Content .. 2879 2880 2881 2882 ..
Chevrolet Silverado / GMC Sierra. Manual - part 2881
TRANSFER CASE CLUNK IN 4LO
TRANSFER CASE WILL NOT SHIFT
the high/low clutch
Inspection.
2. Replace the high/low clutch if worn. Refer to Transfer
Case Disassemble and Transfer Case Assemble.
Cause
Correction
DEFINITION: During acceleration or deceleration, a clunk is heard or felt in the transfer
case while in the 4LO range only.
Review the Symptoms - Transfer Case and perform the necessary inspections.
High/low planetary carrier
assembly
1. Inspect for the following conditions:
Excessively worn planetary gears
The planetary gears loose in the planetary carrier
The input shaft for missing thrust washers or
excessive thrust end play in the carrier
Excessively worn high/low clutch engagement teeth
on the carrier
Refer to High/Low Planetary Carrier Cleaning
and Inspection .
2. Replace the high/low planetary if any of the above
conditions are found. Refer to Transfer Case
Disassemble and Transfer Case Assemble.
High/low internal gear
1. Inspect the high/low internal gear to front case fit for any
looseness.
2. Replace the front case half if the high/low internal gear is
loose. Refer to Transfer Case Disassemble and
Transfer Case Assemble.
High/low clutch
1. Inspect the high/low clutch engagement teeth for
excessive wear.
2. Inspect the high/low clutch to rear output shaft splines for
excessive wear.
3. Replace the high/low clutch if faulty. Refer to Transfer
Case Disassemble and Transfer Case Assemble.
2008 Chevrolet Silverado 1500
2008 TRANSMISSION Transfer Case - MP 1625/1626-NQF - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra &
Silverado
Cause
Correction
DEFINITION: While shifting from HI range to LO range, there is gear clashing or no HI
range; or the transfer case will not shift from 2 wheel drive to 4 wheel drive.
Review the Symptoms - Transfer Case and perform the necessary inspections.
Mode shift clash
1. Disassemble the transfer case. Refer to Transfer Case
Disassemble.
2. Inspect the synchronizer for being faulty. Refer to
Two/Four Wheel Drive Shift Components Cleaning
and Inspection.
3. Replace the synchronizer if faulty. Refer to Transfer
Case Assemble.
Mode block
1. Disassemble the transfer case. Refer to Transfer Case
Disassemble.
2. Inspect the synchronizer sleeve for sliding freely on the
synchronizer hub.
3. Inspect the synchronizer sleeve or synchronizer hub for
being faulty.
4. Replace the synchronizer sleeve or synchronizer hub if
faulty. Refer to Transfer Case Assemble.
If the symptoms occur during cold temperatures, flush and fill
the front axle with synthetic fluid. Refer to Front Axle
Lubricant Level Inspection (9.25 Inch Axle) .
High/low shift fork spring
assembly
1. Inspect the high/low shift fork spring assembly for the
following conditions:
Worn high/low shift fork pin
Worn cam
Broken spring
Refer to High/Low Shift Components Cleaning
and Inspection .
2. Replace the following components if found faulty:
The high/low shift fork spring assembly
The high/low shift fork pin
2008 Chevrolet Silverado 1500
2008 TRANSMISSION Transfer Case - MP 1625/1626-NQF - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra &
Silverado
Refer to High/Low Shift Fork Replacement .
High/low shift fork
1. Inspect the high/low shift fork for the following
conditions:
Worn shift fork pads
Cracked or bent shift fork
Refer to High/Low Shift Components Cleaning
and Inspection .
2. Replace the following components if found faulty:
The shift fork pads
The shift fork
Refer to High/Low Shift Fork Replacement .
High/low clutch
1. Inspect the high/low clutch for the following conditions:
Engagement teeth for burrs or damage
Sliding freely on the rear output shaft
The high/low clutch collar for excessive wear
Refer to High/Low Shift Components Cleaning
and Inspection .
2. Replace the high/low clutch if faulty. Refer to Transfer
Case Disassemble and Transfer Case Assemble.
Input shaft pilot bearing
assembly
1. Inspect for the following conditions:
Failed input shaft pilot bearing in the input shaft
Journal on the rear output shaft for excessive wear
or damage
Refer to Rear Output Shaft Cleaning and
Inspection and Front Output Shaft and Input
Shaft Cleaning and Inspection .
2. Replace the bearing if faulty. Refer to Input Shaft Pilot
Bearing Replacement (Heavy Duty and Super Heavy
Duty) .
3. Replace the rear output shaft if damaged. Refer to
2008 Chevrolet Silverado 1500
2008 TRANSMISSION Transfer Case - MP 1625/1626-NQF - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra &
Silverado
TRANSFER CASE JUMPS OUT OF GEAR
Transfer Case Disassemble and Transfer Case
Assemble.
High/low planetary carrier
assembly
1. Inspect the high/low planetary engagement teeth for burrs
or damage. Refer to High/Low Planetary Carrier
Cleaning and Inspection.
2. Replace the high/low planetary carrier assembly if faulty.
Refer to Transfer Case Disassemble and Transfer
Case Assemble.
Cause
Correction
DEFINITION: Loss of the transfer case drive torque during deceleration, acceleration or
under load.
Review the Symptoms - Transfer Case and perform the necessary inspections.
High/low shift fork pads
1. Inspect the high/low shift fork pads for wear. Refer to
High/Low Shift Components Cleaning and
Inspection.
2. Replace the fork pads if worn. Refer to Transfer Case
Disassemble and Transfer Case Assemble.
Faulty high/low shift fork
1. Inspect the high/low shift fork for being damaged. Refer
to High/Low Shift Components Cleaning and
Inspection.
2. Replace the shift fork if faulty. Refer to High/Low Shift
Fork Replacement.
High/low shift fork spring
assembly
1. Inspect the high/low shift fork spring assembly for the
following conditions:
Worn high/low shift fork pin
Worn cam
Broken spring
Refer to High/Low Shift Components Cleaning
and Inspection .
2. Replace the following components if found faulty:
The high/low shift fork spring assembly
2008 Chevrolet Silverado 1500
2008 TRANSMISSION Transfer Case - MP 1625/1626-NQF - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra &
Silverado
Content .. 2879 2880 2881 2882 ..