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Transfer Case - Servicing Chevrolet Avalanche I

Transfer Case 18 illustrations ~1224 words

APPLICATION

ApplicationTransfer Case Model (RPO Code)
AvalancheNVG 246 (NP8)
Suburban & Tahoe
Light DutyNVG 246 (NP8)
Heavy DutyBW 4482 (NR4)

TRANSFER CASE APPLICATION

SERVICE INTERVALS

Every 12 months or at engine oil change intervals, check front axle and transfer case and add lubricant when necessary. A fluid loss could indicate a problem; check and have it repaired, if needed. On manual shift transfer case, oil the control lever pivot point. Check vent hose at transfer case for kinks and proper installation. More frequent lubrication may be required in the case of frequent off-road use. Change transfer case fluid every 50,000 miles under normal servicing conditions.

CHECKING FLUID LEVELS

Remove filler plug located on rear of transfer case. (Scheme 1) Fluid should be within.2" (5 mm) of bottom of filler plug hole. If fluid is low, fill with appropriate type fluid. See RECOMMENDED FLUIDS. Reinstall filler plug. Tighten to specification. See TORQUE SPECIFICATIONS.

Scheme 1

Scheme 1: CHECKING FLUID LEVELS
Scheme 1: CHECKING FLUID LEVELS

RECOMMENDED FLUIDS

ApplicationFluid Type
BW 4482Dexron-III ATF
NVG 246Auto-Trak II

TRANSFER CASE FLUID TYPE

FLUID CAPACITIES

ApplicationQts. (L)
BW 44821.5 (1.4)
NVG 2462.0 (1.9)
(1) Approximate capacity is listed.
(1)Approximate capacity is listed.

TRANSFER CASE FLUID CAPACITIES (1)

DRAINING & REFILLING

CAUTIONUse only drain and fill plugs that are made from aluminum. Steel or brass plugs are not compatible with magnesium case.

Note. When performing the following procedures, use only hand tools to remove and install drain and fill plugs.

  1. Raise and support vehicle. Remove transfer case shield (if equipped). See «TRANSFER CASE SHIELD»(/chevrolet/avalanche/i-2001-2006/remont/transfer-case/#transfer-case-servicing) under REMOVAL & INSTALLATION. Remove fill and drain plugs. (Scheme 1) Allow fluid to drain.
  2. Install drain plug. Tighten to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/avalanche/i-2001-2006/remont/transfer-case/#transfer-case-servicing__torque-specifications). Fill the transfer case to the bottom of the fill plug hole with appropriate fluid. See «RECOMMENDED FLUIDS»(/chevrolet/avalanche/i-2001-2006/remont/transfer-case/#transfer-case-servicing__recommended-fluids). Install fill plug. Tighten to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/avalanche/i-2001-2006/remont/transfer-case/#transfer-case-servicing__torque-specifications). Install the transfer case shield. See «TRANSFER CASE SHIELD»(/chevrolet/avalanche/i-2001-2006/remont/transfer-case/#transfer-case-servicing) under REMOVAL & INSTALLATION. Lower vehicle.

REMOVAL & INSTALLATION

WARNINGVehicle is equipped with Supplemental Inflatable Restraint (SIR) system. When servicing vehicle, use care to avoid accidental air bag deployment. SIR system-related components are located in various locations throughout interior and exterior of vehicle, depending on application. Do not use electrical test equipment on or near these circuits. If necessary, deactivate SIR system before servicing components. See appropriate AIR BAG DEACTIVATION PROCEDURES in GENERAL INFORMATION.
CAUTIONWhen battery is disconnected, vehicle computer and memory systems may lose memory data. Driveability problems may exist until computer systems have completed a relearn cycle. See COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION before disconnecting battery.

Note. Use correct fastener in the correct location. Replacement fasteners must be correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

Removal (BW 4482)

Note. The front output shaft seal is a 2-piece internal seal. The inner seal race is a force fit on front output shaft.

  1. Raise and support vehicle. Remove transfer case shield. See «TRANSFER CASE SHIELD»(/chevrolet/avalanche/i-2001-2006/remont/transfer-case/#transfer-case-servicing).
  2. Remove front drive shaft. See appropriate DRIVE SHAFTS & UNIVERSAL JOINTS article in DRIVELINE/AXLES.
  3. Insert a flat-tipped screwdriver behind inner race of the seal. (Scheme 2)
  4. Pry inner race forward.
  5. Using a small pry bar, move inner seal race forward on front output shaft.
  6. Remove inner seal race from front output shaft. (Scheme 3)
  7. Insert a flat-tipped screwdriver or a small pry bar between outer lip of front output shaft seal and transfer case.
  8. Remove remaining part of front output shaft seal from transfer case.

Scheme 2

Scheme 2
Scheme 2

Scheme 3

Scheme 3
Scheme 3

Installation (BW 4482)

  1. Install appropriate output shaft installer (2) to driver handle (1). (Scheme 4)
  2. Install the seal onto output shaft installer and install seal into transfer case.
  3. Install front drive shaft. See appropriate DRIVE SHAFTS & UNIVERSAL JOINTS article in DRIVELINE/AXLES.
  4. Check transfer case fluid level, and add if necessary. See «LUBRICATION»(/chevrolet/avalanche/i-2001-2006/remont/transfer-case/#transfer-case-servicing).
  5. Install transfer case shield. See «TRANSFER CASE SHIELD»(/chevrolet/avalanche/i-2001-2006/remont/transfer-case/#transfer-case-servicing). Lower vehicle.

Scheme 4

Scheme 4
Scheme 4

Removal (NVG 246)

  1. Raise and support vehicle. Remove transfer case shield. See «TRANSFER CASE SHIELD»(/chevrolet/avalanche/i-2001-2006/remont/transfer-case/#transfer-case-servicing).
  2. Remove front drive shaft. See appropriate DRIVE SHAFTS & UNIVERSAL JOINTS article in DRIVELINE/AXLES.
  3. Insert a flat-tipped screwdriver into inner race. (Scheme 5)
  4. Pry inner race back. Remove the dust shield from output shaft.
  5. Insert a small pry bar into inner race. (Scheme 6)
  6. Remove the inner race from the seal.
  7. Insert a flat-tipped screwdriver or a small pry bar in space between outer race of seal and transfer case. (Scheme 7)
  8. Remove outer part of the seal. (Scheme 8)

Scheme 5

Scheme 5
Scheme 5

Scheme 6

Scheme 6
Scheme 6

Scheme 7

Scheme 7
Scheme 7

Scheme 8

Scheme 8
Scheme 8

Installation (NVG 246)

  1. Install appropriate output shaft installer (2) to driver handle (1). (Scheme 4)
  2. Install seal onto output shaft installer, and install seal into transfer case.
  3. Install front drive shaft. See appropriate DRIVE SHAFTS & UNIVERSAL JOINTS article in DRIVELINE/AXLES.
  4. Check transfer case fluid level, and add as necessary. See «LUBRICATION»(/chevrolet/avalanche/i-2001-2006/remont/transfer-case/#transfer-case-servicing).
  5. Install transfer case shield. See «TRANSFER CASE SHIELD»(/chevrolet/avalanche/i-2001-2006/remont/transfer-case/#transfer-case-servicing). Lower vehicle.
  1. Raise and support vehicle. Remove transfer case shield. See «TRANSFER CASE SHIELD»(/chevrolet/avalanche/i-2001-2006/remont/transfer-case/#transfer-case-servicing).
  2. Remove rear drive shaft. See appropriate DRIVE SHAFTS & UNIVERSAL JOINTS article in DRIVELINE/AXLES.
  3. Remove rear output shaft seal by prying it out with a flat-tipped screwdriver. (Scheme 9)

Scheme 9

Scheme 9
Scheme 9
  1. Install a NEW output shaft seal using appropriate seal remover/installer. (Scheme 10)
  2. Install front drive shaft. See appropriate DRIVE SHAFTS & UNIVERSAL JOINTS article in DRIVELINE/AXLES.
  3. Check transfer case fluid level, and add if necessary. See «LUBRICATION»(/chevrolet/avalanche/i-2001-2006/remont/transfer-case/#transfer-case-servicing).
  4. Install transfer case shield. See «TRANSFER CASE SHIELD»(/chevrolet/avalanche/i-2001-2006/remont/transfer-case/#transfer-case-servicing). Lower vehicle.

Scheme 10

Scheme 10
Scheme 10
  1. Raise and support vehicle. Remove transfer case shield (if equipped). See «TRANSFER CASE SHIELD»(/chevrolet/avalanche/i-2001-2006/remont/transfer-case/#transfer-case-servicing).
  2. Remove rear drive shaft. See appropriate DRIVE SHAFTS & UNIVERSAL JOINTS article in DRIVELINE/AXLES.
  3. Remove rear output shaft seal. (Scheme 11)
  4. Inspect rear output shaft bushing for scoring or wear.
  5. Replace bushing as necessary using the following method: Install finger section of appropriate bushing remover/installer in front of bushing. (Scheme 12) Install tube and forcing screw to finger section. Ensure forcing screw is backed out. Using wrench on forcing screw, remove rear output shaft bushing.

Scheme 11

Scheme 11
Scheme 11

Scheme 12

Scheme 12
Scheme 12
  1. Install a NEW output shaft bushing using the following method: Install bushing or the finger section of appropriate bushing remover/installer. (Scheme 13) Install finger section to main body of appropriate remover/installer. Position bushing and tool to case. Install bushing using a hammer and appropriate bushing remover/installer. NOTE: Ensure drain hole on boot of rear output shaft seal is facing down toward ground.
  2. Install a NEW front output shaft seal using appropriate seal remover/installer. (Scheme 14)
  3. Install rear drive shaft. See appropriate DRIVE SHAFTS & UNIVERSAL JOINTS article in DRIVELINE/AXLES.
  4. Check transfer case fluid level, and add as necessary. See «LUBRICATION»(/chevrolet/avalanche/i-2001-2006/remont/transfer-case/#transfer-case-servicing).
  5. Install transfer case shield. See «TRANSFER CASE SHIELD»(/chevrolet/avalanche/i-2001-2006/remont/transfer-case/#transfer-case-servicing). Lower vehicle.

Scheme 13

Scheme 13
Scheme 13

Scheme 14

Scheme 14
Scheme 14
  1. Raise and suitably support the vehicle.
  2. Disconnect the speed sensor electrical connector (4). (Scheme 15)
  3. Remove the speed sensor and "O" ring. (Scheme 16) Discard the "O" ring.

Scheme 15

Scheme 15
Scheme 15

Scheme 16

Scheme 16
Scheme 16
  1. Install the speed sensor with a NEW "O" ring. (Scheme 16) Tighten sensor to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/avalanche/i-2001-2006/remont/transfer-case/#transfer-case-servicing__torque-specifications).
  2. Connect the speed sensor electrical connector (4). (Scheme 15)
  3. Lower vehicle.

Removal & Installation (NVG 246 - Front)

  1. Raise and support vehicle. Remove transfer case shield. See «TRANSFER CASE SHIELD»(/chevrolet/avalanche/i-2001-2006/remont/transfer-case/#transfer-case-servicing). Disconnect front speed sensor electrical connector (5). (Scheme 17) Remove front speed sensor.
  2. To install, reverse removal procedure. Tighten sensor to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/avalanche/i-2001-2006/remont/transfer-case/#transfer-case-servicing__torque-specifications). Install transfer case shield. See «TRANSFER CASE SHIELD»(/chevrolet/avalanche/i-2001-2006/remont/transfer-case/#transfer-case-servicing). Lower vehicle.

Scheme 17

Scheme 17
Scheme 17

Removal & Installation (NVG 246 - Rear; Left Or Right)

  1. Raise and support vehicle. Disconnect right rear (3) or left rear (4) speed sensor electrical connector. (Scheme 17) Remove speed sensor(s).
  2. To install, reverse removal procedure. Tighten sensor(s) to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/avalanche/i-2001-2006/remont/transfer-case/#transfer-case-servicing__torque-specifications). Connect speed sensor electrical connector(s). (Scheme 17) Lower vehicle.
  1. Raise and support vehicle.
  2. Remove transfer case shield screws or bolts.
  3. Remove transfer case shield. (Scheme 18)
  4. To install, position transfer case shield.
  5. Install transfer case shield screws or bolts. (Scheme 18) Tighten fasteners to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/avalanche/i-2001-2006/remont/transfer-case/#transfer-case-servicing__torque-specifications).

Scheme 18

Scheme 18
Scheme 18

TORQUE SPECIFICATIONS

ApplicationFt. Lbs. (N.m)
Drain & Fill Plugs
BW 448218 (25)
NVG 24615 (20)
Transfer Case Speed Sensors
BW 448213 (17)
NVG 24611 (15)
Transfer Case Shield Bolts/Screws15 (20)

TORQUE SPECIFICATIONS

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