Dodge RAM 1500 1998 Owner's Manual page 2245

21 - 542 TRANSFER CASE - NV273
TRANSFER CASE - NV273
DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . 542
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . 543
DIAGNOSIS AND TESTING - TRANSFER
CASE - NV273 . . . . . . . . . . . . . . . . . . . . . . . 543
REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . 544
DISASSEMBLY . . . . . . . . . . . . . . . . . . . . . . . . 544
CLEANING . . . . . . . . . . . . . . . . . . . . . . . . . . . 554
INSPECTION . . . . . . . . . . . . . . . . . . . . . . . . . 554
ASSEMBLY . . . . . . . . . . . . . . . . . . . . . . . . . . . 556
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . 568
SPECIFICATIONS
TRANSFER CASE - NV273
SPECIAL TOOLS
TRANSFER CASE NV271/NV273
EXTENSION HOUSING SEAL AND DUST BOOT
REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . 571
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . 571
TRANSFER CASE - NV273
DESCRIPTION
The NV273 is an electronically controlled part-time
transfer case with a low range gear reduction system.
The NV273 has three operating ranges plus a NEU-
TRAL position. The low range system provides a gear
reduction ratio for increased low speed torque capa-
bility.
The geartrain is mounted in two aluminum case
halves attached with bolts. The mainshaft front and
rear bearings are mounted in aluminum case halves.
OPERATING RANGES
Transfer case operating ranges are:
• 2WD (2-wheel drive)
• 4HI (4-wheel drive)
• 4LO (4-wheel drive low range)
• NEUTRAL
The 2WD range is for use on any road surface at
any time.
TRANSFER CASE - NV273
TABLE OF CONTENTS
page
. . . . . . . . . . . . . 568
. . . . . . . . . 569
FLUID
STANDARD PROCEDURE - FLUID DRAIN AND
REFILL . . . . . . . . . . . . . . . . . . . . . . . . . . . . 571
FRONT OUTPUT SHAFT SEAL
REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . 572
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . 572
MODE SENSOR
DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . 573
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . 573
SELECTOR SWITCH
DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . 574
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . 574
SHIFT MOTOR
DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . 575
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . 575
REMOVAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . 575
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . 575
The 4HI 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 wet or slip-
pery or 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.
SHIFT MECHANISM
Operating ranges
mounted shift selector switch. The shift selector
switch provides a input to the Transfer Case Control
Module (TCCM) to indicate the driver's desire to
change operating ranges. The TCCM uses this input,
along with input from the transfer case mounted
mode sensor and information from the vehicle's bus,
to determine if a shift is permitted. If the TCCM
decides the shift is permitted, the TCCM controls the
shift motor, mounted to the exterior of the transfer
case, to perform the shift.
are selected with
DR
page
a dash