shaft CHRYSLER CARAVAN 2002 Service Manual

OPERATION
The Transfer Unit provides the power to the rear
wheels through a hypoid ring gear and pinion set.
DIAGNOSIS AND TESTING
SEAL IDENTIFICATION
For accurate seal diagnosis, repair seal name and
location is critical. Refer to (Fig. 1), (Fig. 2), (Fig. 3)
and (Fig. 4) for correct seal name and location.
1 - PLUG 18 - CASE-PTU 35 - SHIM
2 - WASHER FLAT 19 - PINION-PTU 36 - TAPERED ROLLER BEARING
3 - SEAL RING 20 - O-RING 37 - SHAFT ASSY. FRONT L.H.
4 - SNAP RING 21 - SHIM 38 - SEAL RING
5 - BALL BEARING 22 - TAPERED ROLLER BEARING 39 - OIL WIPER
6 - SEAL RING 23 - COVER-PTU CASE REAR 40 - RETAINER DIFFERENTIAL BEARING
7 - COVER-PTU
CASE END24 - FLANGE TUBE-PTU-OUTPUT ASSY. 41 - SHAFT DIFFERENTIAL PINION
8 - TAPERED ROLLER BEARING 25 - LOCK NUT-HEX FLANGE 42 - PIN
9 - SEAL RING 26 - O- RING 43 - CASE DIFFERENTIAL
10 - SEAL RING 27 - RETAINER PLATE 44 - TAPERED ROLLER BEARING CONE
11 - HEX HEAD SCREW 28 - O-RING 45 - SEAL RING
12 - SHAFT-PTU INPUT 29 - BRACKET 46 - SEAL RING
13 - GEAR-PTU RING 30 - THRUST WASHER 47 - PLUG
14 - TROUGH-PTU (RT.) 31 - SIDE GEAR-DIFFERENTIAL 48 - O-RING
15 - TROUGH-PTU (LT.) 32 - FINAL DRIVE GEAR 49 - SHIM
16 - TAPERED ROLLER BEARING 33 - PINION DIFFERENTIAL 50 - MAGNET
17 - HEX HEAD SCREW 34 - WASHER DIFFERENTIAL PINION 51 - DOWEL
52 - SHAFT ASSY. FRONT R.H.
53 - HEX HEAD SCREW
Fig. 1 Seal
1 - INPUT SHAFT
2 - P.T.U. CASE
3 - MAGNET
4 - INPUT SHAFT END SEAL
5 - OUTPUT SHAFT
6 - RING GEAR
7 - REAR COVER
Fig. 2 Seal Location
1 - REAR COVER
2 - END COVER
3 - OUTER HALFSHAFT SEAL
4 - P.T.U. CASE
5 - P.T.U. OUTPUT SEAL
RSPOWER TRANSFER UNIT21-3
POWER TRANSFER UNIT (Continued)
ProCarManuals.com

FLUID LEAK DIAGNOSIS
When diagnosing fluid leaks on the Power Transfer
Unit two weep holes are provided to diagnose certain
seal leaks. These holes are located on the bottom side
of the assembly (Fig. 5).
If fluid leak is detected from either weep hole, seal
replacement is necessary.Do not attempt to repair
the leak by sealing weep holes,they must be kept
clear of sealants for proper seal operation.
If fluid is leaking from weep hole A (Fig. 5) the
type of fluid leaking will determine which seal needs
to be replaced. If the fluid leaking is red in color(transmission fluid) this indicates that the Transmis-
sion differential carrier seal should be replaced. If
the fluid leaking is light brown (gear lube) this indi-
cates that the Power Transfer Unit input seal should
be replaced. For replacement of these seals refer to
Power Transfer Unit Service Procedures.
If fluid is leaking from weep hole B (Fig. 5) the
type of fluid leaking will determine which seal is
leaking. If the fluid leaking is red in color (transmis-
sion fluid) this indicates that the input shaft end seal
should be replaced. If the fluid leaking is light brown
(gear lube) this indicates that the half shaft inner
seal and P.T.U. input shaft cover seal should be
replaced. For replacement of these seals refer to
Power Transfer Unit Service Procedures.
Before condemning any seal or gasket be sure that
the rear rocker arm cover on the engine is not the
cause of the oil leak. Oil leaking from the rocker arm
cover is easily mistaken for a leaking Power Transfer
Unit.
Fig. 3 Seal Location
1 - INPUT SHAFT
2 - OUTPUT SHAFT
3 - REAR COVER
4 - P.T.U. CASE
5 - INPUT SHAFT SEAL
Fig. 4 Seal Location
1 - P.T.U. INPUT SHAFT COVER SEAL
2 - HALF SHAFT INNER SEAL
3 - INSIDE VIEW OF P.T.U. END COVER
Fig. 5 Weep Hole Locations
1 - ENGINE OIL PAN
2 - WEEP HOLE ªAº
3 - TRANSAXLE CASE
4 - P.T.U.
5 - WEEP HOLE ªBº
21 - 4 POWER TRANSFER UNITRS
POWER TRANSFER UNIT (Continued)
ProCarManuals.com

(4) Add 1.15 liters (1.22 quarts) of MopartGear
and Axle Lubricant 80W-90 with suction gun (Fig. 9).
(5) Install inspection plug and torque to 20 N´m
(180 in. lbs.) torque.
(6) Lower vehicle.
REMOVAL
(1) Raise vehicle and remove front wheels.
CAUTION: A certain amount of oil will drain out of
the transaxle when the drive shaft is removed.
(2) Remove right front drive shaft. Install a plug
into the right driveshaft seal hole. (Refer to 3 - DIF-
FERENTIAL & DRIVELINE/HALF SHAFT -
REMOVAL)
(3) Mark propeller shaft front flange.
CAUTION: Do not let propeller shaft to hang freely.
Damage to the shaft will occur.
(4) Remove propeller shaft assembly (Fig. 10).
(Refer to 3 - DIFFERENTIAL & DRIVELINE/PRO-
PELLER SHAFT - REMOVAL)
(5) Remove cradle plate (Fig. 11).
(6) Remove the Power Transfer Unit mounting
bracket bolts at the rear of the unit (Fig. 12).
(7) Remove the right outboard support bracket and
bolts near the right axle shaft.
Fig. 11 Cradle Plate
1 - CRADLE PLATE
Fig. 12 Remove Rear P.T.U Bracket Bolts
1 - P.T.U. MOUNT BRACKET
2 - P.T.U.
Fig. 9 Adding Fluid to PTU
1 - SUCTION GUN
2 - INSPECTION HOLE
Fig. 10 Driveshaft Flange
1 - DRIVESHAFT FLANGE
21 - 6 POWER TRANSFER UNITRS
POWER TRANSFER UNIT (Continued)
ProCarManuals.com

DIFFERENTIAL CARRIER SEAL
REMOVAL
The Power Transfer Unit must be removed from
the vehicle to replace this seal.
(1) Remove P.T.U. from vehicle.
(2) Use a pry bar to remove seal from retainer
plate (Fig. 16). Be careful not to damage seal journal
when removing seal.
INSTALLATION
The Power Transfer Unit must be removed from
the vehicle to replace this seal.
(1) Using a large socket, carefully install new seal.
The spring side of the seal must face the transaxle
differential.
(2) Reinstall the P.T.U. into the vehicle.
(3) Check and fill fluids as required.
END COVER BALL BEARING
REMOVAL
The end cover ball bearing can be removed and
installed without removing the Power Transfer Unit
from the vehicle. When replacing the bearing the output
seal must be removed to gain access to the bearing.
(1) Raise vehicle on hoist.
(2) Remove right front half shaft from vehicle.
(3) Remove output seal with a hammer and chisel
(Fig. 17).
Fig. 17 Output Seal Removal
1 - HAMMER
2 - CHISEL
3 - SEAL
4 - POWER TRANSFER UNIT
MD998334 Seal Installer
MD998346 Bearing Puller
Fig. 16 Transaxle Differential Carrier Seal
1 - TRANSAXLE CASE
2 - DIFFERENTIAL CARRIER SEAL
3 - RETAINER PLATE
RSPOWER TRANSFER UNIT21-9
POWER TRANSFER UNIT (Continued)
ProCarManuals.com

(4) Remove bearing retaining snap ring (Fig. 18).
(5) Use bearing puller MD998346 to remove bear-
ing (Fig. 19).
INSTALLATION
The end cover ball bearing can be removed and
installed without removing the Power Transfer Unit
from the vehicle. When replacing the bearing the output
seal must be removed to gain access to the bearing.
CAUTION: When installing bearing, position the
bearing in place by hand square to the bore. Other-
wise, bearing and/or housing damage may occur
upon installation.(1) Use installer MD998200 and driver handle
C-4171 to install bearing (Fig. 20) into the housing.
(2) Install bearing retaining snap ring.
CAUTION: When installing bearing retaining snap
ring, be sure to index the snap ring so that the
snap ring does not cover bearing oil passage.
(3) Install new outer half shaft seal using
MD998334 seal installer (Fig. 21).Do not reuse the
old seal.
(4) Reinstall right front half shaft.
(5) Check and fill fluids as required.
Fig. 18 Bearing Snap Ring
1 - BEARING
2 - SNAP RING PLIERS
3 - BEARING SNAP RING
Fig. 19 Bearing Removal
1 - P.T.U. END COVER
2 - SPECIAL TOOL MD998346
Fig. 20 Bearing Installation
1 - SPECIAL TOOL MD998200
2 - SPECIAL C-4171
Fig. 21 Installing New Seal
1 - P.T.U. END COVER
2 - HAMMER
3 - SPECIAL TOOL MD998334
21 - 10 POWER TRANSFER UNITRS
END COVER BALL BEARING (Continued)
ProCarManuals.com

END COVER SEAL
REMOVAL
The Power Transfer Unit must be removed from
the vehicle to perform this operation. (Refer to 21 -
TRANSMISSION/TRANSAXLE/POWER TRANSFER
UNIT - REMOVAL)
(1) Remove P.T.U. end cover bolts (Fig. 22).
(2) Gently tap on end cover ears with a hammer to
separate end cover from the case (Fig. 23).
(3) Clean and inspect sealer surfaces.
INSTALLATION
(1) Reinstall cover and tighten bolts to 28 N´m
(250 in. lbs.) in the sequence shown in (Fig. 24).
Retighten first bolt after all others are tight.
CAUTION: When end cover is installed be careful
not to damage the P.T.U. Input Shaft Cover Seal.
(2) Reinstall P.T.U. into vehicle.
(3) Check and fill fluids as required.
Fig. 22 P.T.U. End Cover Bolts
1 - POWER TRANSFER UNIT
2 - FILL PLUG
3 - END COVER
4 - OUTPUT SHAFT
Fig. 23 End Cover Removal
1 - END COVER EARS
2 - HAMMER
3 - POWER TRANSFER UNIT
Fig. 24 Bolt Tightening Sequence
RSPOWER TRANSFER UNIT21-11
ProCarManuals.com

HALF SHAFT INNER SEAL
REMOVAL
The power transfer unit half shaft inner seal is the
smaller of the two seals located on the inside of the
end cover.
(1) Remove power transfer unit from the vehicle.
(2) Remove end cover bolts (Fig. 25).
(3) Tap on end cover ears to separate cover from
case (Fig. 26).
(4) Drive seal out with a hammer and small chisel
(Fig. 27).
Fig. 26 End Cover Removal
1 - END COVER EARS
2 - HAMMER
3 - POWER TRANSFER UNIT
Fig. 27 Seal Removal
1 - END COVER
2 - END COVER SEAL
3 - AXLE SHAFT SEAL
Fig. 25 End Cover Bolts
1 - POWER TRANSFER UNIT
2 - FILL PLUG
3 - END COVER
4 - OUTPUT SHAFT
21 - 12 POWER TRANSFER UNITRS
ProCarManuals.com

INSTALLATION
The power transfer unit half shaft inner seal is the
smaller of the two seals located on the inside of the
end cover.
(1) Clean and inspect seal area.
(2) Install seal with a 1 1/16 inch socket (Fig. 28).
The seal must be installed with the spring side of the
seal facing end cover ball bearing. The seal will bot-
tom against a machined shoulder in the cover.
(3) Clean sealing surfaces of the end cover and
P.T.U. case. Apply a bead of MopartGasket Maker,
Loctite Gasket Eliminator No. 518 or equivalent.
(4) Place end cover onto P.T.U. case and install
bolts. Tighten bolts to 28 N´m (250 in. lbs.) in the
sequence shown in (Fig. 29). Retighten first bolt after
all other bolts are tight.
(5) Reinstall P.T.U. assembly.
(6) Check and fill fluids as required.
INPUT SHAFT COVER SEAL
REMOVAL
The power transfer unit input shaft cover seal is
the larger of the two seals located on the inside of
the end cover. The differential bearing cup must be
removed to service this seal.
(1) Remove P.T.U. end cover bolts (Fig. 30).
Fig. 28 Seal Installation
1 - END COVER
2 - SOCKET
3 - HAMMER
Fig. 29 Bolt Tightening Sequence
Fig. 30 P.T.U. End Cover Bolts
1 - POWER TRANSFER UNIT
2 - FILL PLUG
3 - END COVER
4 - OUTPUT SHAFT
RSPOWER TRANSFER UNIT21-13
HALF SHAFT INNER SEAL (Continued)
ProCarManuals.com

(2) Gently tap on end cover ears to separate cover
from case (Fig. 31).
(3) Use special tool No. 6514 and remove the dif-
ferential bearing race located in the end cover (Fig.
32). The race must be removed to gain access to the
seal.(4) Use special tool No. 7794-A to remove seal (Fig.
33).
INSTALLATION
The power transfer unit input shaft cover seal is
the larger of the two seals located on the inside of
the end cover. The differential bearing cup must be
removed to service this seal.
(1) Clean and inspect seal area.
(2) Use special tool No. MD998803 and install seal
(Fig. 34). When installing seal the spring side of the
seal must face toward the special tool.
Fig. 31 End Cover Removal
1 - END COVER EARS
2 - HAMMER
3 - POWER TRANSFER UNIT
Fig. 32 Bearing Race Removal
1 - END COVER
2 - SPECIAL TOOL
No. 6514
Fig. 33 Seal Removal
1 - END COVER
2 - SPECIAL TOOL 7794±A
3 - SLIDE HAMMER
4 - SOFT JAW VICE
Fig. 34 Seal Installation
1 - SPECIAL TOOL No. MD998803
2 - HAMMER
3 - END COVER
21 - 14 POWER TRANSFER UNITRS
INPUT SHAFT COVER SEAL (Continued)
ProCarManuals.com

(3) Reinstall the original bearing race and shim
using special tool No. 6522 (Fig. 35) and (Fig. 36).CAUTION: The original shim must be installed
behind the bearing cup to maintain proper bearing
preload.
(4) Apply MopartGasket Maker, Loctite Gasket
Eliminator No. 518 or equivalent to sealing surfaces
of end cover.
(5) Place end cover onto P.T.U. case and install
bolts. Tighten bolts to 28 N´m (250 in. lbs.) in the
sequence shown in (Fig. 37). Retighten first bolt after
all others are tight.
CAUTION: When end cover is installed be careful
not to damage the P.T.U. Input Shaft Cover Seal.
(6) Reinstall P.T.U. assembly into vehicle.
(7) Check and fill fluids as required.
Fig. 35 Bearing Shim and Race
1 - SHIM
2 - BEARING RACE
3 - END COVER
Fig. 36 Installing Bearing Race
1 - HAMMER
2 - END COVER
3 - SPECIAL TOOL No. 6522
4 - HANDLE 4171
Fig. 37 Bolt Tightening Sequence
RSPOWER TRANSFER UNIT21-15
INPUT SHAFT COVER SEAL (Continued)
ProCarManuals.com