DODGE RAM 2001 Service Repair Manual

3-4 ACCUMULATOR
(1) Position converter clutch valve and 3-4 shift
valve springs in housing (Fig. 308).
(2) Loosely attach accumulator housing with right-
side screw (Fig. 308). Install only one screw at this
time as accumulator must be free to pivot upward for
ease of installation.
(3) Install 3-4 shift valve and spring.
(4) Install converter clutch timing valve and
spring.
(5) Position plug on end of converter clutch valve
spring. Then compress and hold springs and plug in
place with fingers of one hand.
(6) Swing accumulator housing upward over valve
springs and plug.
(7) Hold accumulator housing firmly in place and
install remaining two attaching screws. Be sure
springs and clutch valve plug are properly seated
(Fig. 309). Tighten screws to 4 N´m (35 in. lbs.).
VALVE BODY FINAL
(1) Install boost valve, valve spring, retainer and
cover plate. Tighten cover plate screws to 4 N´m (35
in. lbs.) torque.
(2) Insert manual lever detent spring in upper
housing.
(3) Position detent ball on end of spring. Then hold
detent ball and spring in detent housing with
Retainer Tool 6583 (Fig. 310).
(4) Install throttle lever in upper housing. Then
install manual lever over throttle lever and start
manual lever into housing.
(5) Align manual lever with detent ball and man-
ual valve. Hold throttle lever upward. Then press
down on manual lever until fully seated. Remove
detent ball retainer tool after lever is seated.(6) Then install manual lever seal, washer and
E-clip.
(7) Verify that throttle lever is aligned with end of
kickdown valve stem and that manual lever arm is
engaged in manual valve (Fig. 311).
(8) Position line pressure adjusting screw in
adjusting screw bracket.
(9) Install spring on end of line pressure regulator
valve.
(10) Install switch valve spring on tang at end of
adjusting screw bracket.
Fig. 307 Securing Boost Valve Tube With Brace
Tabs
1 - BEND TABS UP AGAINST TUBE AS SHOWNFig. 308 Converter Clutch And 3-4 Shift Valve
Springs
1 - RIGHT-SIDE SCREW
2 - 3-4 ACCUMULATOR
3 - 3-4 SHIFT VALVE SPRING
4 - CONVERTER CLUTCH VALVE SPRING
Fig. 309 Seating 3-4 Accumulator On Lower
Housing
1 - ACCUMULATOR BOX
2 - CONVERTER CLUTCH VALVE PLUG
21 - 816 AUTOMATIC TRANSMISSION - 47REBR/BE
VALVE BODY (Continued)

(11) Install manual valve.
(12) Install throttle valve and spring.
(13) Install kickdown valve and detent.
(14) Install pressure regulator valve.
(15) Install switch valve.
(16) Position adjusting screw bracket on valve
body. Align valve springs and press bracket into
place. Install short, upper bracket screws first and
long bottom screw last. Verify that valve springs and
bracket are properly aligned. Then tighten all three
bracket screws to 4 N´m (35 in. lbs.) torque.
(17) Perform Line Pressure and Throttle Pressure
adjustments. (Refer to 21 - TRANSMISSION/TRAN-
SAXLE/AUTOMATIC/VALVE BODY - ADJUST-
MENTS)
(18) Lubricate solenoid case connector O-rings and
shaft of manual lever with light coat of petroleum
jelly.
(19) Attach solenoid case connector to 3-4 accumu-
lator with shoulder-type screw. Connector has small
locating tang that fits in dimple at top of accumula-
tor housing (Fig. 312). Seat tang in dimple before
tightening connector screw.
(20) Install solenoid assembly and gasket. Tighten
solenoid attaching screws to 8 N´m (72 in. lbs.)
torque.
(21) Verify that solenoid wire harness is properly
routed (Fig. 313). Solenoid harness must be clear of
manual lever and park rod and not be pinched
between accumulator housing and cover.
GOVERNOR BODY, SENSOR AND SOLENOID
(1) Turn valve body assembly over so accumulator
side of transfer plate is facing down.
(2) Install new O-rings on governor pressure sole-
noid and sensor.
(3) Lubricate solenoid and sensor O-rings with
clean transmission fluid.(4) Install governor pressure sensor in governor
body.
(5) Install governor pressure solenoid in governor
body. Push solenoid in until it snaps into place in
body.
(6) Position governor body gasket on transfer
plate.
(7) Install retainer plate on governor body and
around solenoid. Be sure solenoid connector is posi-
tioned in retainer cutout.
(8) Align screw holes in governor body and trans-
fer plate. Then install and tighten governor body
screws to 4 N´m (35 in. lbs.) torque.
Fig. 310 Detent Ball Spring
1 - SPECIAL TOOL 6583 POSITIONED ON DETENT HOUSING
Fig. 311 Manual And Throttle Lever Alignment
1 - THROTTLE LEVER
2 - MANUAL LEVER VALVE ARM
3 - MANUAL VALVE
4 - KICKDOWN VALVE
Fig. 312 Solenoid Harness Case Connector
Shoulder Bolt
1 - SOLENOID HARNESS CASE CONNECTOR
2 - 3-4 ACCUMULATOR HOUSING
BR/BEAUTOMATIC TRANSMISSION - 47RE 21 - 817
VALVE BODY (Continued)

(9) Connect harness wires to governor pressure
solenoid and governor pressure sensor.
(10) Install fluid filter and pan.
(11) Lower vehicle.
(12) Fill transmission with recommended fluid and
road test vehicle to verify repair.
INSTALLATION
(1) Check condition of O-ring seals on valve body
harness connector (Fig. 314). Replace seals on con-
nector body if cut or worn.
(2) Check condition of manual lever shaft seal in
transmission case. Replace seal if lip is cut or worn.
Install new seal with 15/16 deep well socket (Fig.
315).
(3) Check condition of seals on accumulator piston
(Fig. 316). Install new piston seals, if necessary.
(4) Place valve body manual lever in low (1 posi-
tion) so ball on park lock rod will be easier to install
in sprag.
(5) Lubricate shaft of manual lever with petroleum
jelly. This will ease inserting shaft through seal in
case.
(6) Lubricate seal rings on valve body harness con-
nector with petroleum jelly.
(7) Position valve body in case and work end of
park lock rod into and through pawl sprag. Turn pro-
peller shaft to align sprag and park lock teeth if nec-
essary. The rod will click as it enters pawl. Move rod
to check engagement.
CAUTION: It is possible for the park rod to displace
into a cavity just above the pawl sprag during
installation. Make sure the rod is actually engaged
in the pawl and has not displaced into this cavity.(8) Install accumulator springs and piston into
case. Then swing valve body over piston and outer
spring to hold it in place.
(9) Align accumulator piston and outer spring,
manual lever shaft and electrical connector in case.
(10) Then seat valve body in case and install one
or two bolts to hold valve body in place.
(11) Tighten valve body bolts alternately and
evenly to 11 N´m (100 in. lbs.) torque.
(12) Install new fluid filter on valve body. Tighten
filter screws to 4 N´m (35 in. lbs.) torque.
(13) Install throttle and gearshift levers on valve
body manual lever shaft.
(14) Check and adjust front and rear bands if nec-
essary.
(15) Connect solenoid case connector wires.
(16) Install oil pan and new gasket. Tighten pan
bolts to 17 N´m (13 ft. lbs.) torque.
(17) Lower vehicle and fill transmission with
MopartATF +4, type 9602, fluid.
(18) Check and adjust gearshift and throttle valve
cables, if necessary.
ADJUSTMENTS - VALVE BODY
CONTROL PRESSURE ADJUSTMENTS
There are two control pressure adjustments on the
valve body;
²Line Pressure
²Throttle Pressure
Line and throttle pressures are interdependent
because each affects shift quality and timing. As a
result, both adjustments must be performed properly
and in the correct sequence. Adjust line pressure first
and throttle pressure last.
Fig. 313 Solenoid Harness Routing
1 - OVERDRIVE/CONVERTER SOLENOID WIRE HARNESS
2 - 3-4 ACCUMULATOR COVER PLATE
Fig. 314 Valve Body Harness Connector O-Ring Seal
1 - CONNECTOR O-RINGS
2 - VALVE BODY HARNESS CONNECTOR
3 - HARNESS
21 - 818 AUTOMATIC TRANSMISSION - 47REBR/BE
VALVE BODY (Continued)

LINE PRESSURE ADJUSTMENT
Measure distance from the valve body to the inner
edge of the adjusting screw with an accurate steel
scale (Fig. 317).
Distance should be 33.4 mm (1-5/16 in.).
If adjustment is required, turn the adjusting screw
in, or out, to obtain required distance setting.
NOTE: The 33.4 mm (1-5/16 in.) setting is an
approximate setting. Manufacturing tolerances may
make it necessary to vary from this dimension to
obtain desired pressure.
One complete turn of the adjusting screw changes
line pressure approximately 1-2/3 psi (9 kPa).
Turning the adjusting screw counterclockwise
increases pressure while turning the screw clockwise
decreases pressure.THROTTLE PRESSURE ADJUSTMENT
Insert Gauge Tool C-3763 between the throttle
lever cam and the kickdown valve stem (Fig. 318).
Push the gauge tool inward to compress the kick-
down valve against the spring and bottom the throt-
tle valve.
Maintain pressure against kickdown valve spring.
Turn throttle lever stop screw until the screw head
touches throttle lever tang and the throttle lever cam
touches gauge tool.
NOTE: The kickdown valve spring must be fully
compressed and the kickdown valve completely
bottomed to obtain correct adjustment.
Fig. 315 Manual Lever Shaft Seal
1 - 15/16©© SOCKET
2 - SEAL
Fig. 316 Accumulator Piston Components
1 - INNER SPRING
2 - ACCUMULATOR PISTON
3 - OUTER SPRING
4 - SEAL RINGS
Fig. 317 Line Pressure Adjustment
1 - WRENCH
2 - 1±5/16 INCH
Fig. 318 Throttle Pressure Adjustment
1 - HEX WRENCH (IN THROTTLE LEVER ADJUSTING SCREW)
2 - SPECIAL TOOL C-3763 (POSITIONED BETWEEN THROTTLE
LEVER AND KICKDOWN VALVE)
BR/BEAUTOMATIC TRANSMISSION - 47RE 21 - 819
VALVE BODY (Continued)

TRANSFER CASE - NV231HD
TABLE OF CONTENTS
page page
TRANSFER CASE - NV231HD
DESCRIPTION..........................820
OPERATION............................820
DIAGNOSIS AND TESTING................821
TRANSFER CASE.....................821
REMOVAL.............................822
DISASSEMBLY..........................822
CLEANING.............................831
INSPECTION...........................832
ASSEMBLY............................834
INSTALLATION..........................847
SPECIFICATIONS........................848
SPECIAL TOOLS........................849EXTENSION HOUSING BUSHING AND SEAL
REMOVAL.............................850
INSTALLATION..........................850
FLUID
STANDARD PROCEDURE.................851
FLUID DRAIN AND REFILL...............851
FRONT OUTPUT SHAFT SEAL
REMOVAL.............................851
INSTALLATION..........................852
SHIFT LEVER
REMOVAL.............................852
INSTALLATION..........................853
ADJUSTMENTS.........................853
TRANSFER CASE - NV231HD
DESCRIPTION
The NV231HD transfer case is a part-time transfer
case with a low-range gear system. It provides three
operating ranges plus a NEUTRAL position. The low
range position provides a gear reduction ratio of
2.72:1 for increased low speed torque capability.
The synchronizer mechanism consists of a brass
stop ring, synchro hub, and the sliding clutch. The
synchronizer components allow the transfer case to
be shifted between the 2H and 4H operating ranges
while the vehicle is in motion.
The gear cases, retainer and extension are all of
aluminum. Drive sprockets and an interconnecting
drive chain are used to transmit engine torque to the
front/rear propeller shafts. The mainshaft, input gear
and front output shaft are supported by ball and nee-
dle bearings.
IDENTIFICATION
An identification tag (Fig. 1) is attached to the rear
case of every transfer case. The tag provides the
transfer case model number, assembly number, serial
number, and low range ratio.
The transfer case serial number also represents
the date of build.
OPERATION
OPERATING RANGES
Transfer case operating ranges are:
²4x2 (2-wheel drive)
²4x4 (4-wheel drive)
²4 Lo (4-wheel drive low range
Fig. 1 Transfer Case Identification Tag - Typical
1 - I.D. TAG
2 - FILL PLUG
3 - DRAIN PLUG
21 - 820 TRANSFER CASE - NV231HDBR/BE

The 4x2 range is for use on any road surface at
any time.
The 4x4 and 4 Lo ranges are for off road use only.
They are not for use on hard surface roads. The only
exception being when the road surface is covered by
ice and snow.
The low range reduction gear system is operative
in 4 Lo range only. This range is for extra pulling
power in off road situations. Low range reduction
ratio is 2.72:1.
A front axle disconnect system is used to achieve
two-wheel drive mode. The axle disconnect vacuum
motor is actuated by a vacuum switch on the transfer
case. The switch is operated by the transfer case
range rod.
SHIFT MECHANISM
The transfer case is operated by an adjustable floor
mounted shift linkage. The transfer case shift lever
is directly attached to the shift sector. The sector
operates the range and mode forks within the trans-
fer case.
A straight line shift pattern is used with a NEU-
TRAL detent. Lever range positions are imprinted in
the shift knob.
SHIFTING
The synchronizer components allow the transfer
case to be shifted between the 2H and 4H operating
ranges while the vehicle is in motion. The vehicle
must have the transmission placed in NEUTRAL, or
the clutch depressed in the case of a manual trans-
mission, and be moving less than 2-3 MPH when
shifting into the 4L operating range.
DIAGNOSIS AND TESTING - TRANSFER CASE
Before beginning repair on a suspected transfer
case malfunction, check all other driveline compo-
nents beforehand.
The actual cause of a problem may be related to
such items as: front hubs, axles, propeller shafts,
wheels and tires, transmission, or clutch instead. If
all other driveline components are in good condition
and operating properly, refer to the Diagnosis Chart
for further information.
DIAGNOSIS CHART
Condition Possible Cause Correction
Transfer Case difficult to shift or will
not shift into desired range.1) Vehicle speed too great to permit
shifting.1) Stop vehicle and shift into
desired range. Or, reduce speed to
below 3-4 km/h (2-3 mph) before
attempting the shift.
2) If vehicle was operated for an
extended period in 4H on a dry
paved surface, the driveline torque
load may be causing a bind.2) Stop vehicle and shift the
transmission into neutral. Shift the
transfer case to 2H and operate
vehicle in 2H on dry paved
surfaces.
3) Transfer case external shift
linkage binding.3) Lubricate, repair, or replace
linkage bushings, or tighten loose
components as necessary.
4) Insufficient or incorrect lubricant. 4) Drain and refill to edge of fill hole
with MoparTATF +4, type 9602,
Automatic Transmission fluid.
5) Internal components binding,
worn, or damaged.5) Disassemble the transfer case
and replace worn or damaged
components as necessary.
Transfer Case noisy in all operating
ranges.1) Insufficient or incorrect lubricant. 1) Drain and refill to edge of fill hole
with MoparTATF +4, type 9602,
Automatic Transmission fluid.
BR/BETRANSFER CASE - NV231HD 21 - 821
TRANSFER CASE - NV231HD (Continued)

Condition Possible Cause Correction
Noisy in, or jumps out of, four wheel
drive low range.1) Transfer case not completely
engaged in 4L position.1) With the transmission in
NEUTRAL, or the clutch depressed
in the case of a manual
transmission and the vehicle moving
under 3-4 km/h (2-3 mph), shift the
transfer case to NEUTRAL and then
shift into the 4L position.
2) Shift linkage out of adjustment. 2) Adjust linkage.
3) Shift linkage loose or binding. 3) Tighten, lubricate, or repair
linkage as necessary.
4) Range fork damaged, inserts
worn, or fork is binding on the shift
rail.4) Disassemble unit and repair as
necessary.
5) Low range gear worn or
damaged.5) Disassemble unit and repair as
necessary.
Lubricant leaking from output shaft
seal or vent.1) Transfer case overfilled. 1) Drain lubricant to the correct
level.
2) Vent closed or restricted. 2) Clear or replace vent as
necessary.
3) Output shaft seals damaged or
installed incorrectly.3) Replace seal as necessary.
Check to ensure that another
component, the propeller shaft slip
yoke for example, is not causing
damage to seal.
Abnormal tire wear. 1) Extended operation on hard, dry
surfaces in the 4H position.1) Operate vehicle in the 2H
position on hard, dry surfaces.
REMOVAL
(1) Raise and support vehicle.
(2) Remove skid plate, if equipped. (Refer to 13 -
FRAMES & BUMPERS/FRAME/TRANSFER CASE
SKID PLATE - REMOVAL)
(3) Position drain oil container under transfer
case.
(4) Remove transfer case drain plug and drain
lubricant into container.
(5) Disconnect vent hose and vacuum harness at
transfer case switch.
(6) Disconnect shift rod from grommet in transfer
case shift lever, or from floor shift arm whichever
provides easy access. Use channel lock style pliers to
press rod out of lever grommet.
(7) Support transmission with jack stand.
(8) Remove rear crossmember.
(9) Mark front and rear propeller shafts for assem-
bly reference.(10) Remove front and rear propeller shafts. (Refer
to 3 - DIFFERENTIAL & DRIVELINE/PROPELLER
SHAFT/PROPELLER SHAFT - REMOVAL)
(11) Support transfer case with suitable jack.
Secure transfer case to jack with safety chains.
(12) Remove nuts attaching transfer case to trans-
mission.
(13) Move transfer case assembly rearward until
free of transmission output shaft.
(14) Lower jack and move transfer case from
under vehicle.
DISASSEMBLY
Position transfer case in a shallow drain pan.
Remove drain plug and drain any remaining lubri-
cant remaining in case.
21 - 822 TRANSFER CASE - NV231HDBR/BE
TRANSFER CASE - NV231HD (Continued)

REAR EXTENSION, RETAINER, AND REAR CASE
(1) Remove rear extension bolts (Fig. 2).
(2) Remove rear extension housing (Fig. 3). Tap
extension once or twice with a plastic mallet to break
sealer bead and loosen it.
(3) Remove output bearing retaining ring with
heavy duty snap-ring pliers (Fig. 4).
(4) Remove rear retainer bolts (Fig. 5).
(5) Loosen rear retainer with pry bar placed under
flange (Fig. 6).
(6) Remove rear retainer and output bearing as
assembly (Fig. 7).
COMPANION FLANGE AND SHIFT LEVER
(1) Shift transfer case into NEUTRAL.
(2) Remove companion flange nut (Fig. 8). Discard
nut after removal. It is not reusable.
Fig. 2 Rear Extension Bolt Removal
1 - SOCKET
2 - REAR EXTENSION
Fig. 3 Rear Extension Housing Removal
1 - SEAL
2 - REAR EXTENSION HOUSING
3 - REAR RETAINER
Fig. 4 Removing Output Bearing Retaining Ring
1 - OUTPUT BEARING
2 - RETAINING RING
3 - REAR RETAINER
Fig. 5 Removing Rear Extension Bolts
1 - SOCKET
2 - REAR RETAINER
Fig. 6 Loosening Rear Retainer
1 - REAR RETAINER
2 - FLANGE
3-PRYTOOL
BR/BETRANSFER CASE - NV231HD 21 - 823
TRANSFER CASE - NV231HD (Continued)

(3) Remove companion flange from front output
shaft. Use a suitable puller if flange can not be
removed by hand.
(4) Remove companion flange rubber seal from
front output shaft (Fig. 9).(5) Remove nut and washer that retain shift lever
to sector shaft. Then remove shift lever from shaft
(Fig. 10).
FRONT OUTPUT SHAFT AND DRIVE CHAIN
(1) Remove output bearing retaining ring with
heavy duty snap-ring pliers.
(2) Remove output shaft bearing.
(3) Note position of bolts that attach rear case to
front case (Fig. 11). Some bolts/studs at ends of case
require flat washers. Mark position of these bolts
with paint or scriber.
(4) Remove rear case-to-front case bolts.
Fig. 7 Rear Retainer Removal
1 - OUTPUT BEARING
2 - REAR RETAINER
Fig. 8 Removing Companion Flange Nut
1 - COMPANION FLANGE
2 - SOCKET
Fig. 9 Companion Flange Seal Removal
1 - FLANGE SEAL
Fig. 10 Shift Lever Removal
1 - SHIFT LEVER
2 - NUT/WASHER
Fig. 11 Removing Case Attaching Bolts
1 - REAR CASE
2 - STUD
3 - NUT AND WASHER
4 - SOCKET
21 - 824 TRANSFER CASE - NV231HDBR/BE
TRANSFER CASE - NV231HD (Continued)

(5) Loosen rear case with pry tool to break sealer
bead. Insert tool in slot at each end of case (Fig. 12).
(6) Unseat rear case from alignment dowels (Fig.
13).(7) Remove rear case and oil pump assembly from
front case.
(8) Remove shift rail cup and spring (Fig. 14).
(9) Remove front sprocket retaining ring (Fig. 15).
Fig. 12 Loosening Rear Case (Breaking Sealer
Bead)
1 - SLOT
2 - REAR CASE
3-PRYTOOL
Fig. 13 Removing Rear Case From Alignment
Dowels
1 - CASE DOWELS (2)
2 - REAR CASE
Fig. 14 Shift Rail Cup And Spring Removal
1 - SHIFT RAIL
2 - SPRING
3 - CUP
Fig. 15 Removing Front Sprocket Retaining Ring
1 - FRONT SPROCKET
2 - RETAINING RING
3 - FRONT OUTPUT SHAFT
BR/BETRANSFER CASE - NV231HD 21 - 825
TRANSFER CASE - NV231HD (Continued)