2002 DODGE RAM lock

GEAR RATIOS
GEAR RATIO
FIRST 5.61:1
SECOND 3.04:1
THIRD 1.67:1
FOURTH 1.00:1
FIFTH 0.75:1
REVERSE 5.04:1
IDENTIFICATION
The transmission identification tag is attached to
the driver side PTO cover (Fig. 3).
The tag provides the transmission model number,
build date and part number. Be sure to reinstall the
I.D. tag if removed during service. The information
on the tag is essential to correct parts ordering.
OPERATION
The manual transmission receives power through
the clutch assembly from the engine. The clutch disc
is splined to the transmission input shaft and is
turned at engine speed at all times that the clutch is
engaged. The input shaft is connected to the trans-
mission countershaft through the mesh of fourth
speed gear on the input shaft and the fourth counter-
shaft gear. At this point all the transmission gears
are spinning.The driver selects a particular gear by moving the
shift lever to the desired gear position. This move-
ment moves the internal transmission shift compo-
nents to begin the shift sequence. As the shift lever
moves the selected shift rail, the shift fork attached
to that rail begins to move. The fork is positioned in
a groove in the outer circumference of the synchro-
nizer sleeve. As the shift fork moves the synchronizer
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 the friction cone and eventually will slide
over the teeth, locking the gear to the mainshaft, 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 so
before 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.
Fig. 3 Identification Tag Location
1 - PTO COVER
2 - I.D. TAG
BR/BEMANUAL - NV4500 21 - 3
MANUAL - NV4500 (Continued)

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) Disconnect battery negative cable.
(2) Shift transmission into Neutral.
(3) Remove shift boot screws from floorpan and
slide boot upward on the shift lever.
(4) Remove shift lever extension from shift tower
and lever assembly.
(5) Remove shift tower bolts holding tower to iso-
lator plate and transmission shift cover.
(6) Remove shift tower and isolator plate from
transmission shift cover.
(7) Raise and support vehicle.
(8) Remove skid plate, if equipped.
(9) Mark propeller shaft and axle yokes for instal-
lation reference and remove shaft/shafts.
(10) Remove exhaust system Y-pipe.
(11) Disconnect speed sensor and backup light
switch connectors.
(12) Support engine with safety stand and a wood
block.
(13) If transmission is to be disassembled for,
remove drain bolt at bottom of PTO cover and drain
lubricant (Fig. 4).
TWO WHEEL DRIVE
(1) Remove nuts/bolts attaching transmission to
rear mount.
(2) Support and secure transmission with safety
chains to a transmission jack.
(3) Remove rear crossmember.
(4) Remove clutch slave cylinder bolts and move
cylinder aside for clearance.
(5) Remove transmission harness wires from clips
on transmission shift cover.
(6) Remove transmission to clutch housing bolts.
(7) Slide transmission and jack rearward until
input shaft clears clutch housing.
(8) Lower transmission jack and remove transmis-
sion from under vehicle.
FOUR WHEEL DRIVE
(1) Disconnect transfer case shift linkage at trans-
fer case range lever. Then remove transfer case shift
mechanism from transmission (Fig. 5).
(2) Support and secure transfer case to transmis-
sion jack with safety chains.
(3) Remove transfer case mounting nuts.
(4) Move transfer case rearward until input gear
clears transmission mainshaft.
(5) Lower transfer case assembly and move it from
under vehicle.
(6) Support and secure transmission with safety
chains to a transmission jack.
(7) Remove transmission harness from retaining
clips on transmission shift cover.
(8) Remove bolts/nuts attaching transmission
mount to rear crossmember.
(9) Remove rear crossmember.
(10) Remove clutch slave cylinder splash shield, if
equipped.
Fig. 4 Drain Bolt
1 - PTO COVER
2 - DRAIN BOLT
3 - FILL PLUG
21 - 4 MANUAL - NV4500BR/BE
MANUAL - NV4500 (Continued)

MAINSHAFT AND GEARTRAIN
(1) Move 1-2 and 3-4 synchro sleeves into neutral.
(2) Remove drive gear thrust bearing from forward
end of mainshaft (Fig. 27).
(3) Remove fourth gear clutch gear and synchro
stop ring from mainshaft (Fig. 28).
(4) Roll gear case onto left side (Fig. 29).
(5) To remove mainshaft assembly (Fig. 29) lift
front end of mainshaft slightly.
NOTE: Handling mainshaft carfully because gears
are lose on the mainshaft.(6) Grasp mainshaft rear splines, then turn spline
end of mainshaft counterclockwise to rotate shaft and
geartrain out of case. Tilt mainshaft outward and
removed from case.
REVERSE IDLER AND COUNTERSHAFT
(1) Remove countershaft rear bearing plate (Fig.
30).
Fig. 27 Drive Gear Thrust Bearing
1 - MAINSHAFT
2 - DRIVE GEAR THRUST BEARING
Fig. 28 Fourth Gear Clutch Gear Stop Ring
1 - FOURTH GEAR SYNCHRO STOP RING
2 - FOURTH SPEED CLUTCH GEAR
Fig. 29 Mainshaft And Geartrain
1 - MAINSHAFT AND CASE
Fig. 30 Countershaft Rear Bearing Plate
1 - REAR BEARING PLATE
2 - COUNTERSHAFT
BR/BEMANUAL - NV4500 21 - 11
MANUAL - NV4500 (Continued)

CLEANING
Clean the gears, shafts, shift components and trans-
mission housings with a standard parts cleaning sol-
vent. Do not use acid or corrosive base solvents. Dry
all parts except bearings with compressed air.
Clean the shaft bearings with a mild solvent such
as Mopar degreasing solvent, Gunk or similar sol-
vents. Do not dry the bearings with compressed air.
Allow the bearings to either air dry or wipe them dry
with clean shop towels.
INSPECTION
NOTE: Minor corrosion, nicks, or pitting can be
smoothed with 400 grit emery and polished out with
crocus cloth.
Inspect the reverse idler gear, bearings, shaft and
thrust washers. Replace the bearings if the rollers
are worn, chipped, cracked, flat-spotted or brinnelled.
Replace the gear if the teeth are chipped, cracked or
worn thin.
Inspect the front bearing retainer and bearing cup.
Replace the bearing cup if scored, cracked, brinnelled
or rough. Check the release bearing slide surface of
the retainer carefully. Replace the retainer if worn or
damaged in any way.
Inspect mainshaft bearing surfaces, splines, snap
ring grooves and threads. Replace the shaft if any
surfaces exhibit considerable wear or damage.
Inspect the countershaft and bearings. Replace the
shaft if any surfaces exhibit considerable wear or
damage.
Inspect shift forks for wear and distortion. Check
fit of the sleeve in the fork to be sure the two parts
fit and work smoothly. Replace the fork if the roll pin
holes are worn oversize or damaged. Do not attempt
to salvage a worn fork. Replace shift fork roll pins if
necessary or if doubt exists about their condition.
The all bearings for wear, roughness, flat spots,
pitting or other damage. Replace the bearings if nec-
essary.
Inspect the blocker rings and fiction cones. replace
either part if worn or damaged in any way. Replace if
the friction material is burned, flaking off or worn.
Inspect synchro components wear or damage.
Replace parts if worn, cracked or distorted.
Inspect all of the thrust washers and locating pins.
Replace the pins if bent or worn. Replace the wash-
ers if worn or the locating pin notches are distorted.
Inspect the case and housing/adapter sealing and
mating surfaces are free of burrs and nicks. Inspcet
the alignment dowels in the case top surface and in
the housing/adapter are tight and in good condition.
Replace the gear case or housing/adapter if cracked
or broken.
Fig. 61 Reverse Clutch Gear
1 - REVERSE CLUTCH GEAR
Fig. 62 First Gear
1 - FIRST GEAR
Fig. 63 First Gear Bearing
1 - MAINSHAFT
2 - FIRST GEAR BEARING
21 - 20 MANUAL - NV4500BR/BE
MANUAL - NV4500 (Continued)

(12) Lift countershaft upward and position wood
block between front of shaft and case (Fig. 69).
(13) Install rear bearing cone on countershaft with
Installer C-4040 (Fig. 70).
(14) Remove wood block from under countershaft
and lower countershaft front bearing into front bear-
ing cup.
(15) Lubricate countershaft rear bearing cup and
cone with petroleum jelly.
(16) Install countershaft rear bearing cup in gear
case and over rear bearing (Fig. 71). Tap cup into
place with plastic mallet if necessary.
(17) Install countershaft rear bearing plate (Fig.
72).NOTE: Verify plate is seated in notch in reverse
idler shaft before tightening bearing plate bolts.
(18) Apply Mopar silicone adhesive/sealer or equiv-
alent to flange and lip of new cap. Installnewfront
bearing cap in gear case (Fig. 73) with Handle
C-4171 and Installer C-3972-A.
Fig. 67 Idler Gear
1 - REAR THRUST WASHER
2 - REVERSE IDLER GEAR
3 - FRONT THRUST WASHER
Fig. 68 Reverse Idler Shaft
1 - COUNTERSHAFT
2 - SHAFT NOTCH
3 - REVERSE IDLER SHAFT
Fig. 69 Supporting Countershaft With Wood Block
1 - COUNTERSHAFT
2 - WOOD BLOCK
Fig. 70 Countershaft Rear Bearing
1 - INSTALLER C-4040
2 - REAR BEARING
3 - COUNTERSHAFT
21 - 22 MANUAL - NV4500BR/BE
MANUAL - NV4500 (Continued)

COUNTERSHAFT END PLAY
(1) Rotate countershaft 4-5 times to seat bearings.
(2) Mount dial indicator on case. Then position
indicator plunger on end of countershaft and zero
dial indicator (Fig. 74).
(3) Raise countershaft with screwdriver and note
end play reading on dial indicator. End play should
be 0.051 - 0.15 mm (0.002 - 0.006 in.).
(4) Remove countershaft rear bearing plate.
(5) Install a end play shim that will provide mini-
mum countershaft end play. Position shim on rear
bearing cup (Fig. 75).
Fig. 71 Countershaft Rear Bearing Cup
1 - COUNTERSHAFT REAR BEARING CUP
Fig. 72 Countershaft Rear Bearing Plate
1 - COUNTERSHAFT
2 - REAR BEARING PLATE
3 - IDLER SHAFT
Fig. 73 Countershaft Front Bearing Cap
1 - FRONT BEARING CAP (SEAT WITH WOOD BLOCK)
Fig. 74 Measuring Countershaft End Play
1 - DIAL INDICATOR
2 - COUNTER SHAFT
3 - INDICATOR MOUNTING ARM AND BASE
Fig. 75 Countershaft End Play Shim
1 - REAR BEARING CUP
2 - END PLAY SHIM (SELECTIVE)
BR/BEMANUAL - NV4500 21 - 23
MANUAL - NV4500 (Continued)

(5) If 1-2 synchro hub and sleeve were disassem-
bled for service, reassemble hub, sleeve, struts and
springs as follows:
(a) Align and install sleeve on hub. Rotate sleeve
until it slides onto hub. Sleeve only fits one way
and will easily slide onto hub when long slot in
sleeve, aligns with long shoulder on hub (Fig. 80).
(b) Place wood blocks under hub that will raise
hub about 3.5 cm (1.375 in.) above surface of work-
bench. Then allow sleeve to drop down on hub (Fig.
81).
(c) Install springs and struts in hub (Fig. 81).
Use lots of petroleum jelly to hold them in place.
Then compress struts with your fingers and move
sleeve upward until struts are started in sleeve.
Verify that struts are engaged in sleeve before pro-
ceeding.
(d) Turn synchro assembly upright. Then move
sleeve into neutral position on hub and work struts
into sleeve at same time. Be sure struts are seated
and springs are not displaced during assembly.
(6) Install first gear stop ring in 1-2 synchro hub
and sleeve (Fig. 82). Verify stop ring is seated and
engaged in hub and sleeve.
Fig. 79 First Gear Clutch Cone Snap Ring
1 - FIRST GEAR CLUTCH CONE
2 - MAINSHAFT 1-2 SYNCHRO HUB
3 - CLUTCH CONE SNAP RING
Fig. 80 1-2 Synchro Sleeve On Hub
1 - ALIGN WIDE SLOT IN SLEEVE WITH WIDE SPLINE OF HUB
2 - 1-2 SLEEVE AND HUB
Fig. 81 1-2 Synchro Struts And Springs
1 - WOOD BLOCKS
2 - HUB
3 - SLEEVE
4 - STRUTS AND SPRINGS (4 EACH)
Fig. 82 First Gear Stop Ring In Synchro Hub
BR/BEMANUAL - NV4500 21 - 25
MANUAL - NV4500 (Continued)

DRIVE GEAR AND RETAINER
(1) Install bearing on drive gear with Installer
6448 (Fig. 109).
(2) Lubricate pilot bearing with petroleum jelly
and install it in drive gear bore.
(3) Install drive gear on mainshaft. Work gear
rearward until mainshaft hub is seated in pilot bear-
ing.
(4) Install bearing cup in front retainer with Han-
dle C-4171 and Installer C-4308 (Fig. 110).
(5) Install new oil seal in front bearing retainer
with Installer 6052 (Fig. 111). Use one or two wood
blocks to support retainer as shown. Lubricate seal
lip with petroleum jelly after installation.
(6) Clean contact surfaces of gear case and front
bearing retainer with a wax and grease remover.
(7) Apply Mopar Silicone Sealer or equivalent to
flange surface of front bearing retainer (Fig. 112).(8) Install front bearing retainer over drive gear
and start it into case.
(9) Start front bearing retainer in gear case. Verify
retainer lube channel is at the top-center(12
O'clock)position (Fig. 112).
(10) Align front bearing retainer bolt holes and tap
retainer into place with plastic mallet. Installnew
retainer bolts and tighten to 30 N´m (22 ft. lbs.) (Fig.
113).
NOTE: Never reuse the old bolts.
Fig. 108 Drive Gear Thrust Bearing
1 - MAINSHAFT
2 - DRIVE GEAR THRUST BEARING
Fig. 109 Front Bearing On Drive Gear
1 - INSTALLER 6448
2 - BEARING
3 - DRIVE GEAR
Fig. 110 Front Bearing Cup In Retainer
1 - INSTALLER C-4308
2 - HANDLE C-4171
3 - WOOD BLOCKS
4 - RETAINER
Fig. 111 Bearing Retainer Oil Seal
1 - INSTALLER 6052
2 - RETAINER
3 - WOOD BLOCK
21 - 32 MANUAL - NV4500BR/BE
MANUAL - NV4500 (Continued)