NV231 Transfer Case
DISASSEMBLYPosition transfer case on shallow drain pan. Remove drain plug and drain lubricant remaining in case.
REAR RETAINER AND OIL PUMP REMOVAL
1. Remove extension housing bolts.
Fig. 10:
2. Tap extension housing with plastic or rawhide mallet to loosen sealer (Fig. 10).
3. Separate extension housing from rear retainer.
Fig. 11:
4. Remove rear bearing snap-ring (Fig. 11).
5. Remove bolts holding rear retainer to rear case half
Fig. 12:
6. Loosen rear retainer with pry tool to break sealer bead. Pry only against retainer boss as shown (Fig. 12).
Fig. 13:
7. Disengage oil pickup tube from oil pump and remove oil pump assembly (Fig. 13).
Fig. 14:
8. Remove pick-up tube O-ring from oil pump (Fig. 14), if necessary. Do not disassemble the oil pump, it is not serviceable.
YOKE AND RANGE LEVER REMOVAL
1. Remove transfer case indicator switch.
2. Remove front yoke nut as follows:
a. Move range lever to 4L position.
Fig. 15:
b. Then remove nut with socket and impact wrench (Fig. 15).
Fig. 16:
3. Remove yoke. If yoke is difficult to remove by hand, remove it with bearing splitter, or with standard two jaw puller (Fig. 16). Be sure puller tool is positioned on yoke and not on slinger as slinger will be damaged.
4. Remove seal washer from front output shaft. Discard washer as it should not be reused.
Fig. 17:
5. Remove nut and washer that attach range lever to sector shaft. Then move sector to neutral position and remove range lever from shaft (Fig. 17).
FRONT OUTPUT SHAFT AND DRIVE CHAIN REMOVAL
1. Support transfer case so rear case is facing upward.
Fig. 18:
2. Remove bolts holding front case to rear case. The case alignment bolts require flat washers (Fig. 18).
Fig. 19:
3. Loosen rear case with flat blade screwdriver to break sealer bead. Insert pry tool blade only into notches provided at each end of case (Fig. 19).
4. Remove rear case from front case.
Fig. 20:
5. Remove oil pickup tube from rear case (Fig. 20).
Fig. 21:
6. Remove mode fork spring (Fig. 21).
Fig. 22:
7. Pull front output shaft upward and out of front output shaft bearing (Fig. 22).
8. Remove front output shaft and chain.
SHIFT FORKS AND MA114 SHAFT REMOVAL
Fig. 23:
1. Remove detent plug, O-ring, detent spring and detent plunger (Fig. 23).
2. Remove mainshaft from mode sleeve and input gear pilot bearing.
Fig. 24:
3. Remove mode fork and sleeve as an assembly (Fig. 24). Note position of sleeve for assembly reference. The short side of the sleeve faces upward.
Fig. 25:
4. Remove range fork and hub as an assembly (Fig. 25). Note fork position for installation reference.
Fig. 26:
5. Remove shift sector from front case (Fig. 26).
Fig. 27:
6. Remove shift sector bushing and O-ring (Fig. 27).
MAINSHAFT DISASSEMBLY
Fig. 28:
1. Remove mode hub retaining ring with heavy duty snap-ring pliers (Fig. 28).
Fig. 29:
2. Slide mode hub off mainshaft (Fig. 29).
Fig. 30:
3. Slide drive sprocket off mainshaft (Fig, 30).
INPUT GEAR AND LOW RANGE GEAR REMOVAL
Fig. 31:
1. Remove front bearing retainer attaching bolts (Fig. 31).
Fig. 32:
2. Remove front bearing retainer. Pry retainer loose with pry tool positioned in slots at each end of retainer (Fig. 32).
3. Remove front bearing retainer seal. Tap seal out with drift and hammer.
Fig. 33:
Fig. 34:
4. Remove input gear retaining ring with heavy duty snap ring pliers (Fig. 33)
INPUT AND LOW RANGE GEAR DISASSEMBLY
Fig. 35:
1. Remove snap-ring that retains input gear in low range gear (Fig. 35).
Fig. 36:
2. Remove retainer (Fig. 36).
Fig. 37:
3. Remove front tabbed thrust washer (Fig. 37).
Fig. 38:
4. Remove input gear (Fig. 38).
Fig. 39:
5. Remove rear tabbed thrust washer from low range gear (Fig. 39).
ASSEMBLY
Lubricate transfer case components with Mopar Dexron II automatic transmission fluid or petroleum jelly (where indicated) during assembly.
BEARING AND SEAL INSTALLATION
CAUTION: The bearing bores in various transfer case components contain oil feed holes. Make sure replacement bearings do not block the holes.
Fig. 40:
1. Remove seal from case with pry tool (Fig. 40).
Fig. 41:
2. Remove bearing retaining ring with screwdriver (Fig. 41).
Fig. 42:
3. Remove bearing with Tool Handle C-4171 and Tool 5065 (Fig. 42).
Fig. 43:
4. Install front output shaft front bearing in case with Tool Handle C-4171 and Installer 5064 (Fig. 43).
Fig. 44:
5. Install output shaft front bearing retaining ring (Fig. 44). Start ring into place by hand. Then use small screwdriver to work ring into case groove. Be sure ring is fully seated before proceeding.
6. Install new front output seal in front case with Installer Tool 8143 as follows:
a. Place new seal on tool. Garter spring on seal goes toward interior of case.
Fig. 45:
b. Start seal in bore with light taps from hammer (Fig. 45). Once seal is started, continue tapping seal into bore until installer tool bottoms against case.
Fig. 46:
7. Remove the output shaft rear bearing with the screw and jaws from Remover L-4454 and Cup 8148 (Fig. 46).
Fig. 47:
Fig. 48:
8. Install new bearing with Tool Handle C-4171 and Installer 5066 (Fig. 47). The bearing bore is chamfered at the top. Install the bearing so it is flush with the lower edge of this chamfer (Fig. 48).
Fig. 49:
9. Using Remover C-4210 and Handle C-4171, drive input shaft bearing from inside the annulus gear opening in the case. (Fig. 49).
10. Install locating ring on new bearing.
11. Position case so forward end is facing upward.
Fig. 50:
12. Using Remover C-4210 and Handle C-4171, drive input shaft bearing into case. The bearing locating ring must be fully seated against case surface (Fig. 50).
Fig. 51:
13. 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. 51).
Fig. 52:
14. Install new pilot bearing with Installer 5065 and Handle C-4171 (Fig. 52).
15. Remove front bearing retainer seal with suitable pry tool.
Fig. 53:
16. Install new front bearing retainer with Installer 7884 (Fig. 53).
17. Remove seal from oil pump housing with a suitable pry tool
Fig. 54:
18. Install new seal in oil pump housing with Installer 7888 (Fig. 54).
19. Remove rear retainer bearing with Installer 8128 and Handle C-4171.
Fig. 55:
20. Install rear bearing in retainer with Handle C-4171 and Installer 5064 (Fig. 55).
INPUT AND LOW RANGE GEAR ASSEMBLY
Fig. 56:
1. Lubricate gears and thrust washers (Fig. 56) with recommended transmission fluid.
2. Install first thrust washer in low range gear (Fig. 56). Be sure washer tabs are properly aligned in gear notches.
3. Install input gear in low range gear. Be sure input gear is fully seated.
4. Install remaining thrust washer in low range gear and on top of input gear. Be sure washer tabs are properly aligned in gear notches.
5. Install retainer on input gear and install snap-ring.
INPUT GEAR AND LOW RANGE GEAR INSTALLATION
Fig. 57:
1. Align and install low range/input gear assembly in front case (Fig. 57). Be sure low range gear pinions are engaged in annulus gear and that input gear shaft is fully seated in front bearing.
Fig. 58:
2. Install snap-ring to hold input/low range gear into front bearing (Fig. 58).
3. Clean gasket sealer residue from retainer and inspect retainer for cracks or other damage.
4. Apply a 3 mm (1/8 inch) bead of Mopar gasket maker or silicone adhesive to sealing surface of retainer.
5. Align cavity in seal retainer with fluid return hole in front of case.
CAUTION: Do not b~lock fluid return cavity on sealing surface of retainer when applying Mopar gasket maker or silicone adhesive sealer. Seal failure and fluid leak can result.
Fig. 59:
6. Install bolts to hold retainer to transfer case (Fig. 59). Tighten to 21 Nm (16 ft. lbs.) of torque.
MAINSHAFT ASSEMBLY
1. Lubricate mainshaft splines with recommended transmission fluid.
2. Slide drive sprocket onto mainshaft.
3. Slide mode hub onto mainshaft.
4. Install mode hub retaining ring. Verify that the retaining ring is fully seated in mainshaft groove.
SHIFT FORKS AND MAINSHAFT INSTALLATION
Fig. 60:
1. Install new sector shaft O-ring and bushing (Fig. 60).
Fig. 61:
2. Install shift sector in case (Fig. 61). Lubricate sector shaft with transmission fluid before installation.
Fig. 62:
3. Install range lever, washer, and nut on sector shaft (Fig. 62). Tighten range lever nut to 27 - 34 Nm (20 - 25 ft. lbs.) torque.
Fig. 63:
4. Assemble and install range fork and hub (Fig. 63). Be sure hub is properly seated in low range gear and engaged to the input gear.
5. Align and insert range fork pin in shift sector/slot.
Fig. 64:
6. Install assembled mainshaft (Fig. 64). Be sure shaft is seated in pilot bearing and input gear.
7. Install new pads on mode fork if necessary.
Fig. 65:
8. Insert mode sleeve in mode fork mode fork. Be sure long side of sleeve is toward long end of shift rail (Fig. 65).
Fig. 66:
9. Install assembled mode fork and sleeve (Fig. 66). Be sure fork rail goes through range fork and into case bore. Also be sure sleeve is aligned and seated on mainshaft hub.
10. Rotate sector to Neutral position.
Fig. 67:
11. Install new O-ring on detent plug (Fig. 67).
12. Lubricate detent plunger with transmission fluid or light coat of petroleum jelly.
13. Install detent plunger, spring and plug (Fig. 67).
14. Verify that plunger is properly engaged in sector.
FRONT OUTPUT SHAFT AND DRIVE CHAIN INSTALLATION
1. Lubricate front output shaft-sprocket assembly, drive chain and drive sprocket with transmission fluid.
Fig. 68:
2. Assemble drive chain and front output shaft (Fig. 68).
3. Start chain on mainshaft drive sprocket.
4. Guide front shaft into bearing and drive sprocket onto mainshaft drive gear (Fig. 68).
Fig. 69:
5. Install mode spring on upper end of mode fork shift rail (Fig. 69).
OIL PUMP AND REAR CASE ASSEMBLY/INSTALLATION
Fig. 70:
1. Install magnet in front case pocket (Fig. 70).
2. Assemble oil pickup screen, connecting hose, and tube.
Fig. 71:
3. Install new pickup tube O-ring in oil pump (Fig. 71).
4. Insert oil pickup tube in oil pump inlet.
Fig. 72:
5. Position assembled oil pump and pickup tube in rear case. Be sure pickup screen is securely seated in case slot. Also be sure oil pump locating tabs are outside rear case (Fig. 72).
6. Apply 3 mm (1/8 inch) wide bead of Mopar gasket maker or silicone adhesive sealer to mounting flange of front case. Work sealer bead around bolt holes.
7. Lift rear case and oil pump and carefully position assembly on front case. Be sure case dowels are aligned and that mode fork rail extends through rear case before seating rear case on front case.
Fig. 73:
8. Install case attaching bolts. Alignment bolts at each end of case are only ones requiring washers (Fig. 73).
9. Tighten case bolts to 27 - 34 Nm (20 - 25 ft. lbs.) torque.
YOKE AND RANGE LEVER INSTALLATION
1. Install indicator switch in front case. Tighten switch to 20 - 34 Nm (15 - 25 ft. lbs.) torque.
Fig. 74:
2. Install range lever, washer and locknut on sector shaft (Fig. 74). Tighten locknut to 27 - 34 Nm (20 - 25 ft. lbs.) torque.
Fig. 76:
3. Install new seal washer on front output shaft (Fig. 76).
4. Lubricate yoke hub with transmission fluid and install yoke on front shaft.
5. Install new seal washer on front shaft.
Fig. 75:
6. Install yoke and new yoke nut on front output shaft (Fig. 75).
7. Tighten yoke nut to 122 - 176 Nm (90 - 130 ft. lbs.) torque. Use Tool C-3281, or similar tool to hold yoke while tightening yoke nut.
REAR RETAINER ASSEMBLY AND INSTALLATION
1. Apply 3 mm (1/8 inch) wide bead of Mopar gasket maker or silicone adhesive sealer to mounting surface of rear retainer. Allow sealer to set-up slightly before proceeding.
2. Install rear retainer on rear case. Tighten retainer bolts to 35 - 46 Nm (26 - 34 ft. lbs).
Fig. 77:
3. Install new output shaft bearing snap-ring (Fig. 77). Lift mainshaft slightly to seat snap-ring in shaft groove, if necessary.
4. Apply 3 mm (1/8 inch) wide bead of Mopar gasket maker or silicone adhesive sealer to mounting surface of extension housing. Allow sealer to set-up slightly before proceeding.
5. Install extension housing on rear retainer.
6. Install extension housing bolts and tighten to 35 - 46 Nm (26 - 34 ft. lbs.).