(2) Install housing seal with Handle C-4171 (Fig.
133) and Installer.
²Light Duty - Installer C-3972-A
²Heavy Duty - Installer 8154
(3) Install propeller shaft with reference marks
aligned.
(4) Check and fill transmission.
SHIFT MECHANISM
REMOVAL
(1) Remove transmission from vehicle.
(2) Remove shift mechanism cover bolts.
(3) Pry up shift mechanism cover at slots provided
in cover (Fig. 134).
(4) Raise cover enough to disengage it from align-
ment dowels in gear case (Fig. 135).
(5) Raise front of shift mechanism cover and lift
cover up and off gear case (Fig. 135).
FIFTH-REVERSE SHIFT FORK PADS
Three shift pads on the forks are held in place by
tension and a small locating tang (Fig. 136).
To remove the pads, grasp a pad with hand and tilt
it out and off the fork. If pad is difficult to remove by
hand, insert a screwdriver blade between the pad
and fork and pry the pad off.
EXPANSION PLUG
The expansion plugs at the rear of the shift rail
bores (Fig. 137) can be replaced if loose/leaking.
(1) Drill 6 mm (1/4 in.) diameter hole in center of
the plug to be removed.
(2) Pry plug out of cover with tapered punch.
Fig. 133 Pinion Seal
1 - HANDLE
2 - INSTALLER
Fig. 134 LOOSEN SHIFT MECHANISM
1 - SHIFT MECHANISM COVER SLOT
2-PRYTOOL
Fig. 135 SHIFT MECHANISM COVER
1 - SHIFT MECHANISM COVER
2 - ALIGNMENT DOWELS
Fig. 136 SHIFT FORK PAD LOCATIONS
1 - SHIFT FORK PADS
2 - FIFTH-REVERSE FORK
21 - 86 MANUAL TRANSMISSION - NV4500DR
EXTENSION HOUSING SEAL (Continued)
(3) Clean all chips from shift cover and plug bores.
Then clean plug bores with solvent and dry with
clean shop towel.
INSTALLATION
EXPANSION PLUG
(1) Apply small bead of Mopar silicone sealer or
equivalent to outer edge of each new plug.
(2) Position each plug in bore and tap into place
with hammer and punch or socket.
FIFTH-REVERSE SHIFT FORK PADS
(1) Align pad locating tab.
(2) Snap pads into place and verify locating tabs
are locked-in.
SHIFT COVER
(1) Clean mating surfaces of shift mechanism
cover and gear case with wax and grease remover.
(2)
Apply a small amount of Mopar silicone sealer or
equivalent to sealing surface of shift mechanism cover.
CAUTION: Do not use an excessive amount sealer.
Excess can squeezed into gear case and could
block lubricant feed holes in time.
(3) Lubricate synchro sleeves with CastroltSyn-
torq gear lubricant or equivalent. Then apply light
coat of petroleum jelly to shift fork contact surfaces.
(4) Verify shift fork pads (Fig. 138) are secure.
(5) Verify 1-2 and 3-4 synchro sleeves and forks in
shift cover are in neutral position.
(6) Align and seat shift mechanism cover on trans-
mission.
NOTE: If cover will not seat, it may not be aligned
on gear case dowels or shift forks are not aligned
with sleeves and shift lug.
(7) Apply Mopar Lock N' Seal or equivalent to
threads of shift cover bolts.
(8) Install shift cover mechanism bolts and tighten
to 27-31 N´m (216-276 in. lbs.).(9)
Apply sealer to backup lamp switch. Install switch
into cover and tighten to 22-34 N´m (193-265 in. lbs.).
(10) Install vent assembly if removed. Apply an
adhesive/sealer to vent tube to help secure it in cover.
(11) Install transmission.
SHIFT COVER
REMOVAL
(1) Shift transmission into Neutral.
(2) Unscrew and remove the shift lever extension
from the shift
(3) Remove screws attaching shift boot to floorpan.
Then slide boot upward on the shift lever.
(4) Remove the bolts holding the shift tower to the
isolator plate and transmission shift cover.
(5) Remove the shift tower and isolator plate from
the transmission shift cover.
INSTALLATION
(1) Clean the mating surfaces of shift tower, isola-
tor plate and shift cover with suitable wax and
grease remover.
(2) Apply Mopar Gasket Maker or equivalent to
the sealing surface of the shift cover. Do not over
apply sealant.
(3) Install the isolator plate onto the shift cover,
metal side down.
(4) Install the shift tower onto the isolator plate.
No sealant is necessary between the shift tower and
the isolator plate.
(5) Verify shift tower, isolator plate and shift tower
bushings are properly aligned.
(6) Install bolts to hold the shift tower to the iso-
lator plate and the shift cover. Tighten the shift
tower bolts to 10.2-11.25 N´m (7.5-8.3 ft. lbs.).
(7) I
nstall shift lever extension, shift boot and bezel.
Fig. 137 EXPANSION PLUG LOCATION
1 - EXPANSION PLUGS
Fig. 138 SHIFT FORK PAD
1 - SHIFT FORK PADS
2 - FIFTH-REVERSE FORK
DRMANUAL TRANSMISSION - NV4500 21 - 87
SHIFT MECHANISM (Continued)
MANUAL TRANSMISSION - NV5600
TABLE OF CONTENTS
page page
MANUAL TRANSMISSION - NV5600
DESCRIPTION.........................88
OPERATION...........................90
DIAGNOSIS AND TESTING................90
REMOVAL.............................90
DISASSEMBLY.........................91
CLEANING - TRANSMISSION.............106
INSPECTION.........................106
ASSEMBLY...........................106
INSTALLATION........................121
SPECIFICATIONS - NV5600..............123SPECIAL TOOLS.......................123
ADAPTER HOUSING SEAL
REMOVAL............................128
INSTALLATION........................128
EXTENSION HOUSING SEAL
REMOVAL............................128
INSTALLATION........................128
SHIFT COVER
REMOVAL............................129
INSTALLATION........................129
MANUAL TRANSMISSION -
NV5600
DESCRIPTION
The NV5600 is a six speed constant mesh manual
transmission (Fig. 1). All gear ranges including
reverse are synchronized. First and second gears uti-
lize dual cone synchronizers in order to aid shifting.
Sixth gear is an overdrive range. The transmission
uses cast iron for the gear case and extension/
adapter housing and aluminum for the clutch hous-
ing.To drain the trans remove the bottom PTO cover
bolt. Fill the trans through the plug to the rear of the
PTO cover (Fig. 1). Dry fill is approximately 4.5 liters
(9.5 pints) or to the bottom edge of the fill plug hole.
The gear ratios are:GEAR RATIOS
GEAR RATIO
FIRST 5.63:1
SECOND 3.38:1
THIRD 2.04:1
FOURTH 1.39:1
FIFTH 1.00:1
SIXTH 0.73:1
REVERSE 5.63:1
21 - 88 MANUAL TRANSMISSION - NV5600DR
IDENTIFICATION
The transmission has two identification tags
attached to the driver side upper clutch housing (Fig.
2). One tag provides the transmission part number.
The second tag provides sequencing and build date
information. The information on the tags are essen-
tial to correct parts ordering.
OPERATION
The driver selects a particular gear by moving the
shift lever to the desired gear position. As the shift
lever moves the selected shift rail, the shift fork
attached to that rail begins to move. The fork is posi-
tioned in a groove in the outer circumference of the
synchronizer sleeve. As the shift fork moves the syn-
chronizer sleeve, the synchronizer begins to speed-up
or slow down the selected gear (depending on
whether we are up-shifting or down-shifting). The
synchronizer does this by having the synchronizer
hub splined to the mainshaft or the countershaft in
some cases, and moving the blocker ring into contact
with the gear's friction cone. As the blocker ring and
friction cone come together, the gear speed is brought
up or down to the speed of the synchronizer. As the
two speeds match, the splines on the inside of the
synchronizer sleeve become aligned with the teeth on
the blocker ring and friction cone and eventually will
slide over the teeth, locking the gear to the main-
shaft or countershaft through the synchronizer.
DIAGNOSIS AND TESTING
LOW LUBRICANT LEVEL
A low transmission lubricant level is generally the
result of a leak, inadequate lubricant fill or an incor-
rect lubricant level check. A correct lubricant level
check can only be made when the vehicle is level.
Also allow the lubricant to settle for a minute or sobefore checking. These recommendations will ensure
an accurate check and avoid an underfill or overfill
condition. Always check the lubricant level after any
addition of fluid to avoid an incorrect lubricant level
condition.
Leaks can occur at the mating surfaces of the gear
case, adaptor or extension housing, or from the front/
rear seals. A suspected leak could also be the result
of an overfill condition. Leaks at the rear of the
extension or adapter housing will be from the hous-
ing oil seals. Leaks at component mating surfaces
will probably be the result of inadequate sealer, gaps
in the sealer, incorrect bolt tightening or use of a
non-recommended sealer. A leak at the front of the
transmission will be from either the front bearing
retainer or retainer seal. Lubricant may be seen drip-
ping from the clutch housing after extended opera-
tion. If the leak is severe, it may also contaminate
the clutch disc causing the disc to slip, grab and or
chatter.
HARD SHIFTING
Hard shifting is usually caused by a low lubricant
level, improper or contaminated lubricants. The con-
sequence of using non-recommended lubricants is
noise, excessive wear, internal bind and hard shift-
ing. Substantial lubricant leaks can result in gear,
shift rail, synchro, and bearing damage. If a leak
goes undetected for an extended period, the first indi-
cations of component damage are usually hard shift-
ing and noise.
Component damage, incorrect clutch adjustment or
damaged clutch pressure plate or disc are additional
probable causes of increased shift effort. Incorrect
adjustment or a worn/damaged pressure plate or disc
can cause incorrect release. If clutch problem is
advanced, gear clash during shifts can result. Worn
or damaged synchro rings can cause gear clash when
shifting into any forward gear. In some new or
rebuilt transmissions, new synchro rings may tend to
stick slightly causing hard or noisy shifts. In most
cases this condition will decline as the rings wear-in.
TRANSMISSION NOISE
Most manual transmissions make some noise dur-
ing normal operation. Rotating gears generate a mild
whine that is audible, but generally only at extreme
speeds. Severe highly audible transmission noise is
generally the initial indicator of a lubricant problem.
Insufficient, improper or contaminated lubricant
will promote rapid wear of gears, synchros, shift
rails, forks and bearings. The overheating caused by
a lubricant problem, can also lead to gear breakage.
REMOVAL
(1) Shift transmission into Neutral.
Fig. 2 IDENTIFICATION TAG LOCATION
1 - IDENTIFICATION TAGS
21 - 90 MANUAL TRANSMISSION - NV5600DR
MANUAL TRANSMISSION - NV5600 (Continued)
(6) Remove primary shift rail detent plunger (Fig.
9).
(7) Remove clutch housing bolts (10) (Fig. 10) from
inside the housing.(8) Remove shift rail blocker bolt (Fig. 11) from the
side of the transmission gear case.
EXTENSION/ADAPTER HOUSING
(1) Remove bolts holding the extension/adapter
housing onto the transmission gear case.
(2) Remove extension/adapter housing from the
transmission gear case with Puller 8244 (Fig. 12).
NOTE: It may be necessary to straighten the housing
during removal due to the tendency for the reverse
idler shaft to bind into one side of the housing.
Fig. 9 PRIMARY SHIFT RAIL DETENT PLUNGER
1 - DETENT PLUNGER
Fig. 10 CLUTCH HOUSING BOLTS
1 - BOLTS (10)
Fig. 11 SHIFT RAIL BLOCKER BOLT
1 - BLOCKER BOLT
Fig. 12 TRANSMISSION CASE PULLER
1 - PULLER
2 - EXTENSION/ADAPTER HOUSING
DRMANUAL TRANSMISSION - NV5600 21 - 93
MANUAL TRANSMISSION - NV5600 (Continued)
(2) Attach Fixture 8232 to the output shaft and
countershaft (Fig. 27).
(3) Attach an engine crane or equivalent to Fixture
8232 and raise the geartrain approximately 1/4 in.
from the clutch housing.
(4) Remove 5-6 crossover bracket from the clutch
housing.
(5) Lower the geartrain back into the clutch hous-
ing.
(6) Install Holding Tool 8242 (Fig. 28) onto the 5-6
synchro and tighten the screw to hold the 5-6 syn-
chro together during the removal operation.
NOTE: Note the order of the shift fork arms at the
primary shift rail, while in the Neutral position.
(7) Raise geartrain and shift rails until all the
shift rails clear the clutch housing.
(8) Remove shift rails from the rest of the
geartrain (Fig. 29).
(9) Raise the geartrain until the input shaft is
clear of the clutch housing.
Fig. 27 FIXTURE/OUTPUT SHAFT
1 - OUTPUT SHAFT
2 - FIXTURE
Fig. 28 Remove Holding Tool
1 - HOLDING TOOL
2 - 5-6 SYNCHRO
Fig. 29 SHIFT RAILS
1 - 5-6 SHIFT RAIL
21 - 98 MANUAL TRANSMISSION - NV5600DR
MANUAL TRANSMISSION - NV5600 (Continued)
(3) Remove output shaft pocket bearing race from
the input shaft with Puller L-4518 (Fig. 36).
(4) Remove input shaft bearing and oil guide from
the input shaft with Collar 6444-8, Jaws 8243, Puller
Rods 6444-6 and the remainder of Puller 6444 (Fig.
37).
OUTPUT SHAFT
NOTE: Some gear and synchro components can be
installed backwards. Mark the gears, clutch gears,
synchro hubs, and sleeves for installation reference
during disassembly. Use paint or a scribe for mark-
ing purposes. Then stack the geartrain parts in
order of removal.
(1) Remove first gear from the output shaft.
(2) Remove first gear bearing from the output
shaft (Fig. 38).
Fig. 36 OUTPUT SHAFT POCKET BEARING RACE
1 - PULLER
2 - INPUT SHAFT
Fig. 37 INPUT SHAFT BEARING
1 - PULLER
2-JAWS
Fig. 38 FIRST GEAR BEARING
1 - OUTPUT SHAFT
2 - FIRST GEAR BEARING
DRMANUAL TRANSMISSION - NV5600 21 - 101
MANUAL TRANSMISSION - NV5600 (Continued)
ADAPTER HOUSING SEAL
REMOVAL
(1) Raise and support vehicle.
(2) Mark propeller shaft and yokes for installation
reference and remove shaft.
(3) Remove the transfer case.
(4) Remove the adapter housing seal with a pry
tool or slide hammer with a screw.
INSTALLATION
(1) Install adapter housing seal with Installer and
Handle C-4171.
(2) Install transfer case.
(3) Install propeller shaft with reference marks
aligned.
(4) Check fluid level.
(5) Remove support and lower vehicle.
EXTENSION HOUSING SEAL
REMOVAL
(1) Mark propeller shaft and pinion yoke for
installation reference and remove the propeller shaft.
(2) Remove extension housing seal with a pry tool
or a slide hammer and screw.
(3) Remove extension housing bushing with
Remover 8155 (Fig. 97).
INSTALLATION
(1) Install extension housing bushing with
Installer 8156 and Handle C-4171 (Fig. 98).
(2) Install extension housing seal with Installer
8154 and Handle C-4171 (Fig. 99).
(3) Install propeller shaft with reference marks
aligned.
(4) Check and fill transmission.
Fig. 97 EXTENSION HOUSING BUSHING REMOVAL
1 - REMOVER
Fig. 98 Install Extension Housing Bushing
1 - HANDLE
2 - INSTALLER
3 - BUSHING
Fig. 99 EXTENSION HOUSING SEAL INSTALLER
1 - INSTALLER
2 - HANDLE
21 - 128 MANUAL TRANSMISSION - NV5600DR