2005 MERCEDES-BENZ SPRINTER Service Repair Manual

OUTPUT SHAFT SEAL
REMOVAL
(1) Remove the propeller shaft (Refer to 3 - DIF-
FERENTIAL & DRIVELINE/PROPELLER SHAFT/
PROPELLER SHAFT - REMOVAL). Move propeller
shaft to the right and tie up.
(2) Verify that the transmission is in PARK in
order to prepare for the removal of the output shaft
nut.
(3) Remove the nut holding the propeller shaft
flange to the output shaft and remove the flange.
(4) Remove the output shaft seal with suitable
screw and slide hammer.
INSTALLATION
(1) Position the new output shaft seal over the out-
put shaft and against the transmission case.
(2) Use Seal Installer 8902A to install the seal
(Fig. 182).
(3) Verify that the transmission is in PARK in
order to prepare for the installation of the output
shaft nut.
(4) Install the propeller shaft flange onto the out-
put shaft and install an new flange nut. Tighten the
flange nut to 120 N´m (88.5 ft.lbs.).
(5) Stake the output shaft nut to the output shaft
as follows.
(a) Place the Staking Tool 9078 and Driver Han-
dle C-4171 onto the output shaft.
(b) Rotate the Staking Tool 9078 until the align-
ment pin engages the output shaft notch (Fig. 183).
(c) Press downward on the staking tool until the
staking pin contacts the output shaft nut flange
(Fig. 184).(d) Strike the Driver handle C-4171 with a suit-
able hammer until the output shaft nut is securely
staked to the output shaft.
(6) Install the propeller shaft (Refer to 3 - DIF-
FERENTIAL & DRIVELINE/PROPELLER SHAFT/
PROPELLER SHAFT - INSTALLATION).
PARK LOCK CABLE
REMOVAL
(1) Disconnect battery.
(2) Move selector lever to position9D9.
Fig. 182 Install the Output Shaft Seal
1 - SEAL INSTALLER 8902A
2 - TRANSMISSION CASE
Fig. 183 Align Staking Tool 9078
1 - PROPELLER SHAFT FLANGE
2 - STAKING TOOL 9078
3 - ALIGNMENT PIN
4 - OUTPUT SHAFT NOTCH
Fig. 184 Stake Output Shaft Nut
1 - STAKING TOOL 9078
2 - PROPELLER FLANGE
3 - STAKING PIN
VAAUTOMATIC TRANSMISSION - NAG1 21 - 125

(3) Remove top section (3) (Fig. 185) of the center
section of instrument panel.
(4) Remove bottom section (2) (Fig. 186) of the cen-
ter section of instrument panel.
(5) Disconnect the park lock cable coupling (1)
(Fig. 187) from the shift lever assembly (SLA). Press
locking tab (2) together and push coupling (1) against
the spring force into the SLA, twist through 90É
(right or left) and pull off.
(6) Remove the lower steering column shroud.
(7) Loosen the park lock cable (2) (Fig. 188) from
the ignition switch.
(8) Remove the park lock cable (2) (Fig. 189) from
the ignition switch.
(9) Remove the park lock cable from the vehicle.
INSTALLATION
(1) Route the park lock cable through the instru-
ment panel between the steering column and the
shift lever assembly (SLA).
(2) Install the park lock cable (2) (Fig. 190) to the
ignition switch.
(3) Tighten the park lock cable (2) (Fig. 191) to the
ignition switch.
(4) Install the lower steering column shroud.
Fig. 185 Remove Top Section Of Center Instrument
Panel
1 - SHIFT LEVER ASSEMBLY FRAME TRIM
2 - STORAGE COMPARTMENT
3 - TOP CENTER PART OF INSTRUMENT PANEL
4 - SCREW
5 - PLUG CONNECTIONS
6 - ASHTRAY
Fig. 186 Remove Bottom Section Of Center
Instrument Panel
1 - SCREW
2 - BOTTOM CENTER PART OF INSTRUMENT PANEL
Fig. 187 Disengage Park Lock Cable From SLA
1 - PARK LOCK CABLE COUPLING
2 - LOCK TAB
3 - BOLT
4 - SHIFT LEVER ASSEMBLY (SLA)
5 - CONNECTOR
21 - 126 AUTOMATIC TRANSMISSION - NAG1VA
PARK LOCK CABLE (Continued)

(5) Connect the park lock cable coupling (1) (Fig.
192) to the shift lever assembly (SLA). Press locking
tab (2) together and push coupling (1) against the
spring force into the SLA, twist through 90É (right or
left) until locked.(6) Install the bottom section (2) (Fig. 193) of the
center section of instrument panel.
(7) Install the top section (3) (Fig. 194) of the cen-
ter section of instrument panel.
(8) Connect battery.
(9) Verify repair.
Fig. 188 Loosen Park Lock Cable From Ignition
Switch
1 - IGNITION SWITCH
2 - PARK LOCK CABLE
Fig. 189 Remove Park Lock Cable From Ignition
Switch
1 - IGNITION SWITCH
2 - PARK LOCK CABLE
Fig. 190 Install Park Lock Cable to Ignition Switch
1 - IGNITION SWITCH
2 - PARK LOCK CABLE
Fig. 191 Tighten Park Lock Cable to Ignition Switch
1 - IGNITION SWITCH
2 - PARK LOCK CABLE
VAAUTOMATIC TRANSMISSION - NAG1 21 - 127
PARK LOCK CABLE (Continued)

PISTONS
DESCRIPTION
There are several sizes and types of pistons used in
an automatic transmission. Some pistons are used to
apply clutches. They all have in common the fact
that they are round or circular in shape, located
within a smooth walled cylinder, which is closed at
one end and converts fluid pressure into mechanical
movement. The fluid pressure exerted on the piston
is contained within the system through the use of
piston rings or seals.
OPERATION
The principal which makes this operation possible
is known as Pascal's Law. Pascal's Law can be stated
as: ªPressure on a confined fluid is transmitted
equally in all directions and acts with equal force on
equal areas.º
Fig. 192 Engage Park Lock Cable to SLA
1 - PARK LOCK CABLE COUPLING
2 - LOCK TAB
3 - BOLT
4 - SHIFT LEVER ASSEMBLY (SLA)
5 - CONNECTOR
Fig. 193 Install Bottom Section Of Center
Instrument Panel
1 - SCREW
2 - BOTTOM CENTER PART OF INSTRUMENT PANEL
Fig. 194 Install Top Section Of Center Instrument
Panel
1 - SHIFT LEVER ASSEMBLY FRAME TRIM
2 - STORAGE COMPARTMENT
3 - TOP CENTER PART OF INSTRUMENT PANEL
4 - SCREW
5 - PLUG CONNECTIONS
6 - ASHTRAY
21 - 128 AUTOMATIC TRANSMISSION - NAG1VA
PARK LOCK CABLE (Continued)

PRESSURE
Pressure (Fig. 195) is nothing more than force
(lbs.) divided by area (in or ft.), or force per unit
area. Given a 100 lb. block and an area of 100 sq. in.
on the floor, the pressure exerted by the block is: 100
lbs. 100 in or 1 pound per square inch, or PSI as it is
commonly referred to.
PRESSURE ON A CONFINED FLUID
Pressure is exerted on a confined fluid (Fig. 196)
by applying a force to some given area in contact
with the fluid. A good example of this is a cylinder
filled with fluid and equipped with a piston that is
closely fitted to the cylinder wall. If a force is applied
to the piston, pressure will be developed in the fluid.
Of course, no pressure will be created if the fluid is
not confined. It will simply ªleakº past the piston.
There must be a resistance to flow in order to create
pressure. Piston sealing is extremely important in
hydraulic operation. Several kinds of seals are used
to accomplish this within a transmission. These
include but are not limited to O-rings, D-rings, lip
seals, sealing rings, or extremely close tolerances
between the piston and the cylinder wall. The force
exerted is downward (gravity), however, the principle
remains the same no matter which direction is taken.
The pressure created in the fluid is equal to the force
applied, divided by the piston area. If the force is 100
lbs., and the piston area is 10 sq. in., then the pres-
sure created equals 10 PSI. Another interpretation of
Pascal's Law is that regardless of container shape or
size, the pressure will be maintained throughout, as
long as the fluid is confined. In other words, thepressure in the fluid is the same everywhere within
the container.
FORCE MULTIPLICATION
Using the 10 PSI example used in the illustration
(Fig. 197), a force of 1000 lbs. can be moved with a
force of only 100 lbs. The secret of force multiplica-
tion in hydraulic systems is the total fluid contact
area employed. The illustration, (Fig. 197), shows an
area that is ten times larger than the original area.
The pressure created with the smaller 100 lb. input
is 10 PSI. The concept ªpressure is the same every-
whereº means that the pressure underneath the
larger piston is also 10 PSI. Pressure is equal to the
force applied divided by the contact area. Therefore,
by means of simple algebra, the output force may be
found. This concept is extremely important, as it is
also used in the design and operation of all shift
valves and limiting valves in the valve body, as well
as the pistons, of the transmission, which activate
the clutches and bands. It is nothing more than
using a difference of area to create a difference in
pressure to move an object.
PISTON TRAVEL
The relationship between hydraulic lever and a
mechanical lever is the same. With a mechanical
lever it's a weight-to-distance output rather than a
pressure-to-area output. Using the same forces and
areas as in the previous example, the smaller piston
(Fig. 198) has to move ten times the distance
required to move the larger piston one inch. There-
fore, for every inch the larger piston moves, the
smaller piston moves ten inches. This principle is
true in other instances also. A common garage floor
jack is a good example. To raise a car weighing 2000
lbs., an effort of only 100 lbs. may be required. For
every inch the car moves upward, the input piston at
the jack handle must move 20 inches downward.
Fig. 195 Force and Pressure Relationship
Fig. 196 Pressure on a Confined Fluid
VAAUTOMATIC TRANSMISSION - NAG1 21 - 129
PISTONS (Continued)

PLANETARY GEARTRAIN
DESCRIPTION
Three planetary gear sets (Fig. 199) are used to
produce the different gear ratios. These are located
in the mechanical part of the transmission as the
front, middle and rear planetary gear sets.
OPERATION
The annulus gear (1) (Fig. 200) and sun gear (3)
elements of a planetary gear system are alternately
driven and braked by the actuating elements of the
multi-plate clutch and multiple-disc brake. The plan-
etary pinion gears (2) can turn on the internal gear-
ing of the annulus gear (1) and on the external
gearing of the sun gear (3). This allows for a variety
of gear ratios and the reversal of the rotation direc-
tion without the need for moving gear wheels or shift
collars. When two components of the planetary gear
set are locked together, the planetary gear set is
locked and turns as a closed unit.
Fig. 197 Force Multiplication
Fig. 198 Piston Travel
Fig. 199 Planetary Geartrain
1 - ANNULUS GEAR
2 - PLANETARY PINION GEARS
3 - SUN GEAR
4 - PLANETARY CARRIER
Fig. 200 Planetary Geartrain
1 - ANNULUS GEAR
2 - PLANETARY PINION GEARS
3 - SUN GEAR
4 - PLANETARY CARRIER
21 - 130 AUTOMATIC TRANSMISSION - NAG1VA
PISTONS (Continued)

The torque and engine speed are converted accord-
ing to the lever ratios and the ratio of the number of
teeth on the driven gears to that on the drive gears,
and is referred to as the gear ratio. The overall ratio
of a number of planetary gear sets connected in
series is obtained by multiplying the partial ratios.
DISASSEMBLY
(1) Remove upper two visible Teflon rings (1) (Fig.
201) from output shaft.
(2) Remove retaining ring (11), shim (10), thrust
needle bearing (9) and thrust washer (8) from output
shaft.
(3) Remove clutch K3 (7).
(4) Remove rear tubular shaft/freewheeling clutch
F2 (6) (Fig. 201) from output shaft.
(5) Remove rear gear set (5) with integrated tubu-
lar shaft of center gear set from output shaft.
(6) Remove thrust washer (4).
ASSEMBLY
(1) Mount thrust washer (4) (Fig. 202) with the
collar pointing towards the planet carrier.
(2) Mount rear gear set (5) with integrated tubular
shaft of the center gear set on output shaft.
(3) Using grease, install lower three Teflon rings
(1) (Fig. 202) in the groove so that the joint stays
together
(4) Put rear tubular shaft/freewheeling clutch F2
(6) onto output shaft.
(5) Install clutch K3 (7).
(6) Mount retaining ring, shim, thrust needle bear-
ing and thrust washer (8 - 11) (Fig. 202).
(7) Using grease, insert the upper two Teflon rings
(1) in the groove so that the joint remains together.
Fig. 201 Output Shaft with Center and Rear Planetary Geartrain
1 - TEFLON RINGS 7 - DRIVING CLUTCH K3
2 - OUTPUT SHAFT WITH CENTER PLANETARY CARRIER 8 - THRUST WASHER
3 - NEEDLE BEARING 9 - AXIAL NEEDLE BEARING
4 - THRUST WASHER 10 - SHIM
5 - REAR PLANETARY GEAR SET 11 - RETAINING RING
6 - REAR HOLLOW SHAFT/FREEWHEELING CLUTCH F2
VAAUTOMATIC TRANSMISSION - NAG1 21 - 131
PLANETARY GEARTRAIN (Continued)

Fig. 202 Output Shaft with Center and Rear Planetary Geartrain
1 - TEFLON RINGS 7 - DRIVING CLUTCH K3
2 - OUTPUT SHAFT WITH CENTER PLANETARY CARRIER 8 - THRUST WASHER
3 - NEEDLE BEARING 9 - AXIAL NEEDLE BEARING
4 - THRUST WASHER 10 - SHIM
5 - REAR PLANETARY GEAR SET 11 - RETAINING RING
6 - REAR HOLLOW SHAFT/FREEWHEELING CLUTCH F2
21 - 132 AUTOMATIC TRANSMISSION - NAG1VA
PLANETARY GEARTRAIN (Continued)