Page 2254 of 2627
(11) Remove range fork and hub as an assembly
(Fig. 26). Note fork position for installation reference.
(12) Remove the shift sector (Fig. 27).MAINSHAFT
(1) Remove the clutch gear (Fig. 28) from the out-
put shaft.
(2) Remove the mode hub retaining ring (Fig. 29)
from the mainshaft.
Fig. 29 Remove Mode Hub Retaining Ring
1 - MAINSHAFT
2 - MODE HUB
3 - RETAINING RING
Fig. 26 Range Fork And Hub Removal
1 - RANGE HUB
2 - RANGE FORK
Fig. 27 Remove Shift Sector
1 - SHIFT SECTOR
Fig. 28 Remove Clutch Gear
1 - OUTPUT SHAFT
2 - CLUTCH GEAR
3 - MODE HUB
DRTRANSFER CASE - NV273 21 - 551
TRANSFER CASE - NV273 (Continued)
Page 2255 of 2627
(3) Remove the mode hub (Fig. 30) from the main-
shaft.
(4) Remove the drive sprocket drive hub (Fig. 31)
from the mainshaft.INPUT AND PLANETARY GEAR
(1) Remove input gear seal with suitable screw
and slide hammer.
(2) Remove input gear retaining ring (Fig. 32) with
heavy duty snap-ring pliers.
(3) Place front case in horizontal position. Then
remove input gear and low range gear as an assem-
bly (Fig. 33). Tap gear out of bearing with plastic
mallet, if necessary.
Fig. 30 Remove Mode Hub
1 - MAINSHAFT
2 - MODE HUB
Fig. 31 Remove the Drive Sprocket Drive Hub
1 - MAINSHAFT
2 - DRIVE SPROCKET DRIVE HUB
Fig. 32 Remove Input Gear Retaining Ring
1 - INPUT GEAR
2 - RETAINING RING
Fig. 33 Remove Input Planetary Assembly
1 - FRONT CASE
2 - INPUT PLANETARY ASSEMBLY
21 - 552 TRANSFER CASE - NV273DR
TRANSFER CASE - NV273 (Continued)
Page 2256 of 2627
(4) Remove snap-ring that retains input gear in
the low range gear (Fig. 34).
(5) Remove retainer (Fig. 35).
(6) Remove front thrust plate (Fig. 36).
(7) Remove input gear (Fig. 37).
Fig. 37 Remove Input Gear From Planetary
1 - INPUT GEAR
2 - LOW RANGE PLANETARY
Fig. 34 Remove Input Gear Retaining Ring
1 - INPUT GEAR
2 - RETAINING RING
Fig. 35 Remove Input Gear Retainer
1 - INPUT GEAR
2 - RETAINER
Fig. 36 Remove Input Gear Thrust Plate
1 - INPUT GEAR
2 - THRUST PLATE
DRTRANSFER CASE - NV273 21 - 553
TRANSFER CASE - NV273 (Continued)
Page 2257 of 2627

(8) Remove bottom tabbed thrust washer from low
range planetary (Fig. 38).
CLEANING
Clean the transfer case parts with a standard
parts cleaning solvent. Remove all traces of sealer
from the cases and retainers with a scraper and
3MŸ all purpose cleaner. Use compressed air to
remove solvent residue from oil feed passages in the
case halves, retainers, gears, and shafts.
INSPECTION
MAINSHAFT/SPROCKET/HUB INSPECTION
Inspect the splines on the hub and shaft and the
teeth on the sprocket. Minor nicks and scratches can
be smoothed with an oilstone. However, replace any
part that is damaged.
Check the contact surfaces in the sprocket bore
and on the mainshaft. Minor nicks and scratches can
be smoothed with 320-400 grit emery cloth but do not
try to salvage the shaft if nicks or wear is severe.
INPUT GEAR AND PLANETARY CARRIER
Check the teeth on the gear (Fig. 39). Minor nicks
can be dressed off with an oilstone but replace the
gear if any teeth are broken, cracked, or chipped. The
bearing surface on the gear can be smoothed with
300-400 grit emery cloth if necessary.
Examine the carrier body and pinion gears for
wear or damage. Check the pinion gear thrust wash-
ers on the pinon pins for damage. The carrier will
have to be replaced as an assembly if the body, pin-
ion pins, or pinion gears are damaged.
Check the lock ring and both thrust washers for
wear or cracks. Replace them if necessary. Also
replace the lock retaining ring if bent, distorted, or
broken.
Fig. 39 Input Gear And Carrier Components
1 - PLANETARY CARRIER 4 - CARRIER LOCK RING
2 - REAR THRUST WASHER 5 - CARRIER LOCK RETAINING RING
3 - FRONT THRUST WASHER 6 - INPUT GEAR
Fig. 38 Remove Bottom Input Gear Thrust Plate
1 - PLANETARY
2 - THRUST PLATE
21 - 554 TRANSFER CASE - NV273DR
TRANSFER CASE - NV273 (Continued)
Page 2258 of 2627

SHIFT FORKS/HUBS/SLEEVES
Check condition of the shift forks and mode fork
shift rail (Fig. 40). Minor nicks on the shift rail can
be smoothed with 320-400 grit emery cloth.
Inspect the shift fork wear pads (Fig. 41). The
mode and range fork pads are serviceable and can be
replaced if necessary.
Check both of the sleeves for wear or damage,
especially on the interior teeth. Replace the sleeves if
wear or damage is evident.
REAR EXTENSION HOUSING
Inspect the extension housing seal and bushing.
Replace both components if either show any sign of
wear or damage.
FRONT OUTPUT SHAFT AND DRIVE CHAIN
Inspect the shaft threads, sprocket teeth, and bear-
ing surfaces. Minor nicks on the teeth can be
smoothed with an oilstone. Use 320-400 grit emery to
smooth minor scratches on the shaft bearing sur-
faces. Rough threads on the shaft can be chased if
necessary. Replace the shaft if the threads are dam-
aged, bearing surfaces are scored, or if any sprocket
teeth are cracked or broken.
Examine the drive chain and shaft bearings.
Replace the chain and both sprockets if the chain is
stretched, distorted, or if any of the links bind.
Replace the bearings if rough, or noisy.
LOW RANGE ANNULUS GEAR
Inspect annulus gear condition carefully. The gear
is only serviced as part of the front case. If the gear
is damaged, it will be necessary to replace the gear
and front case as an assembly. Do not attempt to
remove the gear (Fig. 42)
FRONT AND REAR CASES
Inspect the cases for wear and damage.
Check case condition. If leaks were a problem, look
for gouges and severe scoring of case sealing sur-
faces. Also make sure the front case mounting studs
are in good condition.
Fig. 40 Shift Forks
1 - RANGE FORK
2 - MODE FORK AND RAIL
3 - MODE SPRING
Fig. 41 Shift Fork And Wear Pad Locations
1 - RANGE FORK
2 - MODE FORK
3 - WEAR PADS (SERVICEABLE)
4 - WEAR PADS (SERVICEABLE)
Fig. 42 Low Range Annulus Gear
1 - FRONT CASE
2 - LOW RANGE ANNULUS GEAR
DRTRANSFER CASE - NV273 21 - 555
TRANSFER CASE - NV273 (Continued)
Page 2259 of 2627

Check the front case mounting studs and vent
tube. The tube can be secured with LoctiteŸ 271 or
680 if loose. The stud threads can be cleaned up with
a die if necessary. Also check condition of the fill/
drain plug threads in the rear case. The threads can
be repaired with a thread chaser or tap if necessary.
Or the threads can be repaired with Helicoiltstain-
less steel inserts if required.
OIL PUMP/OIL PICKUP
Examine the oil pump pickup parts. Replace the
pump if any part appears to be worn or damaged. Do
not disassemble the pump as individual parts are not
available. The pump is only available as a complete
assembly. The pickup screen, hose, and tube are the
only serviceable parts and are available separately.
ASSEMBLY
BEARINGS AND SEALS
(1) Remove the input shaft bearing snap-ring from
the front case half with suitable snap-ring pliers.
(2) Remove the input shaft bearing from the front
case half with Installer 6953 and Handle C-4171
(Fig. 43).
(3) Install the input shaft bearing into the front
case half with Installer 8151 inverted on Handle
C-4171 (Fig. 44).
(4) Install the input shaft bearing snap-ring into
the front case half with suitable snap-ring pliers.(5) Remove the front output shaft front bearing
snap-ring from the front case half.
(6) Using Installer 6953 and Handle C-4171 (Fig.
45), remove the front output shaft front bearing.
Fig. 45 Remove Front Output Shaft Front Bearing
1 - FRONT CASE HALF
2 - HANDLE C-4171
3 - INSTALLER 6953Fig. 43 Remove Input Gear Bearing
1 - FRONT CASE HALF
2 - HANDLE C-4171
3 - INSTALLER 6953
Fig. 44 Install Input Gear Bearing
1 - FRONT CASE HALF
2 - HANDLE C-4171
3 - INSTALLER 8151 (INVERTED)
21 - 556 TRANSFER CASE - NV273DR
TRANSFER CASE - NV273 (Continued)
Page 2260 of 2627
(7) Start front output shaft front bearing in case.
Then seat bearing with Installer 8891 (Fig. 46).
(8) Install front output shaft bearing retaining
ring.
(9) Remove input gear pilot bearing by inserting a
suitably sized drift into the splined end of the input
gear and driving the bearing out with the drift and a
hammer (Fig. 47).(10) Install new pilot bearing with Installer 9035.
(11) Remove the front output shaft rear bearing
with the screw and jaws from Remover L-4454 and
Cup 8148 (Fig. 48).
Fig. 47 Remove Input Gear Cup Bearing
1 - DRIFT
2 - INPUT GEAR
Fig. 48 Front Output Shaft Rear Bearing Removal
1 - REAR CASE
2 - SPECIAL TOOL L-4454-1 AND L-4454-3
3 - SPECIAL TOOL 8148
Fig. 46 Install Front Output Shaft Front Bearing
1 - FRONT CASE HALF
2 - INSTALLER 8891
DRTRANSFER CASE - NV273 21 - 557
TRANSFER CASE - NV273 (Continued)
Page 2261 of 2627
(12) Install new bearing with Tool Handle C-4171
and Installer 8128 (Fig. 49). The bearing bore is
chamfered at the top. Install the bearing so it is
flush with the lower edge of this chamfer (Fig. 50).(13) Remove seal from oil pump with suitable pry
tool.
(14) Install new seal in oil pump with Installer
7888 (Fig. 51).
(15) Remove the rear output shaft bearing snap-
ring (Fig. 52) from the rear case half.
Fig. 52 Remove Rear Output Bearing Outer
Snap-Ring
1 - REAR CASE HALF
2 - REAR OUTPUT SHAFT BEARING
3 - SNAP-RING
Fig. 49 Install Front Output Shaft Rear Bearing
1 - REAR CASE HALF
2 - HANDLE C-4171
3 - INSTALLER 8128
Fig. 50 Output Shaft Rear Bearing Installation Depth
1 - BEARING (SEATED) AT LOWER EDGE OF CHAMFER
2 - CHAMFER
Fig. 51 Oil Pump Seal Installation
1 - HOUSING SEAL
2 - SPECIAL TOOL 7888
3 - OIL PUMP FEED HOUSING
21 - 558 TRANSFER CASE - NV273DR
TRANSFER CASE - NV273 (Continued)