
7A–3 AUTOMATIC TRANSMISSION (4L30–E)
Service Precaution
WARNING: IF SO EQUIPPED WITH A
SUPPLEMENTAL RESTRAINT SYSTEM (SRS),
REFER TO THE SRS COMPONENT AND WIRING
LOCATION VIEW IN ORDER TO DETERMINE
WHETHER YOU ARE PERFORMING SERVICE ON OR
NEAR THE SRS COMPONENTS OR THE SRS
WIRING. WHEN YOU ARE PERFORMING SERVICE
ON OR NEAR THE SRS COMPONENTS OR THE SRS
WIRING, REFER TO THE SRS SERVICE
INFORMATION. FAILURE TO FOLLOW WARNINGS
COULD RESULT IN POSSIBLE AIR BAG
DEPLOYMENT, PERSONAL INJURY, OR
OTHERWISE UNNEEDED SRS SYSTEM REPAIRS.CAUTION: Always use the correct fastener in the
proper location. When you replace a fastener, use
ONLY the exact part number for that application.
ISUZU will call out those fasteners that require a
replacement after removal. ISUZU will also call out
the fasteners that require thread lockers or thread
sealant. UNLESS OTHERWISE SPECIFIED, do not
use supplemental coatings (Paints, greases, or other
corrosion inhibitors) on threaded fasteners or
fastener joint interfaces. Generally, such coatings
adversely affect the fastener torque and the joint
clamping force, and may damage the fastener. When
you install fasteners, use the correct tightening
sequence and specifications. Following these
instructions can help you avoid damage to parts and
systems.
Construction
A07RS001
Legend
(1) Torque Converter Clutch (TCC)
(2) Fourth Clutch (C4)
(3) Overrun Clutch (OC)
(4) Overdrive Unit
(5) Reverse Clutch (RC)
(6) Second Clutch (C2)(7) Third Clutch (C3)
(8) Ravigneaux Planetary Gear Set
(9) Brake Band (B)
(10) Overdrive Free Wheel (One Way Clutch)
(OFW)
(11) Principle Sprag Assembly (One Way Clutch)
(PFW)

7A–5 AUTOMATIC TRANSMISSION (4L30–E)
Normal Operation Of 2000 4L30–E
Tr a n s m i s s i o n
Torque Converter Clutch (TCC)
Application Conditions:
The TCC is normally applied in 2nd, 3rd and 4th gears
only when all of the following conditions exist:
— The engine coolant temperature is above 70
C
(158
F).
— The brake pedal is released.
— The shift pattern requests TCC apply.
Moreover, TCC is always applied in 2nd, 3rd and 4th
gears when the transmission oil temperature is above
135
C (275F).
This mode should be canceled at 125
C (257F).
ATF Warning Lamp
The ATF warning lamp will be constantly on (not flashing)
if the transmission oil temperature is above 145
C
(293
F).
The ATF warning lamp goes off again when the
transmission oil temperature is below 125
C (257F).
Special Shift Pattern When The Engine Is
Cold:
A special shift pattern is activated when the engine
coolant temperature is below 70
C (158F). (3–4 shifts,
for example, are delayed for small throttle openings and
will occur a few MPH higher.)
Diagnosis
Introduction
The systematic troubleshooting information covered by
this Section offers a practical and systematic approach to
diagnosing 4L30–E transmission, using information that
can be obtained from road tests, electrical diagnosis, oil
pressure checks or noise evaluation.
The key to correcting a complaint is to make use of all of
the available symptoms and logically letting them direct
you to the cause.
When dealing with automatic transmission complaints, it
is best to gather as many symptoms as possible before
making the decision to remove the transmission from the
vehicle.
Frequently, the correction of the complaint does not
require removal of the transmission from the vehicle.
Driver Information
To analyze the problem fill out a complete description of
the owner’s complaint.
Please draw a circle around the right information and
complete the following form. (The next page is an
example of a completed form). You can draw a circle
around many numbers if you are not sure.

7A–10
AUTOMATIC TRANSMISSION (4L30–E)
Checking Transmission Fluid Level
and Condition
Checking fluid level and condition (color and odor) at
regular intervals will provide early diagnosis information
about the transmission. This information may be used to
correct a condition that, if not detected early, could result
in major transmission repairs.
IMPORTANT:When new, automatic transmission fluid
is red in color. As the vehicle is driven, the transmission
fluid will begin to look darker in color. The color may
eventually appear light brown.
A dark brown color with burnt odor may indicate
excessive fluid deterioration and signal a need for fluid
change.
Fluid Level
When adding or changing fluid, use only DEXRON –III.
Refer to Maintenance and Lubrication in General
Information section for maintenance information and
servicing interval.
CAUTION: DO NOT OVERFILL.
Overfilling will cause foaming, loss of fluid, abnor-
mal shifting and possible damage to the transmis-
sion.
1. Park the vehicle on level ground and apply the parking
brake firmly.
2. Check fluid level with engine running at idle.
NOTE: Be sure that transmission fluid temperature is
below 30
C (86F).
3. Move the selector lever through all gear ranges.
4. Move the selector lever to “Park”.
5. Let engine idle for 3 minutes and open the overfill
screw (1).
6. Add released transmission fluid until it flows out over
the overfill screw opening.
7. Let engine idle until a fluid temperature between 32
C
(90
F) and 57C (135F) is reached, then close the
overfill screw (1).
Torque: 38 N
m (3.9 kgꞏm/28 lb ft)
NOTE: To prevent fluid leaks, the overfill screw and oil
drain screws gasket must be replaced each time these
screws are removed.NOTE: Check transmission fluid temperature with scan
tool.
Minimum fluid level
57C (135F)
Maximum fluid level
32C (90F)
242RW003
CAUTION: Do not open overfill screw with engine
stopped.
CAUTION: DO NOT CHECK FLUID LEVEL UNDER
THESE CONDITIONS:
Immediately after driving at sustained highway
speeds.
In heavy city traffic during hot weather.
If vehicle is towing a trailer.
If the vehicle has been operated under these conditions,
shut the engine off and allow the vehicle to “cool” for thirty
(30) minutes. After the cool down period, restart the
vehicle and continue from step 2 above.

7A–13 AUTOMATIC TRANSMISSION (4L30–E)
Mechanical / Hydraulic Diagnosis Symptoms Index
Perform Preliminary Inspection First!
CHART
SYMPTOMS
1NO ENGINE START IN NEUTRAL OR PARK
2NO FORWARD GEARS IN ANY RANGE/NO REVERSE
3NO ENGINE BRAKE IN ANY RANGE
4POOR SHIFTING IN ALL GEARS (ALL HARSH OR ALL SOFT)
5aDELAYS IN DRIVE AND REVERSE
5bDELAYS IN REVERSE ONLY
6DIAGNOSTIC TROUBLE CODE (DTC) P0730
7HARSH 1–2 SHIFT
8HARSH 3–4 SHIFT
9a3–2 DOWNSHIFT COMPLAINT
9bHARSH SHIFT WHEN SHIFTING INTO “D” OR ACCELERATING FROM STOP
9cCOASTDOWN HARSH SHIFT OR CLUNK AT 3–2 DOWNSHIFT
10INTERMITTENT 4TH TO 2ND GEAR DOWNSHIFT AT STEADY SPEED
11ENGINE FLARE AT SHIFTING DURING TURNING ONLY (USUALLY WITH WARM ENGINE)
12ENGINE FLARE DURING 1–2 OR 2–3 SHIFT
13SHUDDER ONLY DURING TORQUE CONVERTER CLUTCH (TCC) APPLYING
14POSSIBLE CAUSES OF TRANSMISSION NOISE
15aPOSSIBLE CAUSES OF LOW LINE PRESSURE
15bPOSSIBLE CAUSES OF HIGH LINE PRESSURE
16POSSIBLE CAUSES OF TRANSMISSION FLUID LEAKS
NOTE: Numbers with parenthesis on the following charts
refer to Parts List at end of this section.
Chart 1: No Engine Start In Neutral Or Park
StepActionYe sNo
1Does engine start when shift lever moved from drive to neutral
mostly in hot condition?
Go to Step 2Go to Step 3
2Does engine start in park at any condition?Re–test vehicleGo to Step 4
3Does engine also not start in neutral when shift lever moved from
park to neutral?
Go to Step 4Go to Step 5
4Check mode switch (63) setting. Readjust if necessary.
Problems fixed?
Re–test vehicleGo to Step 5
5Check start circuit of mode switch (63) open in neutral.
Was open found?Locate and repair
open(s)Replace mode
switch (63)

7A–14
AUTOMATIC TRANSMISSION (4L30–E)
Chart 2: No Forward Gears In Any Range/No Reverse
StepActionYe sNo
1Check line pressure. Refer to Line Pressure Test in this section.
Was line pressure normal?
Go to Step 2
Use Chart 15a:
Possible Causes
of Low Line
Pressure in this
section
21. Check internal linkage:
– Manual linkage (58) not moving manual valve (326).
2. Check for internal mechanical damage:
– Turbine shaft (506) broken loose.
– Overrun roller clutch (516) broken loose.
Was the problem found?
Repair or replace—
Chart 3: No Engine Brake In Any Range
StepActionYe sNo
1Check line pressure. Refer to Line Pressure Test in this section.
Was line pressure normal?
Go to Step 2
Use Chart 15a:
Possible Causes
of Low Line
Pressure in this
section
21. Check for overrun clutch leaks caused by:
– Damaged piston lip (513)
– Check ball defective (504)
2. Check for overrun lockout valve (705) stuck by foreign
material.
3. Check for leaks at turbine shaft (506) caused by:
– Teflon seal rings damaged (508)
– Excessive wear of turbine shaft bearing surfaces.
Was the problem found?
Repair or replace—

7A–16
AUTOMATIC TRANSMISSION (4L30–E)
Chart 6: Diagnostic Trouble Code (DTC) P0730
StepActionYe sNo
1Check line pressure. Refer to Line Pressure Test in this section.
Was line pressure normal?
Go to Step 2
Use Chart 15b:
Possible Causes
of High Line
Pressure in this
section
21. 1st and 2nd gear missing or 3rd and 4th gear missing.
Check appropriate shift valve. If OK replace solenoid.
2. No engine brake in any range (All ranges in Drive and Reverse
are OK).
Check for suspected conditions modifying delays to clutch
apply:
– Overrun clutch seal damaged.
– Excessive overrun clutch piston travel.
– Defective 3–4 accumulator piston.
– Causes of internal leaks.
– Causes of burned clutch plates.
3. 1st and 4th gear missing or 2nd and 3rd gear missing.
Shift solenoid A stuck. Replace shift solenoid A.
4. DTC P0730 is set in D range 1st gear above 3500 rpm.
Go to Step 3.
5. DTC P0730 is set in D range 3rd gear between 55-80 mph.
NOTE: Perform this test within safe and legal limits.
Check for suspected conditions modifying delays to clutch
apply:
– 4th clutch seal damaged.
– Excessive 4th clutch piston travel.
– Defective 3–4 accumulator piston.
– Causes of internal leaks.
– Causes of burned clutch plates.
Was the problem found?
Repair or replace—
3Check 3rd gear in “D” in winter mode.
Does vehicle move?Shift solenoid A
stuck. Replace
shift solenoid A.
Go to Step 4
4Check for suspected conditions modifying delays to clutch apply:
– 2nd clutch seal damaged.
– Excessive 2nd clutch piston travel.
– Defective accumulator piston.
– Causes of internal leaks.
– Check ball missing or out of location in 2nd clutch.
– Seals cut, damaged or missing.
– Gaskets defective.
– Causes of burned clutch plates.
Was the problem found?
Repair or replace—

7A–23 AUTOMATIC TRANSMISSION (4L30–E)
Stall Test
The stall test allows you to check the transmission for
internal abrasion and the one way clutch for slippage.
Torque converter performance can also be evaluated.
The stall test results together with the road test results will
identify transmission components requiring servicing or
adjustment.
Stall Test Procedure:
1. Check the level of the engine coolant, the engine oil,
and the automatic transmission fluid. Replenish if
necessary.
2. Block the wheels and set the parking brake.
3. Connect a tachometer to the engine.
4. Start the engine and allow it to idle until the engine
coolant temperature reaches 70 – 80
C (158 –
176
F).
5. Hold the brake pedal down as far as it will go.
6. Place the selector in the “D” range.
7. Gradually push the accelerator pedal to the floor.
The throttle valve will be fully open.
Note the engine speed at which the tachometer
needle stabilizes.
Stall Speed : 2,100
150 rpm
NOTE: Do not continuously run this test longer than 5
seconds.
8. Release the accelerator pedal.
9. Place the selector in the “N” range.
10. Run the engine at 1,200 rpm for one minute.
This will cool the transmission fluid.
11. Repeat Steps 7 – 10 for the “3”, “2”, “L” and “R”
ranges.
Line Pressure Test
The line pressure test checks oil pump and control valve
pressure regulator valve function. It will also detect oil
leakage.
Line Pressure Test Procedure:
1. Check the level of the engine coolant, the engine oil,
and the automatic transmission fluid.
Replenish if required.
2. Block the wheels and set the parking brake.
3. Remove the pressure detection plug at the left side of
the transmission case.
Set 5–8840–0004–0 pressure gauge and adapter to
the pressure detection plug hole.
241RS001
4. Start the engine and allow it to idle until the engine
coolant temperature reaches 70 – 80
C (158 –
176
F).
5. Hold the brake pedal down as far as it will go.
6. Place the selector in the “D” range.
7. Note the pressure gauge reading with the engine
idling.
8. Gradually push the accelerator pedal to the floor. The
throttle valve will be fully open.
Note the pressure gauge reading with the accelerator
pedal fully depressed.
NOTE: Do not continuously run this test longer than 5
seconds.
9. Release the accelerator pedal.
10. Place the selector in the “N” range.
11. Run the engine at 1,200 rpm for one minute.
This will cool the transmission fluid.
12. Repeat Steps 7 – 11 for the “3”, “2”, “L”, and “R”
ranges.
13. Install a pressure detection plug to the transmission
case, applying recommended thread locking agent
(LOCTITE 242) or its equivalent to thread of plug.
Make sure that thread is cleaned before applying
locking agents.
14. Tighten the pressure detection plug to the specified
torque.
Torque:9–14Nꞏm(0.9–1.4kgꞏm/7–10lbft)

7A–31 AUTOMATIC TRANSMISSION (4L30–E)
NOTE: Clean the cable threads, and do not apply oil to
them.
256RW015
3. Check the shift lock operation:
a. Selector lever should not move out of “P” position
with ignition key in “Lock” position.
b. Selector lever can be moved out of “P” position with
ignition key in “ON” position only when brake pedal
is depressed.
c. Ignition key can be turned to “LOCK” position only
when selector lever is in “P” position (key can be
pulled out).
If (a) and (c) fail, readjust cable. If (b) fails, readjust
connector wiring and brake pedal switch.
Mode Switch
Removal
1. Place selector lever in neutral.
2. Disconnect battery ground cable.
3. Remove mode switch cover (1).
4. Disconnect selector lever (2) from the mode switch.
5. Disconnect transmission harness from the mode
switch connector (3).
6. Remove bracket with mode switch connector from
the transmission case.
7. Remove mode switch connector (3) from the bracket
(4).
8. Remove two mode switch bolts and nut then remove
mode switch (5).
210RW008
Installation
To install, follow the removal steps in the reverse order,
noting the following points;
1. Torque
Mode switch bolt: 13 N
m(1.3kgꞏm/113lbin)
Selector lever nut: 23 N
m (2.3 kgꞏm/17 lb ft)
2. Mode switch setting procedure
Perform either of the following adjustment
procedures:
Procedure 1
a. Place selector lever in neutral.
b. Remove selector lever from the mode switch.
c. Remove the mode switch cover.
d. Loosen the two 10 mm screws.
e. Rotate the mode switch until the slot in the mode
switch housing aligns with the selector shaft
bushing, and insert a 3/32 in. (2.4 mm) drill bit or
punch (1) into the slot.
f. Tighten the screws to 13 Nꞏm (1.3 kgꞏm/113 lb in).
g. After completing adjustment, snap the mode
switch cover into place.