front JEEP CHEROKEE 1994 Service Repair Manual

TRANSMISSION SHIFT PATTERN
The AX 15 shift pattern is shown in Figure 3. First
and second and third and fourth gear ranges are in
line for improved shifting. Fifth and reverse gear
ranges are also in line at the extreme right of the
pattern (Fig. 3).
The AX 15 is equipped with a reverse lockout
mechanism. The shift lever must be moved through
the Neutral detent before making a shift to reverse.
TRANSMISSION LUBRICANT
Recommended lubricant for AX 15 transmissions is
Mopar 75W-90, API Grade GL-5 gear lubricant, or
equivalent.
Correct lubricant refill or top-off level is to the bot-
tom edge of the fill plug hole.
Lubricant capacity is:
²3.10 liters (3.27 qts.) in 4-wheel drive models.
²3.15 liters (3.32 qts.) in 2-wheel drive models.
TRANSMISSION SWITCH AND PLUG LOCATIONS
The fill plug is at the driver side of the gear case
(Fig. 4).
The drain plug and backup light switch are on the
passenger side of the gear case (Fig. 5).
TRANSMISSION GEAR RATIOS
The transmission gear ratios are as follows:
First gear - 3.83:1
Second gear - 2.33:1
Third gear - 1.44:1
Fourth gear - 1.00:1
Fifth gear - 0.79:1
Reverse - 4.22:1
SERVICE DIAGNOSIS
LOW LUBRICANT LEVEL
A low transmission lubricant level is generally the
result of a leak, inadequate lubricant fill, or an in-
correct lubricant level check.
Leaks can occur at the mating surfaces of the gear
case, intermediate plate and adapter or extension
housing, or from the front/rear seals. A suspected
leak could also be the result of an overfill condition.
Leaks at the rear of the extension or adapter hous-
ing will be from the housing oil seals. Leaks at com-
ponent mating surfaces will probably be the result of
inadequate sealer, gaps in the sealer, incorrect bolt
tightening, or use of a non-recommended sealer.
A leak at the front of the transmission will be from
either the front bearing retainer or retainer seal. Lu-
bricant may be seen dripping from the clutch hous-
ing after extended operation. If the leak is severe, it
may also contaminate the clutch disc causing slip,
grab and chatter.
Transmissions filled from air or electrically pow-
ered lubricant containers can be underfilled. This
generally happens when the container delivery mech-
anism is improperly calibrated. Always check the lu-
bricant level after filling to avoid an under fill
condition.
A correct lubricant level check can only be made
when the vehicle is level; use a drive-on hoist to en-
sure this. Also allow the lubricant to settle for a
Fig. 3 AX 15 Shift Pattern
Fig. 4 Fill Plug Location
Fig. 5 Drain Plug And Backup Light Switch Location
JAX 15 MANUAL TRANSMISSION 21 - 33

(9) Reach up and around transmission case and
unseat shift lever dust boot from transmission shift
tower (Fig. 2). Move boot upward on shift lever for
access to lever retainer.
(10) Disengage shift lever as follows:
(a) Reach up and around transmission case and
press shift lever retainer downward with your fin-
gers.
(b) Turn retainer counterclockwise to release it.
(c) Lift lever and retainer out of shift tower (Fig.
2).It is not necessary to remove shift lever
from floorpan boot. Simply leave lever in
place for later installation.
(11) Mark front and rear propeller shafts for in-
stallation alignment (Fig. 3). Then remove both
shafts.
(12) Remove crankshaft position/engine timing sen-
sor (Fig. 4).
(13) Disconnect transmission and transfer case
vent hoses.
(14) Remove slave cylinder from clutch housing.(15) Support transmission-transfer case assembly
with transmission jack. Secure assembly to jack with
safety chains.
(16) Reposition adjustable jack stand under engine.
Be sure to place wood block between jack and oil
pan.
(17) Remove clutch housing brace rod.
(18) Remove clutch housing-to-engine bolts and re-
move transmission-transfer case assembly.
(19) Remove bolts attaching transmission to trans-
fer case and separate components.
(20) Remove release bearing, fork and retainer
clip.
(21) Remove clutch housing from transmission.
TRANSMISSION INSTALLATIONÐAX 15
(1) Install clutch housing on transmission. Tighten
housing bolts to 37 Nzm (27 ft-lbs) torque.
(2) Lubricate contact surfaces of release fork, lever
and pivot ball stud. Then install bearing, fork and
clip in clutch housing.
(3) Mount transmission on transmission jack. Se-
cure transmission with safety chains.
(4) Lightly lubricate pilot bearing and transmis-
sion input shaft splines with Mopar high tempera-
ture grease.
(5) Align transmission input shaft and clutch disc
splines and install transmission.
(6) Install and tighten clutch housing-to-engine
bolts to 38 Nzm (28 ft. lbs.) torque.Be sure housing
is properly seated on engine before tightening
bolts.
(7) Lower transmission no more than 7.6 cm (3 in.)
for access to the shift tower.
(8) Reach up and around the transmission and in-
sert shift lever in shift tower. Press lever retainer
downward and turn it clockwise to lock it in place.
Then install lever dust boot on shift tower.
(9) Connect engine timing sensor.
Fig. 2 Removing/Installing Shift Lever
Fig. 3 Marking Propeller Shaft And Axle Yoke
Fig. 4 Timing Sensor Location
JAX 15 MANUAL TRANSMISSION 21 - 35

(10) Remove jack from under transmission and
mount transfer case on jack.
(11) Align transfer case and transmission shafts
and install transfer case. Tighten transfer case-to-
transmission nuts/bolts to 35 Nzm (26 ft. lbs.) torque.
(12) Move jack stand from under engine and repo-
sition it under transmission. Then remove transmis-
sion jack.
(13) Connect transfer case vacuum hoses and link-
age. Check and adjust linkage if necessary.
(14) Connect transmission and transfer case vent
hoses and backup light switch wires.
(15) Install clutch sleeve cylinder.
(16) Connect vehicle speed sensor and wires.
(17) On XJ, install rear crossmember and attach
cushion and bracket. Tighten crossmember-to-frame
bolts to 41 Nzm (30 ft. lbs.) torque. Tighten transmis-
sion-to-rear cushion and bracket bolts/nuts to 45 Nzm
(33 ft. lbs.) torque.
(18) On YJ, install rear cushion and bracket and
skid plate. Tighten attaching bolts/nuts to indicated
torque (Fig. 1).
(19) Align and install front/rear propeller shafts.
Tighten shaft U-joint clamp bolts to 19 Nzm (170 in.
lbs.) torque.
(20) On XJ, install skid plate if removed. Tighten
bolts to 42 Nzm (31 ft. lbs.) torque. Tighten stud nuts
to 17 Nzm (150 in. lbs.) torque.
(21) Top off transmission and transfer lubricant
levels.
(22) Remove supports and lower vehicle.
TRANSMISSION DISASSEMBLY AND OVERHAUL
ADAPTER/EXTENSION HOUSING REMOVAL
(1) Remove release bearing, fork, retainer clip and
clutch housing from transmission. Also remove shift
lever if not previously removed.
(2) On 2-wheel drive models, remove extension
housing seal (Fig. 1).(3) Remove shift tower bolts and remove tower
from adapter or extension housing (Fig. 2).
(4) Remove gasket from shift tower (Fig. 3).
(5) Remove shift arm retainer bolt (Fig. 4).
Fig. 1 Removing Extension Housing Seal
Fig. 2 Shift Tower Removal/Installation
Fig. 3 Shift Tower Gasket Removal/Installation
Fig. 4 Shift Arm Retainer Bolt Removal/Installation
21 - 36 AX 15 MANUAL TRANSMISSIONJ

(16) Loosen adapter/extension housing with rubber
mallet (Fig. 13).
(17) Remove housing after loosening it (Fig. 14)
(18) Remove adapter housing oil seal with pry tool
(Fig. 15).GEAR CASE REMOVAL
(1) Remove bearing retainer bolts and remove re-
tainer (Fig. 16).
(2) Remove retainer oil seal with pry tool (Fig. 17).
(3) Remove input shaft bearing snap ring (Fig. 18).
Fig. 13 Loosening Adapter Housing
Fig. 14 Adapter Housing Removal
Fig. 15 Removing Adapter Housing Seal
Fig. 16 Front Bearing Retainer Removal
Fig. 17 Front Bearing Retainer Seal Location
Fig. 18 Removing Input Shaft Bearing Snap Ring
JAX 15 MANUAL TRANSMISSION 21 - 39

(4) Remove cluster gear front bearing snap ring
(Fig. 19).
(5) Loosen gear case by tapping it away from inter-
mediate plate with rubber mallet (Fig. 20).
(6) Remove gear case from geartrain and interme-
diate plate (Fig. 21).(7) On 2-wheel drive models, remove speedometer
gear snap ring and remove speedometer gear and
spacer from output shaft.
FIFTH GEAR AND SYNCHRO ASSEMBLY
REMOVAL
(1) Remove three lock ball plugs from intermediate
plate (Fig. 22).
(2) Remove three lock ball springs and lock balls
from intermediate plate with pencil magnet (Fig. 23).
Fig. 19 Removing Cluster Gear Front Bearing Snap Ring
Fig. 20 Loosening Gear Case
Fig. 21 Gear Case Removal
Fig. 22 Lock Ball Plug Locations
Fig. 23 Removing/Installing Lock Ball And Spring
21 - 40 AX 15 MANUAL TRANSMISSIONJ

(19) Remove bolts attaching output shaft rear
bearing retainer to intermediate plate (Fig. 38).
(20) Remove rear bearing retainer (Fig. 39).
(21) Remove reverse gear and shaft (Fig. 40).
SHIFT RAIL AND FORK REMOVAL
There are a total of five shift rails in the AX 15
transmission. The 1-2, 3-4, fifth gear and front re-
verse shift rails are shown in Figure 41.
Two shift rails are used for reverse gear range. The
front reverse rail is at the forward side of the inter-
mediate plate (Fig. 41). The short rear reverse rail
and reverse shift head are at the rear side of the in-
termediate plate.
It is not necessary to remove the shift rails if
they do not require service during overhaul.
Fig. 38 Removing Output Shaft Rear Bearing Retainer
BoltsFig. 39 Removing Output Shaft Rear Bearing Retainer
Fig. 40 Removing Reverse Idler Gear And Shaft
Fig. 41 Shift Rail Identification
21 - 44 AX 15 MANUAL TRANSMISSIONJ

put shaft flange is worn. Refer to output shaft
inspection in Cleaning and Inspection section.
(3) Press fifth gear and rear bearing off rear of
output shaft.
(4) Remove thrust washer, pin, and first gear and
bearing (Fig. 62).
(5) Remove first/reverse hub snap ring (Fig. 63).
(6) Remove synchro ring.
(7) Press reverse gear and first/reverse hub off
shaft as assembly.(8) Remove remaining synchro ring and second
gear and bearing (Fig. 63).
(9) Remove snap ring at front of output shaft (Fig.
63).
Fig. 62 Checking Output Shaft Gear Thrust Clearance
Fig. 63 Output Shaft And Gears
Fig. 61 Input Shaft Components
JAX 15 MANUAL TRANSMISSION 21 - 49

(10) Press 3-4 hub and sleeve off output shaft as
assembly (Fig. 63).
(11) Remove synchro ring.
(12) Remove third gear and needle bearing (Fig. 63).
TRANSMISSION CLEANING AND INSPECTION
Clean the transmission components in solvent. Dry
the cases, gears, shift mechanism and shafts with com-
pressed air.Dry the bearings with clean, dry shop
towels only. Never use compressed air on the bear-
ings. This could damage the bearing rollers.
Replace components that are obviously worn,
cracked, chipped or damaged in any way.
Inspect the transmission case. Replace the case if
cracked or porous or if any of the bearing and gear
bores are damaged.
Output Shaft Inspection
Measure thickness of the output shaft flange with
a micrometer (Fig. 64). Minimum allowable flange
thickness is 4.70 mm (0.185 in).
If shaft flange thickness is OK but previously
measured second/third gear thrust clearance
was incorrect (Fig. 62), replace the necessary
gear and needle bearing as an assembly.
Check diameter of the first, second and third gear
bearing surfaces of the output shaft (Fig. 64). Mini-
mum allowable diameters are:
²38.86 mm (1.529 in.) for first gear surface
²46.86 mm (1.844 in.) for second gear surface
²37.86 mm (1.490 in.) for third gear surface
Check output shaft runout with V-blocks and a dial
indicator (Fig. 64). Maximum allowable runout is
0.06 mm (0.0024 in.).
Replace the output shaft if any surface measured
fails to meet stated tolerance.
Cluster Gear Inspection
Inspect the cluster gear teeth. Replace the gear if
any teeth are worn or damaged or if the bearing sur-
faces are damaged.
Check diameter of the cluster gear journal with a
micrometer (Fig. 65). Minimum allowable diameter
is 27.860 mm (1.096 in.).
Check condition of the cluster gear front bearing.
Replace the bearing if worn, noisy, or damaged.
GEAR AND SYNCHRO INSPECTION
Install the synchro rings on their respective gears.
Rotate each ring on the gear and note synchro ac-
tion. Replace any synchro ring that exhibits a lack of
braking action or binds on the gear. Also replace any
ring that is worn or has chipped or broken teeth.
Measure end clearance between the synchro ring
and the gear with a feeler gauge (Fig. 66). Clearance
should be 0.06 mm - 1.6 mm (0.024 - 0.063 in.).Install the needle bearings in the first, second and
third gears. Then install the gears on the output
shaft and check shaft-to-gear clearance with a dial
indicator (Fig. 67).
Fig. 64 Checking Output Shaft Tolerances
Fig. 65 Checking Cluster Gear Journal Diameter
21 - 50 AX 15 MANUAL TRANSMISSIONJ

FRONT BEARING, SEAL AND PIN
INSTALLATION
(1) Press front bearing on input shaft. Then secure
bearing with thickest snap ring that will fit in shaft
groove (Fig. 70).
(2) Press front bearing on cluster gear. Then se-
cure bearing with thickest snap ring that will fit in
ring groove on gear (Fig. 71).
(3) Install new oil seals in front bearing retainer and
adapter housing (Fig. 72). Installation depth for bearing
retainer seal is 10.5 - 11.5 mm (0.414 - 0.453 in.).
(4) Install reverse shaft and shaft retaining pin in
adapter housing. Then install access hole plug with
torx bit (Fig. 73).
Fig. 70 Selecting Input Shaft Front Bearing Snap
Ring
Fig. 71 Selecting Cluster Gear Front Bearing Snap
Ring
Fig. 72 Oil Seal Installation
Fig. 73 Installing Reverse Shaft Pin
21 - 52 AX 15 MANUAL TRANSMISSIONJ

(5) Lubricate reverse shaft and gear components
with Mopar 75W-90 gear lubricant.
OUTPUT SHAFT ASSEMBLY
(1) Lubricate output shaft journals, gears and nee-
dle bearings with Mopar 75W-90 gear lubricant.
(2) Install third gear and needle bearing on shaft
(Fig. 63)
(3) Install synchro ring on third gear (Fig. 63).
(4) Assemble 1-2 and 3-4 synchro hubs and sleeves
(Fig.74).
(5) Install inserts and springs in synchro sleeves.
Position open ends of springs 180É apart as shown
(Fig. 75).
(6) Install 3-4 synchro hub and sleeve on output
shaft. Press hub onto shaft if necessary.
(7) Install 3-4 synchro hub snap ring (Fig. 76). Use
thickest snap ring that will fit in shaft groove.
(8) Verify third gear thrust clearance with feeler
gauge (Fig. 56). Clearance should be 0.10 - 0.25 mm
(0.004 - 0.010 in.).(9) Lubricate remaining output shaft gears and
bearings with gear lubricant.
(10) Install second gear and needle bearing on
shaft (Fig. 78).
(11) Install synchro ring on second gear (Fig. 78).
(12) Assemble first/reverse hub, insert springs, in-
serts, reverse gear and 1-2 sleeve (Fig. 78).Be sure
spring ends are 180É apart. Note that splines in
hub bore are chamfered on one side. Install hub
so chamfered side faces front of output shaft.
(13) Press assembled hub and sleeve on output
shaft.
(14) Install selective snap ring (Fig. 78). Use thick-
est snap ring that will fit in output shaft groove.
(15) Install synchro ring on first gear (Fig. 79).
Fig. 74 Synchro Sleeve And Hub Identification
Fig. 75 Insert Spring Position
Fig. 76 Installing 3-4 Synchro Hub Snap Ring
Fig. 77 Checking Third Gear Clearance
JAX 15 MANUAL TRANSMISSION 21 - 53