Chevrolet Silverado / GMC Sierra. Service manual — part 2852

HIGH/LOW PLANETARY CARRIER CLEANING AND INSPECTION

Clean all components in cleaning solvent and air dry.

1

Transfer Case Front Output Shaft Drive Sprocket
Bearing Assembly
Tip: Replace the bearings if roughness, brinelling, or
pitting is detected. Refer to Front Output Shaft
Drive Sprocket Bearing Replacement.

2

Transfer Case Front Output Shaft Drive Sprocket
Bearing Surface
Tip: If the bearing is removed, inspect for excessive
wear, damage, or if the bearing has spun in the bore.

3

Transfer Case Two/Four Wheel Drive Synchronizer
Sleeve Engagement Teeth
Tip: Inspect the engagement teeth for chips or
excessive wear.

4

Transfer Case Front Output Shaft Drive Sprocket
Tip:

Inspect for chipped teeth, excessively worn
gear surfaces, and debris embedded in the root
of the teeth.

Witness marks at the location of the chain is
normal.

5

Transfer Case Front Output Shaft Driven Sprocket
Tip:

Inspect for chipped teeth, excessively worn
gear surfaces, and debris embedded in the root
of the teeth.

Witness marks at the location of the chain is
normal.

6

Transfer Case Front Output Shaft Drive Chain
Assembly
Tip: Inspect for loose link pins, binding or stiff links,
debris embedded in the links, or worn teeth surfaces.

2008 Chevrolet Silverado 1500

2008 TRANSMISSION Transfer Case - MP 1222/1225/1226-NQG - Cab & Chassis Sierra, Cab & Chassis Silverado,

Sierra & Silverado

Fig. 33: View Of High/Low Planetary Carrier Inspection Points
Courtesy of GENERAL MOTORS CORP.

Callout

Component Name

Preliminary Procedure

Inspect all components or sub-components and perform any repair procedure
necessary to fix the damage. If the damage cannot be repaired, replace the component
or sub-component as indicated.

Clean all components in cleaning solvent and air dry. Do not spin the planetary gears
with compressed air.

The high/low planetary carrier is only serviced as an assembly.

Transfer Case High/Low Clutch Engagement

2008 Chevrolet Silverado 1500

2008 TRANSMISSION Transfer Case - MP 1222/1225/1226-NQG - Cab & Chassis Sierra, Cab & Chassis Silverado,

Sierra & Silverado

HIGH/LOW SHIFT COMPONENTS CLEANING AND INSPECTION

Fig. 34: View Of High/Low Shift Components Inspection Points
Courtesy of GENERAL MOTORS CORP.

1

Teeth
Tip: Inspect the engagement teeth for chips or
excessive wear.

2

Transfer Case Planetary Carrier Sun Gear
Thrust Washer Surface
Tip: Inspect the thrust washer surface for
scoring or excessive wear.

3

Transfer Case High/Low Planetary Carrier
Pinion Gear Thrust Washer
Tip: Inspect for a thrust washer being on each
side of the planetary gears.

4

Transfer Case High/Low Planetary Pinion Gear
Tip: Inspect for broken, damaged, or debris
embedded in the root of the teeth.

2008 Chevrolet Silverado 1500

2008 TRANSMISSION Transfer Case - MP 1222/1225/1226-NQG - Cab & Chassis Sierra, Cab & Chassis Silverado,

Sierra & Silverado

Callout

Component Name

Preliminary Procedure

Inspect all components or sub-components and perform any repair procedure
necessary to fix the damage. If the damage cannot be repaired, replace the component
or sub-component as indicated.

Clean all components in cleaning solvent and air dry.

1

Transfer Case High/Low Clutch Inner Splines
Tip: Inspect the inner splines for excessive
looseness on the rear output shaft.

2

Transfer Case High/Low Clutch Teeth
Tip: Inspect the engagement teeth for chips or
excessive wear.

3

Transfer Case High/Low Shift Fork Collar
Tip: Inspect the shift fork collar for wear.

4

Transfer Case High/Low Shift Fork Inserts
Tip: Inspect the inserts for wear.

5

Transfer Case High/Low Shift Fork
Tip: Inspect for cracks, broken areas, or other
damage. The component must be replaced if
damage is found.

6

Transfer Case Control Actuator Shaft
Tip: Inspect the shaft for straightness.

7

Transfer Case Shift Fork Spring
Tip: Inspect the spring for breakage.

8

Transfer Case High/Low Shift Fork Pin
Tip: Inspect the pin for wear.

9

Transfer Case Two/Four Wheel Drive Mode
Cam Lobes
Tip: Inspect the cam lobes for wear or
roughness.

10

Transfer Case Shift Detent Plunger Cam Lobes
Tip: Inspect the cam lobes for wear or
roughness.

11

Transfer Case Shift Detent Lever Shaft
Tip: Inspect for scoring, brinelling, pitting, or
excessive wear.

2008 Chevrolet Silverado 1500

2008 TRANSMISSION Transfer Case - MP 1222/1225/1226-NQG - Cab & Chassis Sierra, Cab & Chassis Silverado,

Sierra & Silverado