2006 MERCEDES-BENZ SPRINTER automatic transmission fluid

STEERING
TABLE OF CONTENTS
page page
STEERING
DESCRIPTION..........................1
OPERATION............................1
DIAGNOSIS AND TESTING - POWER
STEERING SYSTEM....................1COLUMN................................4
GEAR..................................7
LINKAGE................................9
PUMP..................................11
STEERING
DESCRIPTION
CAUTION: Use approved fluid only in the power
steering system (Refer to LUBRICATION & MAINTE-
NANCE/FLUID TYPES - DESCRIPTION). No other
power steering or automatic transmission fluid is to
be used in the system. Damage may result to the
power steering pump and system if any other fluid
is used, and do not overfill.
Power steering systems consist of:
²Steering column
²Rack and pinion steering gear
²Belt driven hydraulic steering pump
²Pump pressure and return hoses
²Oil Cooler
OPERATION
The steering column shaft is attached to the gear
pinion. The rotation of the pinion moves the gear
rack from side-to-side. This lateral action of the rack
pushes and pulls the tie rods to change the direction
of the front wheels (Fig. 1).
Power assist is provided by an engine mounted
hydraulic pump which supplies hydraulic fluid pres-
sure to the steering gear.
DIAGNOSIS AND TESTING - POWER STEERING
SYSTEM
There is some noise in all power steering systems.
One of the most common is a hissing sound evident at
a standstill parking. Or when the steering wheel is at
the end of it's travel. Hiss is a high frequency noise
similar to that of a water tap being closed slowly. The
noise is present in all valves that have a high velocity
fluid passing through an orifice. There is no relation-
ship between this noise and steering performance.
Fig. 1 STEERING COMPONENTS
1 - POWER STEERING PUMP ASSEMBLY
2 - RESERVOIR
3 - HOSES
4 - TIE ROD ENDS
5 - MOUNTING BOLTS
6 - RACK & PINION
VASTEERING 19 - 1

PUMP
TABLE OF CONTENTS
page page
PUMP
DESCRIPTION.........................11
OPERATION...........................11
DIAGNOSIS AND TESTING - PUMP LEAKAGE . 11
STANDARD PROCEDURE
STANDARD PROCEDURE - POWER
STEERING PUMP - INITIAL OPERATION....11
STANDARD PROCEDURE - FLUSHING
POWER STEERING SYSTEM............12
REMOVAL.............................12
INSTALLATION.........................12
SPECIFICATIONS - TORQUE CHART........13
FLUID
STANDARD PROCEDURE
POWER STEERING PUMP FILL AND BLEED
PROCEDURE........................13FLUID COOLER TUBE
REMOVAL.............................13
INSTALLATION.........................13
HOSES
REMOVAL
REMOVAL - PRESSURE HOSE...........14
REMOVAL - RETURN LINE FROM PUMP TO
COOLER TUBE.......................14
REMOVAL - RETURN HOSE FROM GEAR
TO COOLER TUBE....................14
INSTALLATION
INSTALLATION - PRESSURE HOSE.......14
INSTALLATION - RETURN LINE FROM
PUMP TO COOLER TUBE...............14
INSTALLATION - RETURN HOSE FROM
GEAR TO COOLER TUBE...............14
PUMP
DESCRIPTION
CAUTION: Use approved fluid only in the power
steering system (Refer to LUBRICATION & MAINTE-
NANCE/FLUID TYPES - DESCRIPTION). No other
power steering or automatic transmission fluid is to
be used in the system. Damage may result to the
power steering pump and system if any other fluid
is used, and do not overfill.
The pump is connected to the steering gear via the
pressure hose and the return hose. The pump shaft
has a pressed-on pulley that is belt driven by the
crankshaft pulley.
All vehicles are equipped with a power steering
fluid cooler.
NOTE: Power steering pumps are not interchange-
able with pumps installed on other vehicles.
OPERATION
Hydraulic pressure is provided for the power steer-
ing gear by the belt driven power steering pump. The
power steering pumps are constant flow rate and dis-
placement, vane-type pumps.
DIAGNOSIS AND TESTING - PUMP LEAKAGE
The pump is serviced as an assembly and should
not be disassembled. The plastic pump reservoir and
the reservoir o-rings can be replaced.Check for leaks in the following areas:
²Pump shaft seal behind the pulley
²Pump to reservoir O-ring
²Reservoir cap
²Pressure and return lines
²Flow control valve fitting
STANDARD PROCEDURE
STANDARD PROCEDURE - POWER STEERING
PUMP - INITIAL OPERATION
WARNING: THE FLUID LEVEL SHOULD BE
CHECKED WITH ENGINE OFF TO PREVENT INJURY
FROM MOVING COMPONENTS.
CAUTION: Use approved fluid only in the power
steering system (Refer to LUBRICATION & MAINTE-
NANCE/FLUID TYPES - DESCRIPTION). No other
power steering or automatic transmission fluid is to
be used in the system. Damage may result to the
power steering pump and system if any other fluid
is used, and do not overfill.
Wipe filler cap clean, then check the fluid level.
The dipstick should indicateCOLDwhen the fluid is
at normal temperature.
(1) Turn steering wheel all the way to the left
(2) Fill the pump fluid reservoir to the proper level
and let the fluid settle for at least two (2) minutes.
(3) Raise the front wheels off the ground.
VAPUMP 19 - 11

TRANSMISSION
TABLE OF CONTENTS
page
AUTOMATIC TRANSMISSION NAG1 - SERVICE
INFORMATION............................1
AUTOMATIC TRANSMISSION NAG1 - SERVICE
INFORMATION
TABLE OF CONTENTS
page page
AUTOMATIC TRANSMISSION NAG1 - SERVICE
INFORMATION
DESCRIPTION..........................3
OPERATION............................4
DIAGNOSIS AND TESTING
AUTOMATIC TRANSMISSION............39
PRELIMINARY........................39
ROAD TESTING......................39
AUTOMATIC TRANSMISSION............40
STANDARD PROCEDURE - ALUMINUM
THREAD REPAIR......................42
REMOVAL.............................42
DISASSEMBLY.........................46
ASSEMBLY............................52
INSTALLATION.........................60
SCHEMATICS AND DIAGRAMS............65
SPECIFICATIONS - NAG1 AUTOMATIC
TRANSMISSION......................86
SPECIAL TOOLS - AUTOMATIC
TRANSMISSION - NAG1................87
INPUT CLUTCHES
DESCRIPTION.........................90
OPERATION...........................91
INPUT CLUTCH K1
DISASSEMBLY.........................92
ASSEMBLY............................94
INPUT CLUTCH K2
DISASSEMBLY.........................97
ASSEMBLY............................99
INPUT CLUTCH K3
DISASSEMBLY........................102
ASSEMBLY...........................103
ELECTROHYDRAULIC UNIT
DESCRIPTION........................105
OPERATION..........................112
REMOVAL............................120
DISASSEMBLY........................121
ASSEMBLY...........................125INSTALLATION........................129
FLUID AND FILTER
DESCRIPTION........................131
OPERATION..........................131
DIAGNOSIS AND TESTING
EFFECTS OF INCORRECT FLUID LEVEL . . 131
CAUSES OF BURNT FLUID.............132
FLUID CONTAMINATION...............132
STANDARD PROCEDURE
CHECK OIL LEVEL...................132
TRANSMISSION FILL.................133
FLUID/FILTER SERVICE...............134
FREEWHEELING CLUTCH
DESCRIPTION........................135
OPERATION..........................135
DISASSEMBLY........................136
ASSEMBLY...........................138
GEARSHIFT CABLE
DIAGNOSIS AND TESTING
GEARSHIFT CABLE..................138
REMOVAL............................139
INSTALLATION........................140
HOLDING CLUTCHES
DESCRIPTION........................141
OPERATION..........................142
HOLDING CLUTCH B1
DISASSEMBLY........................143
ASSEMBLY...........................145
HOLDING CLUTCH B2
DISASSEMBLY........................148
ASSEMBLY...........................150
INPUT SPEED SENSORS
DESCRIPTION........................153
OPERATION..........................154
OIL PUMP
DESCRIPTION........................154
OPERATION..........................154
DISASSEMBLY........................155
VATRANSMISSION 21 - 1

DIAGNOSIS AND TESTING
AUTOMATIC TRANSMISSION
CAUTION: Before attempting any repair on a NAG1
automatic transmission, check for Diagnostic Trou-
ble Codes with the appropriate scan tool.
Transmission malfunctions may be caused by these
general conditions:
²Poor engine performance.
²Improper adjustments.
²Hydraulic malfunctions.
²Mechanical malfunctions.
²Electronic malfunctions.
²Transfer case performance (if equipped).
Diagnosis of these problems should always begin
by checking the easily accessible variables: fluid level
and condition, gearshift cable adjustment. Then per-
form a road test to determine if the problem has been
corrected or if more diagnosis is necessary.
PRELIMINARY
Two basic procedures are required. One procedure
for vehicles that are drivable and an alternate proce-
dure for disabled vehicles (will not back up or move
forward).
VEHICLE IS DRIVABLE
(1) Check for transmission fault codes using the
appropriate scan tool.
(2) Check fluid level and condition.
(3) Adjust gearshift cable if complaint was based
on delayed, erratic, or harsh shifts.
(4) Road test and note how transmission upshifts,
downshifts, and engages.
VEHICLE IS DISABLED
(1) Check fluid level and condition.(2) Check for broken or disconnected gearshift
cable.
(3) Check for cracked, leaking cooler lines, or loose
or missing pressure-port plugs.
(4) Raise and support vehicle on safety stands,
start engine, shift transmission into gear, and note
following:
(a) If propeller shaft turns but wheels do not,
problem is with differential or axle shafts.
(b) If propeller shaft does not turn and transmis-
sion is noisy, stop engine. Remove oil pan, and
check for debris. If pan is clear, remove transmis-
sion and check for damaged driveplate, converter,
oil pump, or input shaft.
(c) If propeller shaft does not turn and transmis-
sion is not noisy, perform hydraulic-pressure test to
determine if problem is hydraulic or mechanical.
ROAD TESTING
Before road testing, be sure the fluid level and con-
trol cable adjustments have been checked and
adjusted if necessary. Verify that all diagnostic trou-
ble codes have been resolved.
Observe engine performance during the road test.
A poorly tuned engine will not allow accurate analy-
sis of transmission operation.
Operate the transmission in all gear ranges. Check
for shift variations and engine flare which indicates
slippage. Note if shifts are harsh, spongy, delayed,
early, or if part throttle downshifts are sensitive.
Slippage indicated by engine flare, usually means
clutch, overrunning clutch, or line pressure problems.
A slipping clutch can often be determined by com-
paring which internal units are applied in the vari-
ous gear ranges. The Clutch Application chart
CLUTCH APPLICATION provides a basis for analyz-
ing road test results.
CLUTCH APPLICATION
GEAR RATIO B1 B2 B3 K1 K2 K3 F1 F2
1 3.59 X* X X* X X
2 2.19 X X X* X
3 1.41 X X X
4 1.00 X X X
5 0.83 X X X X*
N N/A X X
R 3.16 X* X X X
R - Limp In 1.93 X X X
* = The shift components required during coast.
VAAUTOMATIC TRANSMISSION NAG1 - SERVICE INFORMATION 21 - 39

NOTE: During the measurement the snap ring (7)
(Fig. 49) must contact the upper bearing surface of
the groove in the outer multiple-disc carrier (8).
NOTE: Pay attention to sequence of discs. If the
original clutch discs are reused, be sure to return
the disc identified on disassembly as belonging on
top of the spring washer (4) to its original location.
Place new friction multiple-discs in ATF fluid for
one hour before installing.
(4) Insert and measure spring washer (4) (Fig. 49)
and multiple-disc pack B3 (2, 6).
(a) Put multiple-discs for multiple-disc holding
clutch B3 together in the sequence shown in the
illustration and insert individually.
(b)
CAUTION: Apply only light pressure (less than 10 N
(3 lbs.) of force) to the clutch pack when measuring
the clutch clearance with the feeler gauge. Applying
excessive force to the clutch will give an incorrect
reading and lead to a transmission failure.Using a
feeler gauge, determine the play ªLº at three points
between the snap ring (7) and outer multiple-disc
(1). B3 clutch clearance should be 1.0-1.4 mm
(0.039-0.055 in.). Adjust the clearance as necessary.
(c) Adjust with snap-ring (7), if necessary. Snap-
rings are available in thicknesses of 3.2 mm (0.126
in.), 3.5 mm (0.138 in.), 3.8 mm (0.150 in.), 4.1 mm
(0.162 in.), 4.4 mm (0.173 in.), and 4.7 mm (0.185
in.).
(5) Check that the K1 clutch feed hole (1) (Fig. 50)
in the inner hub of clutch B1 is free before installing
clutch B1.
Fig. 50 Check K1 Feed Hole
1 - K1 CLUTCH FEED HOLE
VAAUTOMATIC TRANSMISSION NAG1 - SERVICE INFORMATION 21 - 53

(21) Install the oil drain plug (2) (Fig. 78) with a
new seal into the transmission oil pan. Tighten the
drain plug to 20 N´m (14.5 ft.lbs.).
(22) Lower vehicle and fill transmission with cor-
rect automatic transmission fluid (Refer to 21 -
TRANSMISSION/AUTOMATIC - NAG1/FLUID AND
FILTER - STANDARD PROCEDURE).
(23) Road test the vehicle and verify the repair.
Fig. 77 Fill Tube
1 - FILL TUBE
2 - BOLTS TO CYLINDER HEAD AND TRANSMISSION HOUS-
ING
3 - BOLT TO TRANSMISSION FLANGE
Fig. 78 Oil Drain Plug
1 - SEAL
2 - DRAIN PLUG
21 - 64 AUTOMATIC TRANSMISSION NAG1 - SERVICE INFORMATIONVA

(4) Place Multi-use Spring Compressor 8900 (2)
(Fig. 84) on spring plate and compress the spring
until the groove of the snap-ring (1) is exposed.
(5) Insert snap-ring (1) (Fig. 83). After installing,
check snap-ring for correct seat.
CAUTION: When working with double sided friction
discs, an externally lugged steel plate is installed
first, followed by a friction disc, and continuing on
until all the required discs are installed. When work-
ing with single sided friction discs, an externallylugged disc is installed first, followed by an inter-
nally lugged disc, and continuing on until all the
required discs are installed. All single sided discs
are installed with the friction side up.
NOTE: Pay attention to the sequence of discs. If the
original clutch discs are reused, be sure to return
the disc identified on disassembly as belonging on
top of the spring plate (8) to its original location.
NOTE: Place new friction multiple-discs in ATF fluid
for one hour before installing.
(6) Insert multiple-disc pack (12) in the outer mul-
tiple-disc carrier.
(7) Insert snap-ring (11).
(8) Measure the K1 clutch pack clearance by
mounting Pressing Tool 8901 (1) (Fig. 85) on outer
multiple disc.
(9) Using a lever press, compress pressing tool as
far as the stop (then the marking ring is still visible,
see small arrow).
(10) For transmissions using double sided friction
discs, use a feeler gauge to determine the play ªLº
(Fig. 86) at three points between the snap-ring (5)
and outer multiple-disc (3).
(11) During the measurement the snap-ring (5)
must contact the upper bearing surface of the groove
in the outer multiple-disc carrier (4).
(12) The correct clutch clearance for transmissions
with double sided friction discs is 2.7-3.1 mm (0.106-
0.122 in.) for three friction disc versions, 3.0-3.4 mm
Fig. 84 Compress the Disc Spring
1 - SNAP-RING
2 - MULTI-USE SPRING COMPRESSOR 8900
Fig. 85 Measure K1 Clutch Clearance
1 - PRESSING TOOL 8901
2 - K1 OUTER DISC CARRIER
Fig. 86 Input Clutch K1 Stack-up - Double Sided
Discs
1 - OUTER MULTIPLE DISC - 1.8MM (0.071 IN.)
2 - OUTER MULTIPLE DISC - 2.8MM (0.110 IN.)
3 - OUTER MULTIPLE DISC - 4.0MM (0.158 IN.)
4 - K1 OUTER DISC CARRIER
5 - SNAP-RING
6 - FRICTION DISCS
7 - DISC SPRING
8 - PISTON
VAAUTOMATIC TRANSMISSION NAG1 - SERVICE INFORMATION 21 - 95

ASSEMBLY
(1) Install piston (6) (Fig. 95) in the outer multi-
ple-disc carrier (8). Check sealing ring (7), replace if
necessary. The rounded off edges of the sealing ring
must point outwards.
(2) Insert disc spring (5). Insert disc spring with
the curvature towards the piston.
(3) Mount the Multi-use Spring Compressor 8900
(9) on the spring plate and clamp until the snap-ring
groove is exposed.
(4) Insert snap-ring (4). The collar of the snap-ring
must point towards the multiple-disc pack.
CAUTION: When working with double sided friction
discs, an externally lugged steel plate is installed
first, followed by a friction disc, and continuing on
until all the required discs are installed. When work-
ing with single sided friction discs, an externally
lugged disc is installed first, followed by an inter-
nally lugged disc, and continuing on until all the
required discs are installed. All single sided discs
are installed with the friction side up.
NOTE: Pay attention to the sequence of discs. If the
original clutch discs are reused, be sure to returnthe disc identified on disassembly as belonging on
top of the spring plate (3) to its original location.
NOTE: Place new friction multiple-discs in ATF fluid
for one hour before installing.
(5) Install disk spring (3) and multiple-disc pack
(2) in outer multiple-disc carrier (8).
(6) Insert snap-ring (1).
Fig. 95 Input Clutch K3 Components
1 - SNAP-RING 6 - PISTON
2 - MULTIPLE DISC PACK 7 - SEALING RING
3 - DISC SPRING 8 - OUTER DISC CARRIER
4 - SNAP-RING 9 - MULTI-USE SPRING COMPRESSOR 8900
5 - SPRING PLATE
VAAUTOMATIC TRANSMISSION NAG1 - SERVICE INFORMATION 21 - 103