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SECTION 7D2
NEW PROCESS 241 TRANSFER CASE
CONTENTS
SUBJECT
PAGE
New Process 241 Transfer C a s e ...........................................................................................................................................7D2- 1
D escrip tio n ............................................................................................................................................................................... 7D2- 1
Disassembly of Transfer C a s e ............................................................................................................................................... 7D2- 4
External C o m p o n e n ts ...........................................................................................................................................................7D2- 4
Mainshaft Extension and Oil Pump H ousing........................................... ...................................................................... 7D2- 4
Internal C om ponents............................................................................................................................................................. 7D2- 4
Cleaning and In spectio n ........................................................................................................................................................... 7D2- 7
Assembly . . . ................................................................................................................................................................................7D2- 8
Bearing and Seal Replacem ent........................................................................................................................................... 7D2- 8
Internal C om ponents............................................................................................................................................................. 7D2- 9
External C o m p o n e n ts ........................................................................................................................................................... 7D2-10
Specifications ..............................................................................................................................................................................7D2-14
Special T o o ls ................................................................................................................................................................................7D2-14
NEW PROCESS 241 TRANSFER CASE
DESCRIPTION
The Model 241 transfer case is an aluminum case,
chain drive, four position unit providing four-wheel drive
high and low ranges, a two-wheel high range, and a
neutral position. The model 241 is a part-time four-wheel
drive unit. Torque input in four-wheel high and low ranges
is undifferentiated. The range positions on the Model 241
are selected by a floor mounted gearshift lever.
The case is a two-piece aluminum case containing front
and rear outp ut shafts, two drive sprockets, a shift
mechanism and a planetary gear assembly. The drive
sprockets are connected and operated by the drive chain.
The planetary assembly which consists of a six pinion
carrier and an annulus gear provide the four-wheel drive
low range when engaged. Reduction ratio is 2.72:1 in this
range (figures 1 and 2).
IDENTIFICATION
An identification tag is attached to the rear half of the
transfer case (figure 3). This tag provides the transfer
case m odel number, low range reduction ratio, and
a sse m b ly num ber. The in fo rm a tio n on th is tag is
necessary for servicing information. If the tag is removed
or becomes dislodged during service operations, it should
be reattached using an adhesive sealant such as Loctite
242, or equivalent.
POWER FLOW
In all drive range positions input torque is transm itted to
the transfer case gear train through the transfer case
input gear.
In 2H range, torque flows from the input gear to the
range shift hub and main shaft. Torque flow continues
through the slip yoke which is splined to the mainshaft,
and finally to the rear propeller shaft and axle. In 2H
range, the mode synchronizer remains in the neutral
position and does not lock the drive sprocket to the
mainshaft. As a result, torque is not transferred to the
driven sprocket.
In 4H range, input torque from the input gear is
transmitted to the mainshaft in exactly the same fashion
as in 2H range. However, in 4H position, the mode
synchronizer sleeve is shifted into engagem ent with the
clutch teeth of the drive sprocket. This locks the drive
sprocket to the m ainshaft through the synchronizer.
Torque is transm itted through the drive sprocket to the
driven sprocket by the connecting drive chain. Since the
front output shaft is splined to the driven sprocket, torque
flows through the front output shaft to the front propeller
shaft and axle resulting in high range four-wheel drive.
In 4L range, the path of torque through the transfer
case is exactly the same as in 4H range but with one
major difference. In 4L range the range shift hub is shifted
into engagem ent with the planetary carrier. This causes
the input gear to rotate the planetary pinions inside the
annulus gear, causing the planetary carrier, range shift
hub and mainshaft to rotate at a gear reduction ration of
2.72:1.
Summary of Contents for 1989 Light Duty Truck
Page 1: ...vr V Light Duty Truck Unit Repair Manual...
Page 2: ......
Page 11: ...GENERAL INFORMATION OA 5 Figure 8 RV Models...
Page 13: ...GENERAL INFORMATION OA 7 Figure 11 ST Models...
Page 18: ......
Page 44: ......
Page 76: ...1B3 18 R 4 AIR CONDITIONING COMPRESSOR N...
Page 114: ......
Page 162: ......
Page 176: ...4B3 14 91 2 INCH RING GEAR...
Page 192: ...4B5 4 DANA REAR AXLES Figure 4 Spreading the Differential Case Figure 7 Removing the Ring Gear...
Page 218: ......
Page 220: ...4B6 2 12 INCH RING GEAR ROCKWELL F 04734 Figure 1 Rear Axle Components...
Page 229: ...12 INCH RING GEAR ROCKWELL 4B6 11 SPECIAL TOOLS Special Tools...
Page 230: ...4B6 12 12 INCH RING...
Page 240: ...4B7 10 LOCKING DIFFERENTIALS SPECIAL TOOLS Special Tools...
Page 260: ...4C2 6 93 4 INCH RING GEAR FRONT AXLE Figure 16 Removing the Pinion Inner Bearing...
Page 273: ...T TRUCK FRONT AXLE 4C3 3 F 05785 Figure 1 Axle Components...
Page 291: ...K TRUCK FRONT AXLE 4C4 3 Figure 1 Front Axle Com ponents K 15 25 Models...
Page 293: ...K TRUCK FRONT AXLE 4C4 5 Figure 3 Front Axle Com ponents K35 Models...
Page 318: ...C4 30 K TRUCK FBOHT AXLE...
Page 334: ......
Page 361: ...2 5 LITER L4 ENGINE 6A1 5 Figure 3 Cylinder Head Manifolds and Components...
Page 363: ...2 5 LITER L4 ENGINE 6A1 7 F 05715 Figure 5 Block and Components...
Page 395: ...2 8 LITER V 6 6A2 3 Figure 1 Engine Lubrication Diagram...
Page 396: ...6A2 4 2 8 LITER V 6 Figure 2 Engine Lubrication Diagram...
Page 424: ...6A2 32 2 8 LITER V 6...
Page 427: ...I 4 3 LITER V 6 6A3 3 Figure 1 Engine Lubrication Diagram B 07857...
Page 451: ...4 3 LITER V 6 6A3 27 SPECIFICATIONS ENGINE SPECIFICATIONS F 6344...
Page 457: ...4 8 LITER L6 6A4 3 Figure 2 Lubrication Diagram Front View...
Page 460: ...6A4 6 4 8 LITER L6 C 1 107 112 fK 108 3 109 165 129 B 05056 Figure 5 Block and Components...
Page 490: ...Ml...
Page 493: ...V8 ENGINE 6A5 3 Figure 1 Lubrication Diagram 5 0L and 5 7L Engines...
Page 494: ...6A5 4 V8 ENGINE Figure 2 Lubrication Diagram 5 0L and 5 7L Engines...
Page 530: ...6A5 40 V8 ENGINE Figure 81 Exhaust Manifold 7 4L Engines Figure 82 Water Pumps and Components...
Page 571: ...6 2 LITER DIESEL 6A7 35 Figure 58 Vacuum Pump Installed...
Page 576: ......
Page 582: ...6C1 6 MODEL 1MEF CARBURETOR Figure 9 Monojet Model 1MEF...
Page 604: ...6C2 6 MODEL M4MEF CARBURETOR Figure 9 Model M4MEF...
Page 640: ...6C4 8 MODEL 700 THROTTLE BODY...
Page 652: ...nmm...
Page 672: ......
Page 693: ...DISTRIBUTORS 6D5 13 Figure 27 Testing the Pickup Coil Figure 28 Testing the Ignition Coil...
Page 696: ......
Page 698: ...7A1 2 700 R4 AUTOMATIC TRANSMISSION Figure 1 Case and External Parts J H 0 0 5 3 7 0 0 R 4 R 2...
Page 745: ...700 R4 AUTOMATIC TRANSMISSION 7A1 49...
Page 762: ...7A2 2 400 475 AUTOMATIC TRANSMISSION Figure 1 Case and External Parts H H 0021 400 R 3...
Page 773: ...400 475 AUTOMATIC TRANSMISSION 7A2 13 Figure 29 Internal Parts H H 0 0 4 3 4 0 0 R 2...
Page 797: ...400 475 AUTOMATIC TRANSMISSION 7A2 37 Figure 93 Control Valve Assem bly...
Page 803: ...400 475 AUTOMATIC TRANSMISSION 7A2 43 Figure 104 Bushing Replacement Procedure...
Page 808: ...J c I i sal...
Page 838: ......
Page 840: ......
Page 842: ......
Page 850: ...7B1 12 HM 290 MANUAL TRANSMISSION J i t i a x V L...
Page 856: ...7B1 18 HM 290 MANUAL TRANSMISSION...
Page 892: ...7B1 54 HM 290 MANUAL TRANSMISSION Figure 93 Special Tools...
Page 897: ...HM 117 TRANSMISSION 7B2 5...
Page 901: ...HM 117 TRANSMISSION 7B2 9 B 05180 Figure 17 Installing the 1st and 2nd Synchronizer...
Page 912: ...20 HM...
Page 924: ...7B3 12 NEW PROCESS TRANSMISSION SPECIAL TOOLS...
Page 927: ...BORG WARNER TRANSMISSIONS 7B4 3 Figure 2 77 mm Transmission and Components...
Page 940: ...i ii iii m i in m i...
Page 944: ...7D1 4 TRANSFER CASE FO 5688 Figure 3 NP205 Transfer Case...
Page 952: ...7D1 12 TRANSFER CASE...
Page 963: ...NEW PROCESS 241 TRANSFER CASE 7D2 11 Figure 17 Oil Pump Pickup Screen Doweled Case Holes...
Page 964: ...7D2 12 NEW PROCESS 241 TRANSFER CASE Figure 18 NP 241 Transfer Case Cut Away...
Page 978: ......
Page 981: ...BORG WARNER 1370 TRANSFER CASE 7D4 3 J...
Page 992: ...7D4 14 BORG WARNER 1370 TRANSFER CASE Figure 26 Installing the Rear Output Yoke...
Page 993: ...BORG WARNER 1370 TRANSFER CASE 7D4 15 Figure 27 BW 1370 Transfer Case...
Page 997: ......
Page 998: ...X 8937...