wheel DODGE RAM 2001 Service Repair Manual
[x] Cancel search | Manufacturer: DODGE, Model Year: 2001, Model line: RAM, Model: DODGE RAM 2001Pages: 2889, PDF Size: 68.07 MB
Page 2294 of 2889

The rear servo and governor pressure ports are at
the right rear of the transmission case. The overdrive
clutch pressure port is at the left rear of the case.
Test One - Transmission In Manual Low
NOTE: This test checks pump output, pressure reg-
ulation, and condition of the rear clutch and servo
circuit. Both test gauges are required for this test.
(1) Connect tachometer to engine. Position tachom-
eter so it can be observed from driver seat if helper
will be operating engine. Raise vehicle on hoist that
will allow rear wheels to rotate freely.
(2) Connect 100 psi Gauge C-3292 to accumulator
port. Then connect 300 psi Gauge C-3293-SP to rear
servo port.
(3) Disconnect throttle and gearshift cables from
levers on transmission valve body manual shaft.
(4) Have helper start and run engine at 1000 rpm.
(5) Move transmission shift lever fully forward
into 1 range.(6) Gradually move transmission throttle lever
from full forward to full rearward position and note
pressures on both gauges:
²Line pressure at accumulator port should be
54-60 psi (372-414 kPa) with throttle lever forward
and gradually increase to 90-96 psi (621-662 kPa) as
throttle lever is moved rearward.
²Rear servo pressure should be same as line pres-
sure within 3 psi (20.68 kPa).
Test Two - Transmission In 2 Range
NOTE: This test checks pump output, line pressure
and pressure regulation. Use 100 psi Test Gauge
C-3292 for this test.
(1) Leave vehicle in place on hoist and leave Test
Gauge C-3292 connected to accumulator port.
(2) Have helper start and run engine at 1000 rpm.
(3) Move transmission shift lever one detent rear-
ward from full forward position. This is 2 range.
(4) Move transmission throttle lever from full for-
ward to full rearward position and read pressure on
gauge.
(5) Line pressure should be 54-60 psi (372-414
kPa) with throttle lever forward and gradually
increase to 90-96 psi (621-662 kPa) as lever is moved
rearward.
Test Three - Transmission In D Range Third Gear
NOTE: This test checks pressure regulation and
condition of the clutch circuits. Both test gauges
are required for this test.
(1) Turn OD switch off.
(2) Leave vehicle on hoist and leave Gauge C-3292
in place at accumulator port.
(3) Move Gauge C-3293-SP over to front servo port
for this test.
(4) Have helper start and run engine at 1600 rpm
for this test.
(5) Move transmission shift lever two detents rear-
ward from full forward position. This is D range.
(6) Read pressures on both gauges as transmission
throttle lever is gradually moved from full forward to
full rearward position:
²Line pressure at accumulator in D range third
gear, should be 54-60 psi (372-414 kPa) with throttle
lever forward and increase as lever is moved rear-
ward.
²Front servo pressure in D range third gear,
should be within 3 psi (21 kPa) of line pressure up to
kickdown point.
Fig. 9 Pressure Test Port Locations
1 - REAR SERVO TEST PORT
2 - GOVERNOR TEST PORT
3 - ACCUMULATOR TEST PORT
4 - FRONT SERVO TEST PORT
5 - OVERDRIVE CLUTCH TEST PORT
BR/BEAUTOMATIC TRANSMISSION - 47RE 21 - 659
AUTOMATIC TRANSMISSION - 47RE (Continued)
Page 2295 of 2889

Test Four - Transmission In Reverse
NOTE: This test checks pump output, pressure reg-
ulation and the front clutch and rear servo circuits.
Use 300 psi Test Gauge C-3293-SP for this test.
(1) Leave vehicle on hoist and leave gauge C-3292
in place at accumulator port.
(2) Move 300 psi Gauge C-3293-SP back to rear
servo port.
(3) Have helper start and run engine at 1600 rpm
for test.
(4) Move transmission shift lever four detents
rearward from full forward position. This is Reverse
range.
(5) Move transmission throttle lever fully forward
then fully rearward and note reading at Gauge
C-3293-SP.
(6) Pressure should be 145 - 175 psi (1000-1207
kPa) with throttle lever forward and increase to 230 -
280 psi (1586-1931 kPa) as lever is gradually moved
rearward.
Test Five - Governor Pressure
NOTE: This test checks governor operation by mea-
suring governor pressure response to changes in
vehicle speed. It is usually not necessary to check
governor operation unless shift speeds are incor-
rect or if the transmission will not downshift. The
test should be performed on the road or on a hoist
that will allow the rear wheels to rotate freely.
(1) Move 100 psi Test Gauge C-3292 to governor
pressure port.
(2) Move transmission shift lever two detents rear-
ward from full forward position. This is D range.
(3) Have helper start and run engine at curb idle
speed. Then firmly apply service brakes so wheels
will not rotate.
(4) Note governor pressure:
²Governor pressure should be no more than 20.6
kPa (3 psi) at curb idle speed and wheels not rotat-
ing.²If pressure exceeds 20.6 kPa (3 psi), a fault
exists in governor pressure control system.
(5) Release brakes, slowly increase engine speed,
and observe speedometer and pressure test gauge (do
not exceed 30 mph on speedometer). Governor pres-
sure should increase in proportion to vehicle speed.
Or approximately 6.89 kPa (1 psi) for every 1 mph.
(6) Governor pressure rise should be smooth and
drop back to no more than 20.6 kPa (3 psi), after
engine returns to curb idle and brakes are applied to
prevent wheels from rotating.
(7) Compare results of pressure test with analysis
chart.
Test Six - Transmission In Overdrive Fourth Gear
NOTE: This test checks line pressure at the over-
drive clutch in fourth gear range. Use 300 psi Test
Gauge C-3293-SP for this test. The test should be
performed on the road or on a chassis dyno.
(1) Remove tachometer; it is not needed for this
test.
(2) Move 300 psi Gauge to overdrive clutch pres-
sure test port. Then remove other gauge and reinstall
test port plug.
(3) Lower vehicle.
(4) Turn OD switch on.
(5) Secure test gauge so it can be viewed from
drivers seat.
(6) Start engine and shift into D range.
(7) Increase vehicle speed gradually until 3-4 shift
occurs and note gauge pressure.
(8) Pressure should be 469-496 kPa (68-72 psi)
with closed throttle and increase to 620-827 kPa (90-
120 psi) at 1/2 to 3/4 throttle. Note that pressure can
increase to around 896 kPa (130 psi) at full throttle.
(9) Return to shop or move vehicle off chassis
dyno.
21 - 660 AUTOMATIC TRANSMISSION - 47REBR/BE
AUTOMATIC TRANSMISSION - 47RE (Continued)
Page 2347 of 2889

WIDE OPEN THROTTLE OPERATION
In wide-open throttle (WOT) mode, adaptive memory
in the PCM assures that up-shifts occur at the prepro-
grammed optimum speed. WOT operation is determined
from the throttle position sensor, which is also a part of
the emission control system. The initial setting for the
WOT upshift is below the optimum engine speed. As
WOT shifts are repeated, the PCM learns the time
required to complete the shifts by comparing the engine
speed when the shifts occur to the optimum speed. After
each shift, the PCM adjusts the shift point until the
optimum speed is reached. The PCM also considers
vehicle loading, grade and engine performance changes
due to high altitude in determining when to make WOT
shifts. It does this by measuring vehicle and engine
acceleration and then factoring in the shift time.
TRANSFER CASE LOW RANGE OPERATION
On four-wheel drive vehicles operating in low
range, the engine can accelerate to its peak more
rapidly than in Normal range, resulting in delayed
shifts and undesirable engine9flare.9The low range
governor pressure curve is also higher than normal
to initiate upshifts sooner. The PCM compares elec-
tronic vehicle speed signal used by the speedometer
to the transmission output shaft speed signal to
determine when the transfer case is in low range.
REMOVAL
(1) Hoist and support vehicle on safety stands.
(2) Remove transmission fluid pan and filter.
(3) Disengage wire connectors from pressure sen-
sor and solenoid (Fig. 71).
(4) Remove screws holding pressure solenoid
retainer to governor body.(5) Separate solenoid retainer from governor (Fig.
72).
(6) Pull solenoid from governor body (Fig. 73).
(7) Pull pressure sensor from governor body.
(8) Remove bolts holding governor body to valve
body.
Fig. 71 Governor Solenoid And Pressure Sensor
1 - PRESSURE SENSOR
2 - PRESSURE SOLENOID
3 - GOVERNOR
Fig. 72 Pressure Solenoid Retainer
1 - PRESSURE SOLENOID RETAINER
2 - GOVERNOR
Fig. 73 Pressure Solenoid and O-ring
1 - PRESSURE SOLENOID
2 - O-RING
3 - GOVERNOR
21 - 712 AUTOMATIC TRANSMISSION - 47REBR/BE
ELECTRONIC GOVERNOR (Continued)
Page 2386 of 2889

(6) Install selective spacer on intermediate shaft, if
removed. Spacer goes in groove just rearward of
shaft rear splines (Fig. 177).
(7) Install thrust bearing in overdrive unit sliding
hub. Use petroleum jelly to hold bearing in position.
CAUTION: Be sure the shoulder on the inside diam-
eter of the bearing is facing forward.
(8) Verify that splines in overdrive planetary gear
and overrunning clutch hub are aligned with Align-
ment Tool 6227-2. Overdrive unit cannot be installed
if splines are not aligned. If splines have rotated out
of alignment, unit will have to be disassembled to
realign splines.
(9) Carefully slide Alignment Tool 6227-2 out of
overdrive planetary gear and overrunning clutch
splines.
(10) Raise overdrive unit and carefully slide it
straight onto intermediate shaft. Insert park rod into
park lock reaction plug at same time. Avoid tilting
overdrive during installation as this could cause
planetary gear and overrunning clutch splines to
rotate out of alignment. If this occurs, it will be nec-
essary to remove and disassemble overdrive unit to
realign splines.
(11) Work overdrive unit forward on intermediate
shaft until seated against transmission case.
(12) Install bolts attaching overdrive unit to trans-
mission unit. Tighten bolts in diagonal pattern to 34
N´m (25 ft-lbs).
(13) Connect the transmission speed sensor and
overdrive wiring connectors.
(14) Install the transfer case, if equipped.
(15) Align and install rear propeller shaft, if nec-
essary. (Refer to 3 - DIFFERENTIAL & DRIVELINE/
PROPELLER SHAFT/PROPELLER SHAFT -
INSTALLATION)OVERRUNNING CLUTCH
CAM/OVERDRIVE PISTON
RETAINER
DESCRIPTION
The overrunning clutch (Fig. 178) consists of an
inner race, an outer race (or cam), rollers and
springs, and the spring retainer. The number of roll-
ers and springs depends on what transmission and
which overrunning clutch is being dealt with.
OPERATION
As the inner race is rotated in a clockwise direction
(as viewed from the front of the transmission), the
race causes the rollers to roll toward the springs,
causing them to compress against their retainer. The
compression of the springs increases the clearance
between the rollers and cam. This increased clear-
ance between the rollers and cam results in a free-
wheeling condition. When the inner race attempts to
rotate counterclockwise, the action causes the rollers
to roll in the same direction as the race, aided by the
pushing of the springs. As the rollers try to move in
the same direction as the inner race, they are
wedged between the inner and outer races due to the
design of the cam. In this condition, the clutch is
locked and acts as one unit.
DISASSEMBLY
(1) Remove the overdrive piston (Fig. 179).
(2) Remove the overdrive piston retainer bolts.
(3) Remove overdrive piston retainer.
Fig. 177 Intermediate Shaft Selective Spacer
Location
1 - SELECTIVE SPACER
2 - SPACER GROOVE
3 - INTERMEDIATE SHAFT
Fig. 178 Overrunning Clutch
1 - OUTER RACE (CAM)
2 - ROLLER
3 - SPRING
4 - SPRING RETAINER
5 - INNER RACE (HUB)
BR/BEAUTOMATIC TRANSMISSION - 47RE 21 - 751
OVERDRIVE UNIT (Continued)
Page 2412 of 2889

OPERATION
The converter impeller (Fig. 235) (driving member),
which is integral to the converter housing and bolted
to the engine drive plate, rotates at engine speed.
The converter turbine (driven member), which reacts
from fluid pressure generated by the impeller, rotates
and turns the transmission input shaft.
TURBINE
As the fluid that was put into motion by the impel-
ler blades strikes the blades of the turbine, some of
the energy and rotational force is transferred into the
turbine and the input shaft. This causes both of them
(turbine and input shaft) to rotate in a clockwise
direction following the impeller. As the fluid is leav-
ing the trailing edges of the turbine's blades it con-
tinues in a ªhinderingº direction back toward the
impeller. If the fluid is not redirected before it strikes
the impeller, it will strike the impeller in such a
direction that it would tend to slow it down.
STATOR
Torque multiplication is achieved by locking the
stator's over-running clutch to its shaft (Fig. 236).
Under stall conditions (the turbine is stationary), the
oil leaving the turbine blades strikes the face of the
stator blades and tries to rotate them in a counter-
clockwise direction. When this happens the overrun-
ning clutch of the stator locks and holds the stator
from rotating. With the stator locked, the oil strikes
the stator blades and is redirected into a ªhelpingº
direction before it enters the impeller. This circula-
tion of oil from impeller to turbine, turbine to stator,
and stator to impeller, can produce a maximum
torque multiplication of about 2.4:1. As the turbine
begins to match the speed of the impeller, the fluid
that was hitting the stator in such as way as to
cause it to lock-up is no longer doing so. In this con-
dition of operation, the stator begins to free wheel
and the converter acts as a fluid coupling.
Fig. 235 Torque Converter Fluid Operation
1 - APPLY PRESSURE 3 - RELEASE PRESSURE
2 - THE PISTON MOVES SLIGHTLY FORWARD 4 - THE PISTON MOVES SLIGHTLY REARWARD
BR/BEAUTOMATIC TRANSMISSION - 47RE 21 - 777
TORQUE CONVERTER (Continued)
Page 2413 of 2889

TORQUE CONVERTER CLUTCH (TCC)
The torque converter clutch is hydraulically
applied and is released when fluid is vented from the
hydraulic circuit by the torque converter control
(TCC) solenoid on the valve body. The torque con-
verter clutch is controlled by the Powertrain Control
Module (PCM). The torque converter clutch engages
in fourth gear, and in third gear under various con-
ditions, such as when the O/D switch is OFF, when
the vehicle is cruising on a level surface after the
vehicle has warmed up. The torque converter clutch
will disengage momentarily when an increase in
engine load is sensed by the PCM, such as when the
vehicle begins to go uphill or the throttle pressure is
increased.
REMOVAL
(1) Remove transmission and torque converter
from vehicle.
(2) Place a suitable drain pan under the converter
housing end of the transmission.
CAUTION: Verify that transmission is secure on the
lifting device or work surface, the center of gravity
of the transmission will shift when the torque con-
verter is removed creating an unstable condition.
The torque converter is a heavy unit. Use caution
when separating the torque converter from the
transmission.
(3) Pull the torque converter forward until the cen-
ter hub clears the oil pump seal.(4) Separate the torque converter from the trans-
mission.
INSTALLATION
Check converter hub and drive notches for sharp
edges, burrs, scratches, or nicks. Polish the hub and
notches with 320/400 grit paper or crocus cloth if nec-
essary. The hub must be smooth to avoid damaging
the pump seal at installation.
(1) Lubricate oil pump seal lip with transmission
fluid.
(2) Place torque converter in position on transmis-
sion.
CAUTION: Do not damage oil pump seal or bushing
while inserting torque converter into the front of the
transmission.
(3) Align torque converter to oil pump seal open-
ing.
(4) Insert torque converter hub into oil pump.
(5) While pushing torque converter inward, rotate
converter until converter is fully seated in the oil
pump gears.
(6) Check converter seating with a scale and
straightedge (Fig. 237). Surface of converter lugs
should be 19mm (0.75 in.) to the rear of the straight-
edge when converter is fully seated.
(7) If necessary, temporarily secure converter with
C-clamp attached to the converter housing.
(8) Install the transmission in the vehicle.
(9) Fill the transmission with the recommended
fluid.
TORQUE CONVERTER
DRAINBACK VALVE
DESCRIPTION
The drainback valve is located in the transmission
cooler outlet (pressure) line.
OPERATION
The valve prevents fluid from draining from the
converter into the cooler and lines when the vehicle
is shut down for lengthy periods. Production valves
have a hose nipple at one end, while the opposite end
is threaded for a flare fitting. All valves have an
arrow (or similar mark) to indicate direction of flow
through the valve.
STANDARD PROCEDURE - TORQUE
CONVERTER DRAINBACK VALVE
The converter drainback check valve is located in
the cooler outlet (pressure) line near the radiator
tank. The valve prevents fluid drainback when the
Fig. 236 Stator Operation
1 - DIRECTION STATOR WILL FREE WHEEL DUE TO OIL
PUSHING ON BACKSIDE OF VANES
2 - FRONT OF ENGINE
3 - INCREASED ANGLE AS OIL STRIKES VANES
4 - DIRECTION STATOR IS LOCKED UP DUE TO OIL PUSHING
AGAINST STATOR VANES
21 - 778 AUTOMATIC TRANSMISSION - 47REBR/BE
TORQUE CONVERTER (Continued)
Page 2455 of 2889

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
Page 2456 of 2889

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)
Page 2457 of 2889

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)
Page 2490 of 2889

TRANSFER CASE - NV241LD
TABLE OF CONTENTS
page page
TRANSFER CASE - NV241LD
DESCRIPTION..........................855
OPERATION............................855
DIAGNOSIS AND TESTING................856
TRANSFER CASE.....................856
REMOVAL.............................858
DISASSEMBLY..........................858
CLEANING.............................866
INSPECTION...........................867
ASSEMBLY............................869
INSTALLATION..........................882
SPECIFICATIONS........................883
SPECIAL TOOLS........................884EXTENSION HOUSING BUSHING AND SEAL
REMOVAL.............................885
INSTALLATION..........................885
FLUID
STANDARD PROCEDURE.................885
FLUID DRAIN AND REFILL...............885
FRONT OUTPUT SHAFT SEAL
REMOVAL.............................886
INSTALLATION..........................886
SHIFT LEVER
REMOVAL.............................887
INSTALLATION..........................888
ADJUSTMENTS.........................888
TRANSFER CASE - NV241LD
DESCRIPTION
The NV241LD 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:
²2H (2-wheel drive)
²4H (4-wheel drive)²4LO (4-wheel drive low range
The 2H range is for use on any road surface at any
time.
The 4H and 4LO 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 4LO 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
Fig. 1 Transfer Case Identification Tag - Typical
1 - I.D. TAG
2 - FILL PLUG
3 - DRAIN PLUG
BR/BETRANSFER CASE - NV241LD 21 - 855