Important: Because of manufacturing design changes,
the transfer case was manufactured with either 1st design components or 2nd design
components. When cleaning and inspecting the transfer case, follow the procedure for
that design level. The changes are for manufacturing purposes only and do not enhance
the performance of the transfer case. The following are the 2nd design components:
• | The oil pump suction pipe is nylon and the oil pump screen is serviced
only with the pipe. |
• | The 2/4 wheel drive synchronizer gear and drive sprocket sleeve
are net formed as 1 piece. |
Front Case Half
- Clean the front case half in cleaning solvent,
and air dry.
Notice: Refer to Machined Surface Damage Notice in the Preface section.
- Remove the sealer from the case sealing surfaces.
- Inspect the case for being broken or cracked.
- Inspect the front output shaft front bearing bore (8) for:
- Inspect the input shaft bearing bore (5) for:
- Replace the front case half if any of the above is found.
- Inspect the sealing surfaces (1) for damage.
- Repair small scratches or nicks with a soft stone.
- Inspect the front case to transmission case mounting surface for damage.
- Inspect the case threaded bolt holes (2) for damage.
- Repair any damaged threads.
- Inspect the transmission to transfer case studs (4) for damage.
- Replace any damaged studs. Refer to
Transfer Case Assemble
.
- Inspect the retaining ring (3) of the annulus gear to ensure it
is properly seated.
- Inspect the annulus gear (6) for the following:
• | Debris embedded in the root of the teeth |
- Replace the front case half if the annulus gear is damaged.
- Inspect the shift control lever shaft support bearing and seal (7)
for the following:
- Replace the shift control lever shaft support if it is faulty. Refer to
Transfer Case Disassemble
and
Transfer Case Assemble
.
- Inspect the location pins for being loose or missing.
- Repair or replace any damaged location pins.
- Inspect the front output shaft front bearing and the input shaft bearing
for the following:
- Replace the bearings if any of the above conditions are found. Refer to
Transfer Case Disassemble
and
Transfer Case Assemble
.
Rear Case Half
- Clean the rear case half in cleaning solvent,
and air dry.
Notice: Refer to Machined Surface Damage Notice in the Preface section.
- Remove the sealer from the case sealing surfaces.
- Inspect the case for being broken or cracked.
- Replace the case if it is broken or cracked.
- Inspect the sealing surfaces (1) for damage.
- Repair small scratches or nicks with a soft stone.
- Inspect the case threaded bolt holes for damage.
- Repair any damaged threads.
- Inspect the oil pump wear sleeve (5) for wear, for being loose
or missing, or for being damaged.
- Replace the oil pump wear sleeve if faulty.
- Inspect the front output shaft rear bearing (4) for the following:
- Replace the front output shaft rear bearing if any of the above conditions
are found. Refer to
Transfer Case Disassemble
and
Transfer Case Assemble
.
- Inspect the rear output shaft bearing for the following:
- Inspect for a spun bearing bore for the rear output shaft rear bearing.
- Replace the case if a bearing has spun.
- Inspect the retaining ring (2) for the rear output shaft rear bearing
for being bent or twisted.
- Replace a faulty retaining ring.
- Inspect the rear output shaft bushing (3) for scoring or wear.
- Replace a faulty rear output shaft bushing. Refer to
Transfer Case Disassemble
and
Transfer Case Assemble
.
Oil Pump, 1st Design
- Remove the oil pump suction pipe and the
oil pump suction hose from the oil pump screen.
- Clean the pipe, hose, and screen in cleaning solvent and air dry.
- If the screen is embedded with debris, replace the screen.
- Inspect the hose for cracking or tears.
- Replace the hose if it is faulty.
- Inspect the oil pump for the oil pump gears turning without binding.
- Replace the oil pump if there is any binding. Do not disassemble the oil
pump. The oil pump is serviced as an assembly.
Oil Pump, 2nd Design
- Clean
the oil pump suction pipe, with the screen, in cleaning solvent and air dry. Do not
remove the screen from the pipe.
- If the screen is embedded with debris, replace the suction pipe assembly.
- Inspect the oil pump for the oil pump gears turning without binding.
- Replace the oil pump if there is any binding. Do not disassemble the oil
pump. The oil pump is serviced as an assembly.
Rear Output Shaft
- Clean the rear output shaft in cleaning
solvent.
- Clean the rear output shaft oil galleries (2), and air dry.
Important: Do not attempt to smooth any roughness in
the bearing journals.
- Inspect the input gear pilot bearing surface (1) and the drive gear sleeve
journal surface (4) for the following:
- Inspect the rear output shaft splines (3) for damage or excessive
wear. Witness marks at the location of the gears is normal.
- Replace the rear output shaft if any of the above conditions are found.
High/Low Planetary Carrier
- Clean
the high/low planetary carrier in cleaning solvent. Do not disassemble the planetary
carrier.
- Air dry, and ensure all cleaning solvent is removed from the bearings
in the planetary gears (3). Do not spin the planetary gears with compressed
air.
- Inspect the planetary gears for chipped teeth.
- Inspect the planetary gears for debris embedded in the root of the teeth.
- Inspect for a washer (4) being on each side of the planetary gears.
- Inspect the low range teeth (1) for damage or excessive wear.
- Inspect the thrust washer surface (2) for scoring or excessive
wear.
- Replace the high/low planetary carrier if any of the above conditions
are found.
- Inspect the input gear thrust washers for excessive wear or scoring.
- Replace the thrust washers if they are faulty.
Drive Chain and Sprockets
- Clean the drive chain (1), drive
sprocket (3), and driven sprocket (2) in cleaning solvent and air dry.
- Inspect the drive chain (1) for the following:
• | Debris embedded in the links |
- Replace the chain if any of the above conditions are found.
- Inspect the driven sprocket (2) and the drive sprocket (3)
for the following:
• | Excessive worn gear surfaces, slight wear marks are normal |
• | Debris embedded in the root of the teeth |
- Replace the sprocket if any of the above conditions are found. The chain
and sprockets may be replaced separately.
- If 1st design, inspect the drive sprocket
sleeve journal surface for the following conditions:
- If 1st design, replace the sprocket sleeve if faulty.
- If 2nd design, inspect the 2/4 wheel drive synchronizer gear for chipped or
worn engagement teeth.
- If 2nd design, inspect the 2/4 wheel drive synchronizer gear journal surface
for the following conditions:
- If 2nd design, replace the 2/4 wheel drive synchronizer gear if faulty.
Front Output Shaft
- Clean the front output shaft in cleaning
solvent and air dry.
- Inspect the front output shaft rear bearing race (1) for the following:
- Inspect the front output shaft splines (2) for damage.
- Replace the front output shaft if it is damaged.
Input Gear
- Clean the input gear, with pilot bearing,
in cleaning solvent.
- Air dry, and ensure all solvent is removed from the pilot bearing.
- Inspect the pilot bearing (1) for the following:
- Replace the input gear pilot bearing if any of the above conditions are
found. Refer to
Transfer Case Disassemble
and
Transfer Case Assemble
.
- Inspect the input gear engagement teeth (2) for chips.
- Inspect the input gear for broken or damaged planetary teeth (3).
- Inspect the input gear for debris embedded in the root of the teeth.
- Inspect the input gear seal surface (4) for pitting or excessive
wear.
- Replace the input gear if any of the above conditions are found.
Shift System Components
- Clean
the following shift system components in cleaning solvent and air dry:
• | The high/low shift fork (1) |
• | The two/four wheel drive mode shift fork (3) |
• | The shift fork shaft (4) |
• | The control actuator lever shaft (5) |
• | The synchronizer gear, 1st design (6) |
• | The synchronizer assembly (7) |
- Inspect the shift fork shaft for straightness (4).
- Replace the shift fork shaft if it is not straight.
- If 1st design, inspect the synchronizer gear (6) for chipped or
worn engagement teeth.
- If 1st design, replace the gear if faulty.
- Inspect the pads (1) on the high/low shift fork for wear.
- Inspect the pin (2) on the shift fork for wear.
- Replace the shift fork if the pin is worn or the pads are worn.
- Inspect the two/four wheel drive mode shift fork roller (1) for the following:
- Inspect the shift fork for worn wear pads (3).
- Inspect the shift fork bearing (2) for being faulty.
- Replace the shift fork if the above conditions are found.
- Inspect the range sleeve for chipped or
excessive worn teeth (1).
- Inspect the shift fork collar (2) on the range sleeve for wear.
- Inspect the inner splines (3) of the range sleeve for excessive
looseness on the rear output shaft.
- Replace the range sleeve if the above conditions are found.
- Inspect the high/low shift fork roller slot (2)
on the control actuator lever shaft for wear or roughness.
- Inspect the bearing (1) and the seal surface on the control actuator
lever shaft for the following:
- Inspect the two/four wheel drive mode shift fork cam lobes (3)
on the control actuator lever shaft for wear or roughness.
- Inspect the detent plunger cam lobes (4) for wear or roughness.
- Replace the control actuator lever shaft if any of the above conditions
are found.
- Inspect the inner synchronizer ring (1)
for wear and roughness.
- Inspect the middle synchronizer ring (2) friction material for
wear or damage.
- Inspect the outer synchronizer ring (3) for wear.
- Inspect the synchronizer sleeve (4) for the following conditions:
• | Wear on the engagement teeth |
• | Wear in the insert notches |
- Inspect the synchronizer hub (6) for the following conditions:
• | Loose fit on the rear output shaft |
• | Broken or damaged insert springs (5 and 8) |
- Replace the synchronizer assembly if any of the above parts are faulty.