Disassembly

TRANSFER CASE - NV231

DISASSEMBLY
Position transfer case on shallow drain pan. Remove drain plug and drain lubricant remaining in case.

REAR RETAINER AND OIL PUMP
1. Remove the speedometer adapter.
2. Spread band clamp which holds output shaft boot to the output shaft slinger, or output shaft damper, with a suitable awl, or equivalent.

NOTE: Vehicles built with a 4.0L engine and a manual transmission use a damper weight on the transfer case output shaft. Be sure to identify the transfer case before proceeding.

3. Remove output shaft boot from slinger, or output shaft damper, and output shaft.

Fig. 3 Rear Slinger Removal:

4. If the vehicle is not equipped with an output shaft damper, remove the output shaft rear slinger using Puller MD-998056-A (Fig. 3).
5. If the vehicle is equipped with an output shaft damper, use Screws 8421 and the puller yoke and forcing screw from a bolt-grip puller set, such as those used to remove steering wheels and harmonic balancers, to remove the transfer case output shaft damper.

Fig. 4 Rear Retainer Seal:

6. Use a suitable pry tool, or a slide hammer mounted screw, to remove the seal from the rear retainer (Fig. 4).

Fig. 5 Output Shaft Rear Bearing Retaining Ring:

7. Remove the rear output bearing I.D. retaining ring (Fig. 5).
8. Remove the bolts holding the rear retainer to the rear case half.
9. Tap rear retainer with rawhide or rubber mallet to loosen sealer bead.

Fig. 6 Rear Retainer Removal:

10. Remove rear retainer from rear case half (Fig. 6).
11. Remove snap-ring holding oil pump in position on output shaft.

Fig. 7 Oil Pump Removal:

12. Disengage oil pickup tube from oil pump and remove oil pump assembly. Remove oil pump by tilting the edge of the oil pump from under the edge of the rear case half and sliding the pump (Fig. 7).

Fig. 8 Pick-up Tube O-ring Location:

13. Remove pick-up tube O-ring from oil pump (Fig. 8), if necessary. Do not disassemble the oil pump, it is not serviceable.

YOKE AND RANGE LEVER
1. Remove transfer case indicator switch.
2. Remove front yoke nut as follows:
a. Move range lever to 4L position.

Fig. 9 Yoke Nut Removal:

b. Then remove nut with socket and impact wrench (Fig. 9).

Fig. 10 Yoke Removal:

3. Remove yoke. If yoke is difficult to remove by hand, remove it with bearing splitter, or with standard two jaw puller (Fig. 10). 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. 11 Range Lever Removal:

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. 11).

FRONT OUTPUT SHAFT AND DRIVE CHAIN
1. Support transfer case so rear case is facing upward.

Fig. 12 Rear Case Alignment Bolt Locations:

2. Remove bolts holding front case to rear case. The case alignment bolts require flat washers (Fig. 12).

Fig. 13 Loosening Rear Case - Typical:

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. 13).
4. Remove rear case from front case.

Fig. 14 Oil Pickup Tube Removal:

5. Remove oil pickup tube from rear case (Fig. 14).

Fig. 15 Mode Fork Spring Removal:

6. Remove mode fork spring (Fig. 15).

Fig. 16 Remove Front Output Shaft And Chain:

7. Pull front output shaft upward and out of front output shaft bearing (Fig. 16).
8. Remove front output shaft and chain.

SHIFT FORKS AND MAINSHAFT

Fig. 17 Detent Plug, Spring And Plunger Removal:

1. Remove detent plug, O-ring, detent spring and detent plunger (Fig. 17).
2. Remove mainshaft from mode sleeve and input gear pilot bearing.

Fig. 18 Mode Fork And Sleeve Removal:

3. Remove mode fork and sleeve as an assembly (Fig. 18). Note position of sleeve for assembly reference. The short side of the sleeve faces upward.

Fig. 19 Range Fork And Sleeve Removal:

4. Remove range fork and hub as an assembly (Fig. 19). Note fork position for installation reference.

Fig. 20 Shift Sector Removal:

5. Remove shift sector from front case (Fig. 20).

Fig. 21 Sector Bushing And O-Ring Removal:

6. Remove shift sector bushing and O-ring (Fig. 21).

MAINSHAFT

Fig. 22 Mode Hub Retaining Ring Removal:

1. Remove mode hub retaining ring with heavy duty snap-ring pliers (Fig. 22).

Fig. 23 Mode Hub Removal:

2. Slide mode hub off mainshaft (Fig. 23).

Fig. 24 Drive Sprocket Removal:

3. Slide drive sprocket off mainshaft (Fig. 24).

INPUT GEAR AND LOW RANGE GEAR

Fig. 25 Front Bearing Retainer Bolts:

1. Remove front bearing retainer attaching bolts (Fig. 25).

Fig. 26 Front Bearing Retainer Removal:

2. Remove front bearing retainer. Pry retainer loose with pry tool positioned in slots at each end of retainer (Fig. 26).
3. Remove front bearing retainer seal. Tap seal out with drift and hammer.

Fig. 27 Removing Input Gear Retaining Ring:

4. Remove input gear retaining ring with heavy duty snap-ring pliers (Fig. 27)

Fig. 28 Input Gear And Planetary Carrier Removal:

5. Place front case in horizontal position. Then remove input gear and low range gear as an assembly (Fig. 28). Tap gear out of bearing with plastic mallet if necessary.

INPUT AND LOW RANGE GEAR

Fig. 29 Input Gear Snap-Ring Removal:

1. Remove snap-ring that retains input gear in low range gear (Fig. 29).

Fig. 30 Input Gear Retainer Removal:

2. Remove retainer (Fig. 30).

Fig. 31 Front Tabbed Thrust Washer Removal:

3. Remove front tabbed thrust washer (Fig. 31).

Fig. 32 Input Gear Removal:

4. Remove input gear (Fig. 32).

Fig. 33 Rear Tabbed Thrust Washer Removal:

5. Remove rear tabbed thrust washer from low range gear (Fig. 33).