
A±598 MANUAL TRANSAXLE
CONTENTS
page page
GENERAL INFORMATION
A-598 MANUAL TRANSAXLE............... 2
A-558 MANUAL TRANSAXLEÐRHD
VEHICLES............................ 2
GEAR RATIOS........................... 3
GEAR RATIOSÐRHD VEHICLES............ 3
GEARSHIFT PATTERN..................... 3
GEARSHIFT PATTERNÐRHD VEHICLES...... 3
SELECTION OF LUBRICANT................ 2
SELECTION OF LUBRICANTÐRHD VEHICLES . 2
SPECIAL ADDITIVES..................... 2
SPECIAL ADDITIVESÐRHD VEHICLES....... 3
TRANSAXLE IDENTIFICATION INFORMATION . . 2
TRANSAXLE IDENTIFICATION
INFORMATIONÐRHD VEHICLES.......... 2
DESCRIPTION AND OPERATION
AXLE SEALS............................ 3
GEARSHIFT LEVERS...................... 3
DIAGNOSIS AND TESTING
CLUTCH PROBLEMS..................... 4
COMMON PROBLEM CAUSES.............. 3
HARD SHIFTING......................... 4
LOW LUBRICANT LEVEL.................. 4
NOISY OPERATION....................... 4
SLIPS OUT OF GEAR..................... 4
SERVICE PROCEDURES
FLUID DRAIN AND FILL................... 4
FLUID DRAIN AND FILLÐRHD VEHICLES.... 4
REMOVAL AND INSTALLATION
A-558 TRANSAXLE ASSEMBLYÐRHD
VEHICLES........................... 16
AXLE SEALS........................... 11
BACK-UP LAMP SWITCH.................. 9
CRANKSHAFT POSITION SENSOR Ð
2.5L VM DIESEL...................... 10
CROSSOVER LEVER..................... 11
GEARSHIFT BOOT....................... 5GEARSHIFT BOOT....................... 5
GEARSHIFT CABLES...................... 5
GEARSHIFT CABLESÐRHD VEHICLES....... 7
GEARSHIFT KNOB....................... 5
GEARSHIFT MECHANISM REPLACEMENT..... 7
GEARSHIFT MECHANISM REPLACEMENTÐ
RHD VEHICLES........................ 8
INPUT SHAFT FRONT BEARING RETAINER . . . 15
INPUT SHAFT SEAL..................... 16
SELECTOR LEVER...................... 11
SHIFT SHAFT SEALS.................... 12
TRANSAXLE........................... 12
VEHICLE SPEED SENSOR DRIVE GEAR...... 9
DISASSEMBLY AND ASSEMBLY
DIFFERENTIAL......................... 39
INPUT SHAFT.......................... 32
INTERMEDIATE SHAFT................... 33
SHIFT COVER.......................... 45
SYNCHRONIZER........................ 43
TRANSAXLE........................... 20
TRANSAXLE CASE...................... 48
CLEANING AND INSPECTION
SYNCHRONIZER........................ 52
TRANSAXLE........................... 52
ADJUSTMENTS
BEARING ADJUSTMENT PROCEDURE....... 56
GEARSHIFT CROSSOVER CABLE........... 52
GEARSHIFT CROSSOVER CABLE........... 55
INTERMEDIATE SHAFT BEARING PRELOAD . . 57
SPECIFICATIONS
A-558 MANUAL TRANSAXLEÐRHD
VEHICLES........................... 59
A-598 (T-750) MANUAL TRANSAXLE....... 59
SPECIAL TOOLS
A-558 MANUAL TRANSAXLEÐRHD
VEHICLES........................... 60
A-598 (T-750) MANUAL TRANSAXLE....... 60
NS/GSA±598 MANUAL TRANSAXLE 21 - 1

GENERAL INFORMATION
A-598 MANUAL TRANSAXLE
Safety goggles should be worn at all times
when working on these transaxles.The A-598
manual transaxle uses SAE 5W-30 engine oil, meet-
ing SG and/or SG-CD qualifications, as the factory
fill lubricant. SAE G5 10W-40 engine oil is a suitable
service fill alternative.
This transaxle combines gear reduction, ratio selec-
tion, and differential functions in one unit. It is
housed in a die-cast aluminum case.
A-558 MANUAL TRANSAXLEÐRHD VEHICLES
Safety goggles should be worn at all times
when working on these transaxles.The A-558
manual transaxle uses SAE 5W-30 engine oil, meet-
ing SG and/or SG-CD qualifications, as the factory
fill lubricant. SAE G5 10W-40 engine oil is a suitable
service fill alternative.
This transaxle combines gear reduction, ratio selec-
tion, and differential functions in one unit. It is
housed in a die-cast aluminum case.
TRANSAXLE IDENTIFICATION INFORMATION
The A-598 transaxle model, assembly number,
build date, and final-drive ratio are stamped on a tag
that is attached to the top of the transaxle (Fig. 1).
The last eight digits of the Vehicle Identification
Number (V.I.N.) are stamped on a raised boss on top
of the clutch housing area.
TRANSAXLE IDENTIFICATION INFORMATIONÐRHD
VEHICLES
The A-558 transaxle model, assembly number,
build date, and final-drive ratio are stamped on a tag
that is attached to the top of the transaxle (Fig. 2).NOTE: Certain transaxle assemblies utilize high-
strength steel in various gears. It is imperative that
the correct transaxle assembly number is utilized
when ordering service parts. Do not remove this
tag, so the information is available for future ser-
vice.
The last eight digits of the Vehicle Identification
Number (V.I.N.) are stamped on a raised boss on top
of the clutch housing area.
SELECTION OF LUBRICANT
The A-598 manual transaxle uses SAE 5W-30
engine oil, meeting SG and/or SG-CD qualifications,
as the factory fill lubricant. G5 SAE 10W-40 engine
oil is a suitable service fill alternative.Hypoid gear
lube, manual transmission fluid, and/or auto-
matic transmission fluid should not be used in
this transaxle.Hard shifting effort, bearing, gear,
and/or synchronizer failure may occur if incorrect
fluid is used.
SELECTION OF LUBRICANTÐRHD VEHICLES
The A-558 manual transaxle uses SAE 5W-30
engine oil, meeting SG and/or SG-CD qualifications,
as the factory fill lubricant. G5 SAE 10W-40 engine
oil is a suitable service fill alternative.Hypoid gear
lube, manual transmission fluid, and/or auto-
matic transmission fluid should not be used in
this transaxle.Hard shifting effort, bearing, gear,
and/or synchronizer failure may occur if incorrect
fluid is used.
SPECIAL ADDITIVES
The addition of any fluids to the transaxle, other
than the fluid listed above, is not recommended. An
exception to this policy is the use of special dyes to
aid in detecting fluid leaks. The use of transmission
Fig. 1 Transaxle Identification
Fig. 2 Transaxle Identification
21 - 2 A±598 MANUAL TRANSAXLENS/GS

sealers should be avoided, since they may adversely
affect seals.
SPECIAL ADDITIVESÐRHD VEHICLES
The addition of any fluids to the transaxle, other
than the fluid listed above, is not recommended. An
exception to this policy is the use of special dyes to
aid in detecting fluid leaks. The use of transmission
sealers should be avoided, since they may adversely
affect seals.
GEAR RATIOS
Gear ratios for the 2.4L gasoline engine and 2.5L
Turbo Diesel MTX are as follows:
²1stÐ3.36
²2ndÐ1.90
²3rdÐ1.28
²4thÐ0.92
²5thÐ0.71
²ReverseÐ3.17
Final drive ratio of 3.88 was selected for maximum
performance. All forward gears are synchronized.
Gear ratios for the 2.0L GAS MTX are as follows:
²1stÐ3.69
²2ndÐ2.24
²3rdÐ1.45
²4thÐ1.03
²5thÐ0.81
²ReverseÐ3.17
Final drive ratio of 4.08 was selected for maximum
performance. All forward gears are synchronized.
GEAR RATIOSÐRHD VEHICLES
Gear ratios for the 2.0L GAS MTX are as follows:
²1stÐ3.69
²2ndÐ2.24
²3rdÐ1.45
²4thÐ0.1.03
²5thÐ0.81
²ReverseÐ3.17
Final drive ratio of 4.08 was selected for maximum
performance. All forward gears are synchronized.
GEARSHIFT PATTERN
The A-598 transaxle shift pattern is a H±pattern
(Fig. 3). Overdrive fifth and reverse gears are in±line
and to the right of the first through fourth gear posi-
tions.
GEARSHIFT PATTERNÐRHD VEHICLES
The A-558 transaxle shift pattern is a H±pattern
(Fig. 4). Overdrive fifth and reverse gears are in±line
and to the right of the first through fourth gear posi-
tions.
DESCRIPTION AND OPERATION
GEARSHIFT LEVERS
The gear shift levers at the transaxle are service-
able in the vehicle. The shift levers are different from
each other and do not interchange. The select lever is
not interchangeable with model years earlier than 96
(length is different).
AXLE SEALS
The axle shaft seals are identical for both sides of
the differential and will interchange.
DIAGNOSIS AND TESTING
COMMON PROBLEM CAUSES
The majority of transaxle malfunctions are a result
of:
²Insufficient lubrication
²Incorrect lubricant
²Misassembled or damaged internal components
Fig. 3 A-598 Shift Pattern
Fig. 4 A-558 Shift Pattern
NS/GSA±598 MANUAL TRANSAXLE 21 - 3
GENERAL INFORMATION (Continued)

REMOVAL
(1) Remove electrical connector at crankshaft posi-
tion sensor (Fig. 25).
(2) Remove screw retaining the crankshaft position
sensor to the bellhousing.
(3) Remove the crankshaft position sensor.
INSTALLATION
(1) For installation, reverse removal procedure.
CROSSOVER LEVER
REMOVAL
(1) Remove crossover cable. Refer to Gearshift
Cable removal.
(2) Using a pin punch, remove the crossover roll
pin from lever.
(3) Pull up and remove the crossover lever from
the transaxle crossover shaft.
INSTALLATION
(1) For installation, reverse removal procedure.
Replace the roll pin that was removed with a new
one.
SELECTOR LEVER
REMOVAL
(1) Remove the selector cable. Refer to Gearshift
Cable removal.
(2) Using a pin punch, remove the roll pin from
the lever.
(3) Remove the selector lever from the transaxle
selector shaft
INSTALLATION
(1) For installation, reverse removal procedure.
Replace the roll pin with a new one.
AXLE SEALS
The axle shaft seals are identical for both sides of
the differential and will interchange.
EXTENSION HOUSING AXLE SEAL
REMOVAL
(1) Remove axle shaft. Refer to Group 2, Suspen-
sion and Driveshafts for service procedures.
(2) Insert a flat±blade pry tool into the axle seal
bore (Fig. 26).
(3) Using the pry tool, carefully pop out the seal
taking care not to nick the seal bore.
INSTALLATION
(1) Clean axle shaft seal bore of any excess seal-
ant.
(2) Align axle shaft seal with axle shaft seal bore.
(3) Position axle seal at extension housing.
(4) Using Tool L-4520 and Tool C-4171, tap seal
into position (Fig. 27).
Fig. 25 Crankshaft Position Sensor
Fig. 26 Extension Housing Axle Seal
Fig. 27 Install Seal
NS/GSA±598 MANUAL TRANSAXLE 21 - 11
REMOVAL AND INSTALLATION (Continued)

DIFFERENTIAL BEARING RETAINER AXLE
SEAL
REMOVAL
(1) Remove axle shaft. Refer to Group 2, Suspen-
sion and Driveshafts for service procedures.
(2) Insert a flat±blade pry tool into the axle seal
bore.
(3) Using the pry tool, carefully pop out the seal
taking care not to nick the seal bore.
INSTALLATION
(1) Clean axle shaft seal bore of any excess seal-
ant.
(2) Align axle shaft seal with axle shaft seal bore.
(3) Position axle seal at extension housing.
(4) Using Tool L-4520 and Tool C-4171, tap seal
into position.
SHIFT SHAFT SEALS
It isnotnecessary to remove the shift shaft cover
from the transaxle to service the shift shaft seals.
REMOVAL
(1) Remove the shift lever from the seal that is to
be serviced. Refer to shift lever removal for service
procedure.
(2) Using a pick tool, pry up on the shift shaft seal
and remove seal from bore.
INSTALLATION
(1) Position new shift shaft seal in bore.
(2) Install shift shaft seal into bore using an
appropriate size deep±well socket.
TRANSAXLE
The following items can be serviced without remov-
ing the transaxle from the vehicle:
²Gearshift housing
²5th speed synchronizer
²5th speed gear
²Roller detents and springs
²Speedometer pinion
²Vehicle speed sensor
²Bearing retainer plate.
²All external covers
²Shift shaft seals
²Axle shaft seals
To service any other component of the A-598 tran-
saxle you must remove it from the vehicle.
REMOVAL
(1) Disconnect battery negative cable.
(2) Remove air intake hose. Disconnect air mass
meter connector.
(3) Remove intercooler hose.(4) Remove connectors for back-up lamp (Fig. 28)
and crank position sensor (Fig. 29).
(5) Remove crank position sensor (2.5L VM Diesel
only).
(6) Remove wiring harness bracket at transaxle
(Fig. 30).
(7) Remove crossover and shift selector cables (Fig.
31).
(8) Remove the two top bolts at the rear engine
mount bracket.
(9) Remove bolts securing the coolant reservoir to
the top of the engine. Move the coolant reservoir out
of the way.
(10) Install an engine support chain to the cylinder
head assembly (Fig. 32).
Fig. 28 Back-up Lamp Connector
Fig. 29 Crankshaft Position Sensor
21 - 12 A±598 MANUAL TRANSAXLENS/GS
REMOVAL AND INSTALLATION (Continued)

NOTE: To avoid distortion of the drive plate, bolts
should be tightened a few turns at a time. Use a
crisscross pattern until all bolts are seated. Tighten
modular clutch plate bolts to 74 N´m (55 ft. lbs.).
NOTE: Lower control arm pinch bolts must be
installed with the bolt head rearward of the ball
joint.
(3) Fill transaxle to the proper level with the spec-
ified lubricant.
(4) While the vehicle is elevated slightly, run the
transaxle through all the forward gears. Apply
brakes and shift into reverse. Run the transaxle
through reverse gear.
(5) Check the transaxle for leaks and recheck the
level of the transaxle lubricant.
DISASSEMBLY AND ASSEMBLY
TRANSAXLE
The A-598 transaxle (Fig. 63) is similar to the
A-523, A-568 transaxle with the following exceptions.
The major differences are that the input shaft is sup-
ported by ball and roller bearings and the intermedi-
ate shaft is supported by tapered roller bearings.
Also the front intermediate bearing will not clear the
final drive gear for disassembly or reassembly.
In vehicle service is limited to:
²Shift cover components
²Sealing external joints and seals
²Service of 5th gear set and synchronizer
DISASSEMBLY
(1) Remove engine mount bracket (Fig. 64).
(2) Remove differential bearing retainer (Fig. 65).
(3) Remove extension housing (Fig. 66).
(4) Remove differential cover with soft-faced ham-
mer (Fig. 67).
Fig. 62 Modular Clutch Mounting
Fig. 61 Front Engine Mount (Right Side)
Fig. 63 A-598 Transaxle
21 - 20 A±598 MANUAL TRANSAXLENS/GS
REMOVAL AND INSTALLATION (Continued)

(5) Remove differential assembly (Fig. 68) (Fig.
69).CAUTION: Shift detent springs are located under-
neath shift cover. Remove shift cover carefully.
(6) Remove shift cover (Fig. 70) (Fig. 72).
Fig. 64 Engine Mount Bracket
Fig. 65 Differential Bearing Retainer
Fig. 66 Extension Housing
Fig. 67 Differential Cover
Fig. 68 Differential
Fig. 69 Differential Components
NS/GSA±598 MANUAL TRANSAXLE 21 - 21
DISASSEMBLY AND ASSEMBLY (Continued)

NOTE: The input shaft is serviced as an assembly.
The only serviceable components of the input shaft
are the bearings.To disassemble the intermediate shaft, differential,
synchronizers, or transaxle case, refer to the appro-
priate procedure in this section (Fig. 108).
ASSEMBLY
If the transaxle housing, intermediate shaft, bear-
ing plate, or bearings were replaced, you must adjust
the intermediate shaft bearing preload. To adjust
intermediate shaft preload, refer to Intermediate
Shaft Preload Adjustment.
(1) Install geartrain set.
CAUTION: The 5th gear shift rail has a small inter-
lock pin that is contained within the shift lug and
rail. Use caution when installing shift rail.
(2) Carefully install 5th gear shift rail (Fig. 109)
(Fig. 110).
(3) Install 5th gear shift rail C-clip.
(4) Install reverse shift rail.
(5) Install reverse idler gear (Fig. 111).
Fig. 105 Reverse Shift Rail Removed
Fig. 106 Reposition Shift Rail Lugs
Fig. 107 Geartrain Removal
Fig. 108 Geartrain Components
Fig. 109 5th Gear Shift Rail and Interlock
21 - 28 A±598 MANUAL TRANSAXLENS/GS
DISASSEMBLY AND ASSEMBLY (Continued)