TRANSMISSION SERVICING - A/T
1988 Jeep Cherokee
1988 Automatic Transmission Servicing JEEP
Check fluid level and condition of fluid at each engine oil change. Under normal, light duty operating conditions, change fluid, replace filter and adjust bands every 2 yrs. or 25,000 miles. Under heavy duty service, change fluid, replace filter and adjust bands every 12 months or 12,500 miles.
Check transfer case fluid every 12,000 miles and replace fluid every 30,000 miles.
CHECKING FLUID LEVEL
Park vehicle on a level surface and apply parking brake. With engine idling at normal operating temperature, move transmission selector lever through all gears, ending in "N" ("P" for AW-4 transmission). Check fluid level. Fluid level should be between "FULL" and "ADD ONE PINT" mark on dipstick. Add fluid as needed. DO NOT overfill.
Remove fill plug. Check oil level. If level is not up to fill plug opening, add lubricant until it is.
Both transmissions and transfer cases use DEXRON-II ATF.
NOTE: Transmission and converter capacities are approximate. Fluid level should always be determined by reading on dipstick, rather than amount of fluid added.
TRANSMISSION REFILL CAPACITIES
Including Converter 8.5 qts . (8.0L)
Without Converter 4.3 qts. (4.0L)
TRANSFER CASE REFILL CAPACITIES
Model 207 4.5 pts. (2.1L)
Model 208 6.0 pts. (2.8L)
Model 228 7.0 pts. (3.3L)
Model 229 6.0 pts. (3.8L)
DRAINING & REFILLING
oil pan bolts, tap pan to break it loose and allow
fluid to drain. Remove pan. Install new filter on bottom of valve
body and tighten retaining screws. Install new "O" ring on fluid
pick-up pipe (if needed). Clean oil pan and install with new gasket.
transmission with fluid. Start engine and allow to
run at curb idle for a few minutes. With vehicle on level surface,
engine idling and parking brake applied, move shift selector lever
through all gear ranges, ending in "N" ("P" for AW-4 transmission).
Add fluid up to "ADD ONE PINT" mark on dipstick.
fluid level when transmission reaches normal
operating temperature. Fluid should be between "ADD ONE PINT" and
"FULL" marks on dipstick. Transmission must NOT be overfilled.
Remove drain plug from transfer case. Remove fill plug for easier draining. With fluid fully drained, reinstall drain plug. Fill transfer case to fill plug opening with Dexron II.
NOTE: Bands on the AW-4 (4-speed overdrive) transmission are not adjustable. If slippage occurs, bands must be replaced.
KICKDOWN (FRONT) BAND
kickdown band adjusting screw on left side of case
(near throttle lever shaft). Loosen adjusting screw lock nut and back
off approximately 5 turns. Ensure adjusting screw turns freely in
Adapter (J-24063) and 5/16" square
screw to 36 INCH lbs. (4 N.m). If adapter is not used, tighten screw
to 72 INCH lbs. (8 N.m). Back off adjusting screw. See KICKDOWN
(FRONT) BAND ADJUSTMENT table. Hold adjusting screw in position and tighten lock nut to 35 ft. lbs. (48 N.m).
KICKDOWN (FRONT) BAND ADJUSTMENT
Application (1) Back Off Screw
All Models 2 1/2 Turns
(1) - Tighten screw to 72 INCH lbs. (8 N.m) and back off indicated number of turns.
LOW-REVERSE (REAR) BAND
vehicle, drain transmission fluid and remove oil
pan. Locate adjusting screw on rear servo lever. Loosen adjusting
screw lock nut and back off about 5 turns.
screw to 41 INCH lbs. (4.6 N.m)
and back off
screw at indicated number of turns. See LOW-REVERSE (REAR) BAND
ADJUSTMENT table. Hold adjusting screw in position and tighten lock
nut to 35 ft. lbs. (48 N.m). Install oil pan and fill transmission
LOW-REVERSE (REAR) BAND ADJUSTMENT
Tighten Screw to Back Off
Application INCH Lbs. (N.m) Screw
Model 727 41 (4.6 N.m.) 2 Turns
Model 904 41 (4.6 N.m.) 7 Turns
Model 999 41 (4.6 N.m.) 4 Turns
TRANSMISSION THROTTLE CABLE/LINKAGE
NOTE: A special Idle Speed Actuator (ISA) Exerciser Box Tool is
required to initially set ISA motor and adjust transmission throttle linkage on vehicles with transmission model 999 with 4-cylinder engines.
727 Transmission with 6-Cylinder Engines
throttle control rod spring. Use spring to
hold transmission throttle control lever forward, against stop. Block
choke open and release fast idle cam.
carburetors equipped with throttle operated solenoid
valve, turn key to "ON" position to energize solenoid. Open throttle
halfway to allow solenoid to lock. Return throttle to idle position.
retaining bolt on throttle control adjusting link.
DO NOT remove spring clip or nylon washer. Pull on end of link to
eliminate lash. Tighten link retaining bolt. Reconnect throttle
control rod spring.
727 Transmission with V8 engines
1) Disconnect throttle control rod spring. Use spring to hold transmission throttle valve control lever against forward stop. Block choke open and release fast idle cam.
2) On carburetors equipped with throttle operated solenoid valve, turn key to "ON" position to energize solenoid. Open throttle halfway to allow solenoid to lock. Return throttle to idle position.
3) Loosen retaining bolt on throttle control rod adjusting link. Remove spring clip and slide nylon washer to rear of link. Push on end of link to eliminate lash and tighten retaining bolt. Install nylon washer and spring clip. Reconnect throttle control rod spring.
904 Transmission with 6-Cylinder Engines
cleaner. Hold throttle control lever rearward
against its stop. Block choke plate open and set carburetor linkage
completely off fast idle cam.
throttle control cable by lifting "T" shaped
adjuster clamp with small screwdriver. Move cable outer sheath
forward to remove any cable load on throttle cable bellcrank.
cable by moving cable and sheath rearward until
there is no lash between cable and throttle linkage. Lock cable by
pressing "T" shaped clamp downward until clamp snaps into place.
Install and reconnect any parts removed and/or disconnected.
999 Transmission with 4-Cylinder Engines
vehicle. Using a spring, hook one end on throttle
control lever and other end on torque converter housing. Lower
the ISA motor and connect Exerciser Box to
ISA. Adjustment light should turn off and ready light should turn on.
Press retrack button. Wait until ISA adjusts, ready light goes off
and adjust light goes on.
3) Loosen bolt on throttle control link. Pull on link end to eliminate lash. Tighten adjusting bolt. Press extend button on Exerciser Box. When ISA retracts, release button and disconnect Exerciser Box. Connect ISA wiring and remove spring from throttle control lever. Install and reconnect any parts removed and/or disconnected.
999 Transmission with 6-Cylinder Engines
throttle control rod spring. Use spring to
hold adjusting link in forward position, against nylon washer. Block
choke open and release fast idle cam.
vehicle. Loosen both retaining bolts on adjusting
link clamp. DO NOT remove spring clip or nylon washer. Use a spare
spring to hold transmission throttle lever against forward stop.
adjusting link to eliminate lash and pull clamp to
rear so that bolt in rod bottoms in rear of slot in rod. Tighten
forward clamp retaining bolt.
4) Pull throttle control rod to the rear so that bolt in rod bottoms in front of slot and tighten rear retaining bolt. Remove spare spring. Lower vehicle and reconnect throttle control rod spring.
AW-4 Transmission with All Engines
ignition off, retract cable self-adjusting mechanism
fully. Press cable button down and push cable plunger inward.
throttle lever to wide open throttle position.
While holding throttle lever in position, allow cable plunger to
extend. When plunger is fully extended, release throttle lever. Cable
is now adjusted.
gearshift lever in "P" position and raise vehicle.
Using a small screwdriver, unlock shift control cable by releasing
U-shaped cable adjuster clamp. Remove cable from mounting bracket.
transmission shift lever rearward until fully
seated into "P" detent. Ensure that driveshaft cannot be rotated.
Snap control cable into cable mounting bracket and replace U-shaped
cable adjuster clamp.
vehicle and verify engine starting. Engine should
start only with shifter in "P" or "N" position.
shift rod trunnion jam nuts at transmission lever.
Remove shift rod-to-bellcrank lock pin. Disengage trunnion and shift
rod. Place selector lever in "P" position and lock steering column.
Move transmission shift lever to full rear Park position.
shift rod trunnion to obtain free pin fit in
bellcrank arm. Tighten jam nuts. On vehicles with shift lever on
column, make sure linkage lash is eliminated by pulling down on shift
rod and pushing up on outer bellcrank when tightening jam nuts.
steering column lock for ease of operation. Ensure
engine starts in "N" or "P", only. If starter engages in any drive
gear, or does not work in "N" or "P", check for proper shift linkage
adjustment or faulty neutral safety switch.
NEUTRAL SAFETY SWITCH
combines functions of neutral safety switch and
back-up light switch. With transmission linkage properly adjusted,
switch should allow starter operation in "P" and "N" only.
switch, remove wire connector and test for
continuity between center pin of switch and case. Continuity should
only exist when transmission is in "P" or "N".
for continuity between 2 outer pins.
should exist with transmission in "R" only. There should be no
continuity between either outer pin and transmission case. If any of
these conditions are not met, the switch should be replaced.
switch, unscrew from case. Move selector lever
to "P" and "N" positions and check that switch operating fingers are
centered in switch opening. Install switch and new seal in case.
Check fluid level and add as needed.