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) Sprag Free Wheel (One Way Clutch) (PFW)
7A–5 AUTOMATIC TRANSMISSION (4L30–E)
Normal Operation Of 1998 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 140
C
(284
F).
The ATF warning lamp goes off again when the
transmission oil temperature is below 130
C (266F).
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–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
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–15 AUTOMATIC TRANSMISSION (4L30–E)
Chart 4: Poor Shifting In All Gears (All Harsh Or All Soft)
StepActionYe sNo
1Check line pressure. Refer to Line Pressure Test in this section.
Was line pressure normal?
Go to Step 2Go to Step 3
21. Check for these conditions which could affect clutch apply
time:
– Defective band apply solenoid (323).
– Defective servo or/and accumulator piston.
– Excessive clutch piston travel.
2. Check of possible causes of internal leaks:
– Cut or damaged sealing ring(s)
– Damaged sealing gasket(s)
– Check ball missing or out of location in 2nd and 3rd clutch
pistons.
3. Check for caused of burned clutch plates or band.
Was the problem found?
Repair or replace—
3Was the line pressure high?
Go to Step 4
Use Chart 15a:
Possible Causes
of Low Line
Pressure in this
section
4Were DTCs P0560 and P0705 set?
Diagnose those
DTC(s) first
Use Chart 15b:
Possible Causes
of High Line
Pressure in this
section
Chart 5a: Delays In Drive And Reverse
NOTE: A short delay (less than 3 seconds) when first
engaging drive or reverse after allowing vehicle to sit
overnight is normal.
Step
ActionYe sNo
1Check line pressure. Refer to Line Pressure Test in this section.
Was line pressure normal?More than 3
second delay in
drive and reverse
with engine off 1
hour or less.
Teflon seals (508)
on turbine shaft
damaged. Repair
Use Chart 15a:
Possible Causes
of Low Line
Pressure in this
section.
Chart 5b: Delays In Reverse Only
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.
2Main case valve body gasket (88) damaged.
– Reverse check ball (85) in valve body (84) missing or out of
location.
– Check for restrictions at valve body transfer plate orifice.
Was the problem found?
Repair—
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–19 AUTOMATIC TRANSMISSION (4L30–E)
Chart 13: Shudder Only During Torque Converter Clutch (TCC) Applying
StepActionYe sNo
11. TCC shudder is one of the most commonly misdiagnosed
conditions in an automatic transmission. The key to
diagnosing TCC shudder is to note when it happens and under
what conditions. Once the TCC has been fully applied, it is
nearly impossible to make it shudder. TCC shudder (short
burst of noise normally less than 1 second) will only occur
during clutch applying. It is not a steady state condition.
2. Drive until whole drivetrain is at normal operating temperature.
– On 4WD vehicles, the test must be performed with transfer
case selector lever in “2H” position.
– Shudder is a short burst of noise normally less than 1 second
in duration, and can be induced by the following maneuver:
3. From coast condition at 50 mph in “D” range (Normal mode),
depress the throttle to 1/4-1/3 throttle. If present, shudder will
occur within 5 seconds together with TCC application.(The
scan tool may be used to determine the exact time of TCC
applying)
Was the problem found?
Replace
transmission fluid
and filter (remove
both pans) and
flush cooler lines.
Replace
converter
assembly and
O-ring on turbine
shaft
Perform
mechanical
inspection of
other drivetrain
components.
Chart 14: Possible Causes Of Transmission Noise
CAUTION: Before checking transmission for what
is believed to be transmission noise, ensure
presence and positioning of insulating plugs, pads
etc. Also make sure that noise does not come from
other drivetrain components.
Condition
Possible causeCorrection
Whine or BuzzOil level lowFill with ATF, check for external
leaks.
Plugged or restricted oil filterInspect oil filter.
Replace oil filter or ATF as necessary.
Damaged oil filter gasketReplace oil filter gasket.
Knocking noise from front of
transmission
Loose bolts (Converter to flex plate)Tighten to specifications.
transmission.Cracked or broken flex plateReplace flex plate.
Converter damagedReplace converter.
Knocking noise while driving, mostly
on acceleration.Transmission mount loose or brokenTighten mount bolts or replace
transmission mount.
Cooler line mounts loose or brokenTighten or replace cooler line
mounts.
Cooler lines touching body or frameRepair or replace as necessary.
Knocking noise when vehicle is
stationary
Loose flex plate mounting boltsTighten to specifications.
stationary.Cracked or broken flex plateReplace flex plate.
Damaged converterReplace converter.
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)