until retention clips disengage
from the console and remove (Fig. 8).
INSTALLATION
(1) For installation, reverse removal procedure,
taking care to fully engage the retention clips.
GEARSHIFT CABLES
REMOVAL
(1) Disconnect battery negative cable.
(2) Remove air cleaner assembly.
(3) Disconnect gearshift cable ends from transaxle
shift levers (Fig. 9) (Fig. 10).
CAUTION: Pry up with equal force on both sides of
shifter cable isolator bushings to avoid damaging
cable isolator bushings.
Fig. 5 Transaxle Drain Plug
Fig. 6 Shifter Knob
Fig. 7 Shifter Boot
NS/GSA±598 MANUAL TRANSAXLE 21 - 5
SERVICE PROCEDURES (Continued)
SPECIAL TOOLS
A-598 (T-750) MANUAL TRANSAXLE
A-558 MANUAL TRANSAXLEÐRHD VEHICLES
A-558 MANUAL TRANSAXLE FLUID FILL
The fluid level should be within 3.175mm (1/8 inch)
from the bottom of the transaxle fill hole (vehicle must
be level when checking).
Fill transaxle to proper level with SAE 5W-30 engine oil,
meeting SG and/or SG-CD qualifications. G5 SAE
10W-40 engine oil is a suitable service fill alternative.
TRANSAXLEMETRIC MEA-
SUREU.S. MEASURE
A-558 1.9-2.2 Liters 2.0-2.3 Quarts
Bearing Splitter 1130
Slide Hammer 3752
Bearing Remover 5066
Gear Holder 6252
Bearing Remover 6786
Bearing Remover 6787
21 - 60 A±598 MANUAL TRANSAXLENS/GS
HEATING AND AIR CONDITIONING
CONTENTS
page page
FRONT HEATING AND AIR CONDITIONING
SYSTEM............................... 1REAR HEATING AND AIR CONDITIONING
SYSTEM.............................. 41
FRONT HEATING AND AIR CONDITIONING SYSTEM
INDEX
page page
GENERAL INFORMATION
INTRODUCTION......................... 2
SAFETY PRECAUTIONS AND WARNINGS...... 2
DESCRIPTION AND OPERATION
A/C PRESSURE TRANSDUCER.............. 2
A/C SERVICE PORTS..................... 2
AIR DISTRIBUTION DUCTS................. 2
COMPRESSOR HIGH-PRESSURE RELIEF
VALVE................................ 3
CONDENSATE DRAIN..................... 3
ENGINE COOLING SYSTEM REQUIREMENTS . . 3
EVAPORATOR PROBE..................... 3
HANDLING TUBING AND FITTINGS........... 3
HVAC CONTROL MODULE................. 4
REAR BLOWER SPEED SWITCH............ 3
SIDE DOOR HEATER A/C OUTLETS.......... 4
SIDE WINDOW DEMISTER................. 4
SYSTEM AIRFLOW....................... 4
SYSTEM OIL LEVEL...................... 5
DIAGNOSIS AND TESTING
A/C PERFORMANCE TEST................ 12
A/C PRESSURE TRANSDUCER............. 12
ACTUATOR CALIBRATION/DIAGNOSTICS AND
COOLDOWN TEST...................... 6
BLOWER MOTOR AND WHEEL ASSEMBLY.... 13
COMPRESSOR CLUTCH/COIL.............. 13
COMPRESSOR NOISE DIAGNOSIS.......... 13
EXPANSION VALVE...................... 13
HEATER PERFORMANCE TEST............ 15
HVAC CONTROL DIAGNOSTIC CONDITIONS . . . 9
SYSTEM CHARGE LEVEL TEST............ 16SERVICE PROCEDURES
CHARGING REFRIGERANT SYSTEM........ 17
EVACUATING REFRIGERANT SYSTEM....... 18
R-134a REFRIGERANT................... 16
STICKING HVAC CONTROL MODULE PUSH
BUTTONS............................ 19
SYSTEM LEAK CHECKING................ 19
THERMOCOUPLE PROBE................. 19
REMOVAL AND INSTALLATION
A/C PRESSURE TRANSDUCER............. 20
A/C SERVICE PORTS.................... 20
BLEND-AIR DOOR ACTUATOR............. 20
BLOWER MOTOR AND WHEEL ASSEMBLY.... 21
BLOWER MOTOR RESISTOR BLOCK........ 21
BLOWER MOTOR WHEEL................. 22
COMPRESSOR CLUTCH/COIL.............. 23
COMPRESSOR......................... 23
CONDENSER ASSEMBLY................. 25
DISCHARGE LINE....................... 26
EVAPORATOR PROBE.................... 27
EXPANSION VALVE...................... 28
FILTER-DRIER ASSEMBLY................. 28
HEATER A/C UNIT HOUSING............... 29
HEATER CORE......................... 30
HEATER HOSES........................ 31
LIQUID LINE........................... 32
MODE DOOR ACTUATOR................. 32
RECIRC DOOR ACTUATOR................ 34
SIDE WINDOW DEMISTER DUCTS.......... 33
SUCTION LINE.......................... 33
DISASSEMBLY AND ASSEMBLY
HEATER A/C UNIT RECONDITION........... 34
NSHEATING AND AIR CONDITIONING 24 - 1
GENERAL INFORMATION
INTRODUCTION
Both the heater and the heater/air conditioning
systems share many of the same components. This
group will deal with both systems together when
component function is common, and separately when
they are not.
For proper operation of the instrument panel con-
trols, refer to the Owner's Manual provided with the
vehicle.
All vehicles are equipped with a common A/C-
heater unit housing assembly. When the vehicle has
only a heater system, the evaporator and recirculat-
ing air door are omitted.
An optional zone control HVAC unit is available.
This unit has dual blend-air doors that can be regu-
lated independently of each other. The temperature
setting can be different from driver's side to passen-
ger side. There is also a rear (aux.) heating and A/C
system available when the vehicle is equipped with
zone control.
SAFETY PRECAUTIONS AND WARNINGS
WARNING: WEAR EYE PROTECTION WHEN SER-
VICING THE AIR CONDITIONING REFRIGERANT
SYSTEM. SERIOUS EYE INJURY CAN RESULT
FROM EYE CONTACT WITH REFRIGERANT. IF EYE
CONTACT IS MADE, SEEK MEDICAL ATTENTION
IMMEDIATELY.
DO NOT EXPOSE REFRIGERANT TO OPEN
FLAME. POISONOUS GAS IS CREATED WHEN
REFRIGERANT IS BURNED. AN ELECTRONIC TYPE
LEAK DETECTOR IS RECOMMENDED.
LARGE AMOUNTS OF REFRIGERANT RELEASED
IN A CLOSED WORK AREA WILL DISPLACE THE
OXYGEN AND CAUSE SUFFOCATION.
THE EVAPORATION RATE OF REFRIGERANT AT
AVERAGE TEMPERATURE AND ALTITUDE IS
EXTREMELY HIGH. AS A RESULT, ANYTHING THAT
COMES IN CONTACT WITH THE REFRIGERANT
WILL FREEZE. ALWAYS PROTECT SKIN OR DELI-
CATE OBJECTS FROM DIRECT CONTACT WITH
REFRIGERANT. R-134a SERVICE EQUIPMENT OR
VEHICLE A/C SYSTEM SHOULD NOT BE PRES-
SURE TESTED OR LEAK TESTED WITH COM-
PRESSED AIR.
SOME MIXTURES OF AIR and R-134a HAVE BEEN
SHOWN TO BE COMBUSTIBLE AT ELEVATED
PRESSURES. THESE MIXTURES ARE POTENTIALLY
DANGEROUS AND MAY RESULT IN FIRE OR
EXPLOSION CAUSING INJURY OR PROPERTY
DAMAGE.
ANTIFREEZE IS AN ETHYLENE GLYCOL BASE
COOLANT AND IS HARMFUL IF SWALLOWED ORINHALED. SEEK MEDICAL ATTENTION IMMEDI-
ATELY IF SWALLOWED OR INHALED. 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 AND PETS.
DO NOT OPEN A COOLING SYSTEM WHEN THE
ENGINE IS AT RUNNING TEMPERATURE. PER-
SONAL INJURY CAN RESULT.
CAUTION: The engine cooling system is designed
to develop internal pressure of 97 to 123 kPa (14 to
18 psi). Allow the vehicle to cool a minimum of 15
minutes before opening the cooling system. Refer
to Group 7, Cooling System.
DESCRIPTION AND OPERATION
AIR DISTRIBUTION DUCTS
The air distribution ducts for the A/C, Heater,
Defroster, and Second Seating Air Distribution are
not serviceable in vehicle. The procedures for service
of these ducts are covered in Group 8E, Instrument
Panel and Gauges.
The only ducts that are serviceable in the vehicle
are the side window demister ducts and the ducts
that feed the front door outlets for the first rear pas-
senger(s) seating. To service the door ducts refer to
Group 23, Body.
A/C PRESSURE TRANSDUCER
The A/C Pressure Transducer (Fig. 1) monitors the
refrigerant gas pressure on the high side of the sys-
tem. The transducer is located on the liquid line. The
pressure transducer turns off the voltage to the com-
pressor clutch coil when refrigerant gas pressure
drops to levels that could damage the compressor.
The transducer also is used to adjust condenser fan
speeds and will turn off compressor at high refriger-
ant pressures. The pressure transducer is a sealed
factory calibrated unit. It must be replaced if defec-
tive. O-ring replacement is required whenever the
pressure transducer is serviced. Be sure to use the
O-ring specified for the transducer.
A/C SERVICE PORTS
The A/C service port valve cores are located within
the A/C lines (Fig. 2). The High Side (Discharge)
valve service port is located on the liquid line near
the right frame rail. The Low Side (Suction) valve
service port is located on the suction line near the
compressor.
24 - 2 HEATING AND AIR CONDITIONINGNS
The High Side service port is a two piece port and
is serviceable. The Low Side service port is not ser-
viceable, the suction line would have to be replaced.
REAR BLOWER SPEED SWITCH
The rear blower speed switch controls the rear
blower with the choice of low and high speeds. When
the switch is on it allows the blower speed switch
located on the rear headliner to control rear blower
speed. This switch will override the rear headliner
blower switch. For operation instructions refer to the
Owner's Manual. The rear blower speed switch is
serviced separately from the A/C control module. For
service procedures, refer to Group 8E, Instrument
Panel And Gauges.
COMPRESSOR HIGH-PRESSURE RELIEF VALVE
The High Pressure Relief Valve prevents damage
to the air conditioning system if excessive pressure
develops. Excessive pressure can be caused by con-
denser air flow blockage, refrigerant overcharge, or
air and moisture in the system.The high pressure relief valve vents only a small
amount of refrigerant necessary to reduce system
pressure and then reseats itself. The majority of the
refrigerant is conserved in the system. The valve is
calibrated to vent at a pressure of 3450 to 4140 kPa
(500 to 600 psi). If a valve has vented a small
amount of refrigerant, it does not necessarily mean
the valve is defective.
The High Pressure Relief Valve is located on the
compressor manifold at the discharge passage.
NOTE: Special effort must be used to keep all
R-134a system components moisture-free. Moisture
in the oil is very difficult to remove and will cause a
reliability problem with the compressor.
CONDENSATE DRAIN
Condensation from the evaporator housing is
drained through the dash panel and on to the
ground. This drain must be kept open to prevent
water from collecting in the bottom of the housing.
If the drain is blocked condensate cannot drain,
causing water to back up and spill into the passenger
compartment. It is normal to see condensate drain-
age below the vehicle.
ENGINE COOLING SYSTEM REQUIREMENTS
To maintain ample temperature levels from the
heating-A/C system, the cooling system must be in
proper working order. Refer to Group 0, Lubrication
and Maintenance or Group 7, Cooling System of this
manual.
The use of a bug screen is not recommended. Any
obstructions forward of the condenser can reduce the
effectiveness of the air conditioning system.
EVAPORATOR PROBE
The Evaporator probe is located on the HVAC. The
probe prevents evaporator freeze-up by signaling the
Powertrain Control Module to cycle the compressor
ON and OFF. The probe monitors the temperature of
the refrigerant after expansion.
The evaporator probe is inserted into the evapora-
tor between the coils. The probe is a sealed unit and
cannot be adjusted or repaired. It must be replaced if
found defective.
HANDLING TUBING AND FITTINGS
Kinks in the refrigerant tubing or sharp bends in
the refrigerant hose lines will greatly reduce the
capacity of the entire system. High pressures are pro-
duced in the system when it is operating. Extreme
care must be exercised to make sure that all connec-
tions are pressure tight. Dirt and moisture can enter
the system when it is opened for repair or replace-
ment of lines or components. The refrigerant oil will
Fig. 1 A/C Pressure Transducer
Fig. 2 Valve Service Ports
NSHEATING AND AIR CONDITIONING 24 - 3
DESCRIPTION AND OPERATION (Continued)