Transfer Case - NV233 Transfer Case: Other Dodge Dakota III

OPERATING RANGES

Transfer case operating ranges are

1. 2WD (2-wheel drive)
2. 4HI (4-wheel drive)
3. 4LO (4-wheel drive low range)
4. NEUTRAL

The 2WD range is for use on any road surface at any time.

The 4HI and 4LO ranges are for off road use only. They are not for use on hard surface roads. The only exception being when the road surface is wet or slippery or covered by ice and snow.

The low range reduction gear system is operative in 4LO range only. This range is for extra pulling power in off road situations. Low range reduction ratio is 2.72:1.

SHIFT MECHANISM

Operating ranges are selected with a dash mounted shift selector switch. The shift selector switch provides a input to the Front Control Module (FCM) to indicate the driver's desire to change operating ranges. The FCM uses this input, along with input from the transfer case mounted mode sensor and information from the vehicle's bus, to determine if a shift is permitted. If the FCM decides the shift is permitted, the FCM controls the shift motor, mounted to the exterior of the transfer case, to perform the shift.

Scheme 73

A circular ID tag (1) is attached to the rear case of each transfer case. The ID tag provides the transfer case model number, assembly number, serial number, and low range ratio. (Scheme 73)

The transfer case serial number also represents the date of build.

CLEANING

Clean the transfer case parts with a standard parts cleaning solvent. Remove all traces of sealer from the cases and retainers with a scraper and 3M™ all purpose cleaner. Use compressed air to remove solvent residue from oil feed passages in the case halves, retainers, gears, and shafts.

The oil pickup screen can be cleaned with solvent. Shake excess solvent from the screen after cleaning and allow it to air dry. Do not use compressed air.

Scheme 74

Inspect the splines on the hub (1), shaft (3), and the teeth on the sprocket (2). (Scheme 74) Minor nicks and scratches can be smoothed with an oilstone. However, replace any part that is damaged.

Check the contact surfaces in the sprocket bore and on the mainshaft. Minor nicks and scratches can be smoothed with 320-400 grit emery cloth but do not try to salvage the shaft if nicks or wear is severe.

Scheme 75

Check the teeth on the gear (6). (Scheme 75) Minor nicks can be dressed off with an oilstone but replace the gear if any teeth are broken, cracked, or chipped. The bearing surface on the gear can be smoothed with 300-400 grit emery cloth if necessary.

Examine the carrier body (1) and pinion gears for wear or damage. The carrier will have to be replaced as an assembly if the body, pinion pins, or pinion gears are damaged.

Check the lock ring (4) and both thrust washers (2, 3) for wear or cracks. Replace them if necessary. Also replace the lock retaining ring if bent, distorted, or broken.

Scheme 76

Check condition of the shift forks (1, 2) and mode fork shift rail (2). (Scheme 76) Minor nicks on the shift rail can be smoothed with 320-400 grit emery cloth.

Scheme 77

Inspect the shift fork wear pads (3, 4). (Scheme 77) The mode and range fork pads are serviceable and can be replaced if necessary.

Check both of the sleeves for wear or damage, especially on the interior teeth. Replace the sleeves if wear or damage is evident.

REAR RETAINER AND EXTENSION HOUSING

Inspect the retainer components. Replace the bearing if rough or noisy. Check the retainer for cracks or wear in the bearing bore. Clean the retainer sealing surfaces with a scraper and 3M™ all purpose cleaner. This will ensure proper adhesion of the sealer during reassembly.

Inspect the retaining rings and washers. Replace any part if distorted, bent, or broken. Reuse is not recommended.

Inspect the extension housing seal and bushing. Replace both components if either show any sign of wear or damage.

FRONT OUTPUT SHAFT/FLANGE/DRIVE CHAIN

Check condition of the seal contact surfaces on the companion flange slinger. This surface must be clean and smooth to ensure proper seal life. Replace the flange nut and seal washer as neither part should be reused.

Inspect the shaft threads, sprocket teeth, and bearing surfaces. Minor nicks on the teeth can be smoothed with an oilstone. Use 320-400 grit emery to smooth minor scratches on the shaft bearing surfaces. Rough threads on the shaft can be chased if necessary. Replace the shaft if the threads are damaged, bearing surfaces are scored, or if any sprocket teeth are cracked or broken.

Examine the drive chain and shaft bearings. Replace the chain and both sprockets if the chain is stretched, distorted, or if any of the links bind. Replace the bearings if rough, or noisy.

Scheme 78

Inspect annulus gear condition carefully. The gear is only serviced as part of the front case. If the gear is damaged, it will be necessary to replace the gear and front case as an assembly. Do not attempt to remove the gear (2). (Scheme 78)

FRONT/REAR CASES AND FRONT RETAINER

Inspect the cases and retainer for wear and damage. Replace the input retainer seal; do not reuse it.

Check case condition. If leaks were a problem, look for gouges and severe scoring of case sealing surfaces. Also make sure the front case mounting studs are in good condition.

Check the front case mounting studs and vent tube. The tube can be secured with Loctite™ 271 or 680 if loose. The stud threads can be cleaned up with a die if necessary. Also check condition of the fill/drain plug threads in the rear case. The threads can be repaired with a thread chaser or tap if necessary. Or the threads can be repaired with Helicoil® stainless steel inserts if required.

OIL PUMP/OIL PICKUP

Examine the oil pump pickup parts. Replace the pump if any part appears to be worn or damaged. Do not disassemble the pump as individual parts are not available. The pump is only available as a complete assembly. The pickup screen, hose, and tube are the only serviceable parts and are available separately.

MAINSHAFT

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

Scheme 79

Scheme 80

Scheme 81

1. Install new sector shaft O-ring.
2. Install shift sector (1) in case. Lubricate sector shaft with transmission fluid before installation. see scheme 58 1 - RANGE HUB 2 - RANGE FORK
3. Assemble and install range fork (2) and hub (1). (Scheme 79) Be sure hub is properly seated in low range gear and engaged to the input gear.
4. Align and insert range fork pin in shift sector slot. 1 - DRIVE SPROCKET 2 - MODE HUB 3 - MAINSHAFT
5. Install assembled mainshaft (3). (Scheme 80) Be sure shaft is seated in pilot bearing and input gear. 1 - MODE SLEEVE 2 - MODE FORK AND RAIL
6. Install new pads on mode fork if necessary.
7. Insert mode sleeve (1) in mode fork mode fork. Be sure long side of sleeve is toward long end of shift rail (2). see scheme 61 1 - MODE SLEEVE 2 - MODE FORK AND RAIL
8. Install assembled mode fork and sleeve (1). (Scheme 81) Be sure fork rail goes through range fork and into case bore. Also be sure sleeve is aligned and seated on mainshaft hub. 1 - DETENT PLUNGER 2 - SEAL 3 - DETENT PLUG 4 - SPRING
9. Rotate sector to NEUTRAL position.
10. Install new O-ring on detent plug (3). see scheme 63
11. Lubricate detent plunger with transmission fluid or light coat of petroleum jelly.
12. Install detent plunger (1), spring (4), and plug (2).
13. Verify that plunger is properly engaged in sector.

Scheme 82

1. Lubricate front output shaft-sprocket assembly, drive chain and drive sprocket with transmission fluid.
2. Assemble drive chain (2) and front output shaft (1). (Scheme 82)
3. Start chain on mainshaft drive sprocket.
4. Guide front shaft into bearing and drive sprocket onto mainshaft drive gear. 1 - MODE SPRING
5. Install mode spring (1) on upper end of mode fork shift rail. see scheme 65

Scheme 83

Scheme 84

1. Install magnet in front case pocket (1). (Scheme 83) 1 - OIL PUMP 2 - O-RING
2. Assemble oil pickup screen, connecting hose, and tube.
3. Install new pickup tube O-ring (2) in oil pump (1). see scheme 67 1 - OIL PUMP 2 - PICKUP TUBE 3 - PICKUP SCREEN AND CONNECTOR
4. Insert oil pickup tube (2) in oil pump inlet. (Scheme 84)
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. 1 - ALIGNMENT BOLT AND WASHER (AT EACH END OF CASE)
6. Apply 3 mm (1/8 in.) wide bead of Mopar® Gasket Maker, or equivalent 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.
8. Install case attaching bolts. Alignment bolts at each end of case are only ones requiring washers (1). see scheme 69
9. Tighten case bolts to 27-34 N.m (20-25 ft. lbs.) torque.

REAR RETAINER

1. Apply 3 mm (1/8 in.) wide bead of Mopar® Gasket Maker, or equivalent 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 27-34 N.m (20-25 ft. lbs.).
3. Install new output shaft bearing snap-ring (2). see scheme 72 Lift mainshaft slightly to seat snap-ring in shaft groove, if necessary.
4. Apply 3 mm (1/8 in.) wide bead of Mopar® Gasket Maker, or equivalent 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 27-34 N.m (20-25 ft. lbs.).