
(6) Install all check balls (1, 3, 4) (Fig. 138) and
the central strainer (2).
(7) Install the strainer (1) (Fig. 139) in the inlet to
torque converter lock-up control solenoid valve.
(8) Position the sealing plate (3) onto the valve
body (4) (Fig. 140).
(9) Install the valve housing (2) onto the valve
body (4) and sealing plate (3).
(10) Install the shift plate Torxtbolts (1) (Fig.
140). Tighten the bolts to 8 N´m (71 in.lbs.).
(11) Install leaf spring (5) (Fig. 140).(12) Install the strainers (1, 2) for the modulating
pressure and shift pressure control solenoid valves
(Fig. 141) into the valve housing.
Fig. 139 Converter Lock-up Solenoid Valve Strainer
Location
1 - CONVERTER LOCK-UP SOLENOID STRAINER
Fig. 140 Shift Plate Components
1-BOLTS-29
2 - VALVE HOUSING
3 - SEALING PLATE
4 - VALVE BODY
5 - LEAF SPRING
Fig. 141 Solenoid Valve Strainer Locations
1 - SOLENOID VALVE STRAINERS
21 - 128 AUTOMATIC TRANSMISSION NAG1 - SERVICE INFORMATIONVA

(13) Install the electrohydraulic control module
(12) onto the shift plate (13) (Fig. 142).
(14) Bend the retaining lug on stiffening rib on
transmission oil temperature sensor to retain the
electrohydraulic control module.
(15) Install the solenoid valves (6 - 11) into shift
plate (13).
NOTE: Check O-rings on solenoid valves for dam-
age and replace if necessary.
(16) Install the leaf springs (5).
(17) Install the Torxtsocket bolts (3, 4) (Fig. 142).
Tighten the bolts to 8 N´m (71 in.lbs.).
NOTE: Pay attention to the different lengths of the
TorxTsocket bolts.
(18) Install the solenoid caps (1, 2).
(19) Install the electrohydraulic unit into the vehi-
cle.
INSTALLATION
(1) Position the electrohydraulic unit in the trans-
mission housing.
(2) Insert selector valve (1) (Fig. 143) in driver of
detent plate (2). When installing the electrohydraulic
control module in the transmission housing, the plas-
tic part of the selector valve (1) must engage in the
driver of the detent plate (2).Fig. 142 Electrical Unit Components
1 - SOLENOID CAP
2 - SOLENOID CAP
3 - BOLT - M6X32
4 - BOLT - M6X30
5 - LEAF SPRING
6 - MODULATING PRESSURE REGULATING SOLENOID VALVE
7 - SHIFT PRESSURE REGULATING SOLENOID
8 - 3-4 SHIFT SOLENOID
9 - TORQUE CONVERTER LOCK-UP SOLENOID
10 - 1-2/4-5 SHIFT SOLENOID
11 - 2-3 SHIFT SOLENOID
12 - ELECTRICHYDRAULIC CONTROL MODULE
13 - SHIFT PLATE
Fig. 143 Connect The Selector Valve To The Detent
Plate
1 - SELECTOR VALVE
2 - DETENT PLATE
VAAUTOMATIC TRANSMISSION NAG1 - SERVICE INFORMATION 21 - 129

(3) Install the Torxtsocket bolts (3) (Fig. 144) and
torque to 8 N´m (71 in.lbs.).
(4) Install a new oil filter (4) (Fig. 144).
(5) Install oil pan (5) (Fig. 144) and torque the oil
pan bolts to 8 N´m (71 in.lbs.).
(6) Install the oil drain plug (8) (Fig. 144) with a
new drain plug gasket (9). Torque the drain plug to
20 N´m (177 in.lbs.).
(7) Install the guide bushing (2) (Fig. 144) into the
transmission housing and install the bolt (11) to hold
the guide bushing in place.(8) Check O-ring on plug connector (1) (Fig. 145),
and replace if necessary.
(9) Install the plug connector (1) into the guide
bushing (2). Turn bayonet lock of guide bushing (2)
clockwise to connect plug connector (1).
(10) Position the heat shield (2) (Fig. 146) onto the
transmission housing and install the screw (1) and
bolt (3) to hold the shield in place.
(11) Fill the transmission with the correct oil
(Refer to LUBRICATION & MAINTENANCE/FLUID
TYPES - DESCRIPTION) using the standard proce-
dure (Refer to 21 - TRANSMISSION/AUTOMATIC -
NAG1/FLUID AND FILTER - STANDARD PROCE-
DURE - TRANSMISSION FILL).
Fig. 144 Install Electrohydraulic Unit
1 - HEAT SHIELD
2 - ELECTROHYDRAULIC UNIT
3 - BOLT
4 - OIL FILTER
5 - OIL PAN
6 - CLAMPING ELEMENT
7 - BOLT
8 - DRAIN PLUG
9 - DRAIN PLUG GASKET
10 - 13-PIN PLUG CONNECTOR
11 - BOLT
12 - GUIDE BUSHING
Fig. 145 Install Wiring Connector Plug
1 - PLUG CONNECTOR
2 - GUIDE BUSHING
Fig. 146 Install Heat Shield
1 - SCREW
2 - HEAT SHIELD
3 - BOLT
21 - 130 AUTOMATIC TRANSMISSION NAG1 - SERVICE INFORMATIONVA

CAUSES OF BURNT FLUID
Burnt, discolored fluid is a result of overheating
which has three primary causes.
1. Internal clutch slippage, usually caused by low
line pressure, inadequate clutch apply pressure, or
clutch seal failure.
2. A result of restricted fluid flow through the
main and/or auxiliary cooler. This condition is usu-
ally the result of a faulty or improperly installed
drainback valve, a damaged oil cooler, or severe
restrictions in the coolers and lines caused by debris
or kinked lines.
3. Heavy duty operation with a vehicle not prop-
erly equipped for this type of operation. Trailer tow-
ing or similar high load operation will overheat the
transmission fluid if the vehicle is improperly
equipped. Such vehicles should have an auxiliary
transmission fluid cooler, a heavy duty cooling sys-
tem, and the engine/axle ratio combination needed to
handle heavy loads.
FLUID CONTAMINATION
Transmission fluid contamination is generally a
result of:
²adding incorrect fluid
²failure to clean dipstick and fill tube when
checking level
²engine coolant entering the fluid
²internal failure that generates debris
²overheat that generates sludge (fluid break-
down)
²failure to replace contaminated converter after
repair
The use of non-recommended fluids can result in
transmission failure. The usual results are erratic
shifts, slippage, abnormal wear and eventual failure
due to fluid breakdown and sludge formation. Avoid
this condition by using recommended fluids only.
The dipstick cap and fill tube should be wiped
clean before checking fluid level. Dirt, grease and
other foreign material on the cap and tube could fall
into the tube if not removed beforehand. Take the
time to wipe the cap and tube clean before withdraw-
ing the dipstick.
Engine coolant in the transmission fluid is gener-
ally caused by a cooler malfunction. The only remedy
is to replace the radiator as the cooler in the radiator
is not a serviceable part. If coolant has circulated
through the transmission, an overhaul is necessary.
The torque converter should be replaced whenever
a failure generates sludge and debris. This is neces-
sary because normal converter flushing procedures
will not remove all contaminants.
STANDARD PROCEDURE
CHECK OIL LEVEL
(1) Verify that the vehicle is parked on a level sur-
face.
(2) Remove locking pin (1) (Fig. 149). Remove the
plate of the locking pin with a suitable tool and press
out the pin remaining in the cap downwards.
(3) Remove cap (2).
WARNING: Risk of accident from vehicle starting off
by itself when engine running. Risk of injury from
contusions and burns if you insert your hands into
the engine when it is started or when it is running.
Secure vehicle to prevent it from moving off by
itself. Wear properly fastened and close-fitting work
clothes. Do not touch hot or rotating parts.
(4) Actuate the service brake. Start engine and let
it run at idle speed in selector lever position ªPº.
(5) Shift through the transmission modes several
times with the vehicle stationary and the engine
idling
(6) Warm up the transmission, wait at least 2 min-
utes and check the oil level with the engine running.
Push the Oil Dipstick 8863A in up to the stop on the
electrohydraulic unit and pull out again, read off oil
level, repeat if necessary.
NOTE: The dipstick will protrude from the fill tube
approximately 75mm (3 inches) when installed.
Fig. 149 Remove Dipstick Tube Cap Lock
1 - LOCKING PIN
2 - TUBE CAP
3 - DIPSTICK TUBE
21 - 132 AUTOMATIC TRANSMISSION NAG1 - SERVICE INFORMATIONVA

To avoid overfilling transmission after a fluid
change or overhaul, perform the following procedure:
(1) Verify that the vehicle is parked on a level sur-
face.
(2) Remove locking pin (1) (Fig. 152). Remove the
plate of the locking pin with a suitable tool and press
out the pin remaining in the cap downwards.
(3) Remove cap (2).
(4) Add following initial quantity of required fluid
(Refer to LUBRICATION & MAINTENANCE/FLUID
TYPES - DESCRIPTION) to transmission:
(a) If only fluid and filter were changed, add7.4
L (14.8 pts.)of transmission fluid to transmission.
(b) If transmission was completely overhauled,
torque converter was replaced or drained, and
cooler was flushed, add7.7 L (16.3 pts.)of trans-
mission fluid to transmission.
(5) Check the transmission fluid (Refer to 21 -
TRANSMISSION/AUTOMATIC - NAG1/FLUID AND
FLUID - STANDARD PROCEDURE - CHECK OIL
LEVEL) and adjust as required.
FLUID / FILTER SERVICE
(1) Run the engine until the transmission oil
reaches operating temperature.
(2) Raise and support vehicle.
(3) Remove the torque converter drain plug access
plug from the bottom of the torque converter hous-
ing.
(4) Rotate the engine clockwise until the torque
converter drain plug (8) (Fig. 153) is aligned with the
access hole.
NOTE: Clean the area around the drain plug to pre-
vent dirt from entering the torque converter.
(5) Using a suitable drain pan to catch the fluid,
remove the torque converter drain plug (8) and allow
the torque converter to drain completely.
(6) Inspect the torque converter drain plug seal (9)
(Fig. 153). Replace the seal if necessary.
(7) Install the torque converter drain plug (8).
Tighten the drain plug to 14 N´m (10 ft.lbs.).
(8) Install the torque converter drain plug access
plug into the bottom of the torque converter housing.
(9) Using a suitable drain pan to catch the fluid,
remove the transmission oil pan drain plug (6) (Fig.
153) and allow the oil pan to drain completely.
(10) Inspect the transmission oil pan drain plug
seal (7). Replace the seal if necessary.
(11) Install the transmission oil pan drain plug (6).
Tighten the drain plug to 20 N´m (15 ft.lbs.).
(12) Remove the bolts (5) and retainers (4) (Fig.
153) holding the oil pan to the transmission.
(13) Remove the transmission oil pan (3) and gas-
ket (2) from the transmission.
Fig. 152 Remove Dipstick Tube Cap Lock
1 - LOCKING PIN
2 - TUBE CAP
3 - DIPSTICK TUBE
Fig. 153 Fluid/Filter Service Points
1 - OIL FILTER
2 - OIL PAN GASKET
3 - OIL PAN
4 - RETAINER
5 - BOLT
6 - OIL PAN DRAIN PLUG
7 - SEAL
8 - TORQUE CONVERTER DRAIN PLUG
9 - SEAL
21 - 134 AUTOMATIC TRANSMISSION NAG1 - SERVICE INFORMATIONVA

(14) Remove the transmission oil filter (1) and
o-ring from the electrohydraulic control unit.
(15) Clean the inside of the oil pan (3) of any
debris. Inspect the oil pan gasket (2) and replace if
necessary.
(16) Install a new oil filter (1) and o-ring into the
electrohydraulic control unit.
(17) Install the oil pan (3) and gasket (2) onto the
transmission.
(18) Install the oil pan bolts (5) and retainers (4).
Torque the bolts to 8 N´m (70 in.lbs.).
(19) Lower the vehicle and add 7.0 L (7.4 qts.) of
transmission fluid to the transmission.
(20) Check the oil level (Refer to 21 - TRANSMIS-
SION/AUTOMATIC - NAG1/FLUID AND FILTER -
STANDARD PROCEDURE - CHECK OIL LEVEL).
FREEWHEELING CLUTCH
DESCRIPTION
Freewheeling clutches (Fig. 154) are installed in
the front planetary gear set between the sun gear
and the stator shaft, and in the rear planetary gear
set between the sun gear and the intermediate shaft.
The freewheel consists of an outer race (4), an
inner race (7), a number of locking elements (3) and
a cage (6) for these locking elements.
OPERATION
The freewheeling clutch (Fig. 155) optimizes indi-
vidual gearshifts. They lock individual elements of a
planetary gear set together or against the transmis-
sion housing in one direction of rotation to allow the
torque to be transmitted.
If the inner race (7) of the freewheeling clutch is
locked and the outer race (4) turns counter-clockwise
(1), the locking elements (3) adopt a diagonal position
on account of their special contours, allowing the
freewheel function. The inner race (4) slides under
the locking elements (3) with minimal friction. If the
rotation of the outer race (4) changes to clockwise (2),
the locking elements (3) stand up and lock the outer
and inner races (4, 7) together.
Fig. 154 Freewheeling Clutch
1 - ROTATION DIRECTION ªA9
2 - ROTATION DIRECTION ªB9
3 - LOCKING ELEMENTS
4 - OUTER RACE
5 - FRONT OR REAR SUN GEAR
6 - LOCKING ELEMENT CAGE
7 - INNER RACE
Fig. 155 Freewheeling Clutch
1 - ROTATION DIRECTION ªA9
2 - ROTATION DIRECTION ªB9
3 - LOCKING ELEMENTS
4 - OUTER RACE
5 - FRONT OR REAR SUN GEAR
6 - LOCKING ELEMENT CAGE
7 - INNER RACE
VAAUTOMATIC TRANSMISSION NAG1 - SERVICE INFORMATION 21 - 135

OPERATION
The holding clutches (Fig. 166) connect the annu-
lus gear, sun gear, or planetary carrier of a planetary
gear set against the transmission housing in order to
transmit the drive torque.
If the piston (16) on multiple-disc holding clutch
B1 (1) is subjected to oil pressure, it presses the
internal (3) and external discs (2) of the disc set
together. The internally toothed disc carrier (15)
locks the sun gear (14) against the housing. The
planetary pinion gears (13) turn on the sun gear (14).
If the multiple-disc holding clutch B2 (5) is actu-
ated via the piston (7), the piston compresses the disc
set. The internally toothed disc carrier (8) locks the
sun gear (12) against the housing. The planetary pin-
ion gears (11) turn on the sun gear (12).
If the multiple-disc holding clutch B3 (4) is actu-
ated via the piston (6), the planetary carrier (9) and
the annulus gear (10) are locked. When the multiple-disc brake B3 (4) is actuated, the direction of rotation
is reversed.
Fig. 166 Holding Clutches
1 - B1 CLUTCH 10 - CENTER PLANETARY GEARSET ANNULUS GEAR
2 - EXTERNALLY TOOTHED DISC 11 - CENTER PLANETARY GEARSET PINION GEARS
3 - INTERNALLY TOOTHED DISC 12 - CENTER PLANETARY GEARSET SUN GEAR
4 - B3 CLUTCH 13 - FRONT PLANETARY GEARSET PINION GEARS
5 - B2 CLUTCH 14 - FRONT PLANETARY GEARSET SUN GEAR
6 - B3 CLUTCH PISTON 15 - B1 CLUTCH INTERNALLY TOOTHED DISC CARRIER
7 - B2 CLUTCH PISTON 16 - B1 CLUTCH PISTON
8 - B2 CLUTCH INTERNALLY TOOTHED DISC CARRIER 17 - B1 CLUTCH EXTERNALLY TOOTHED DISC CARRIER
9 - REAR PLANETARY GEARSET PLANETARY CARRIER
21 - 142 AUTOMATIC TRANSMISSION NAG1 - SERVICE INFORMATIONVA

OPERATION
Signals from the input speed sensors (6, 8) (Fig.
183) are recorded in the transmission control module
(TCM) together with the wheel and engine speeds
and other information and are processed into an
input signal for electronic control.
Input speed sensor N2 (6) records the speed of the
front sun gear via the externally toothed disc carrier
of the multiple-disc clutch K1 (10) and input speed
sensor N3 (8) records the speed of the front planet
carrier via the internally toothed disc carrier of mul-
tiple-disc clutch K1 (3).
OIL PUMP
DESCRIPTION
The oil pump (2) (Fig. 184) (crescent-type pump) is
installed in the bellhousing behind the torque con-
verter and is driven by the drive flange of the torque
converter. The pump creates the oil pressure required
for the hydraulic procedures.
OPERATION
When the engine is running, the oil (Fig. 185) is
pumped through the inlet chamber (5) along the
Fig. 183 Input Speed Sensors
1 - DRIVING CLUTCH K1
2 - TRANSMISSION HOUSING
3 - DRIVING CLUTCH K1 INTERNALLY TOOTHED DISC
4 - EXCITER RING
5 - VALVE HOUSING OF SHIFT PLATE
6 - N2 INPUT SPEED SENSOR
7 - SPRING
8 - N3 INPUT SPEED SENSOR
9 - EXCITER RING
10 - DRIVING CLUTCH K1 EXTERNALLY TOOTHED DISC
Fig. 184 Oil Pump
1 - CRESCENT
2 - OIL PUMP
3 - EXTERNAL GEAR
4 - INTERNAL GEAR
5 - INLET CHAMBER
6 - PRESSURE CHAMBER
Fig. 185 Oil Pump
1 - CRESCENT
2 - OIL PUMP
3 - EXTERNAL GEAR
4 - INTERNAL GEAR
5 - INLET CHAMBER
6 - PRESSURE CHAMBER
21 - 154 AUTOMATIC TRANSMISSION NAG1 - SERVICE INFORMATIONVA