Hummer H1 (2002+). Manual - part 91

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 Transmission/Transfer Case  5-163

®

05745159

Figure 5-105:   Sector Shaft Bushing and O-Ring 

Removal

29. Remove bolts attaching front retainer to front case. Then

remove retainer by prying it loose with screwdriver
positioned in retainer slot (Figure 5-106).

Figure 5-106:   Front Retainer Removal

30. Remove snap ring that secures input gear in bearing

(Figure 5-107).

31. Remove input gear and low range planetary as assembly.

Tap input gear with rawhide or plastic mallet to free it
from bearing.

32. Disassemble input gear and low range planetary as

follows:

a.

Remove retaining ring that secures input gear in low 
range planetary (Figure 5-108).

b.

Remove lock ring and front thrust washer (Figure 5-109).

c.

Remove input gear and rear thrust washer from low 
range planetary (Figure 5-109).

Figure 5-107:   Input Gear Snap Ring Removal

Figure 5-108:   Input Gear Retaining Ring Removal

SHAFT

SECTOR

BUSHING

O-RING

FRONT

RETAINER

RETAINER

SLOT

SNAP RING

INPUT GEAR

INPUT GEAR

LOW RANGE

PLANETARY

RETAINING

RING

5-164

Transmission/Transfer Case

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Figure 5-109:   Input/Low Range Planetary Gear 

Disassembly Sequence

33. Remove and disassemble differential as follows:

a.

Scribe or paint mark front and rear cases for assembly 
reference (Figure 5-110).

b.

Remove case bolts (Figure 5-111).

c.

Pry front and rear cases apart with two screwdrivers 
(Figure 5-112).

d.

Remove planet gears and thrust washers (Figure 5-113).

e.

Remove sprocket and mainshaft gears as assembly 
(Figure 5-114).

34. Remove front output shaft front bearing seal with pry tool

(Figure 5-115).

Figure 5-110:   Marking Differential Cases for 

Assembly Reference

Figure 5-111:   Differential Case Bolt Removal

Figure 5-112:   Separating Differential Cases

Figure 5-113:   Planet Gear Locations In Bottom Case

LOW RANGE

PLANETARY

INPUT
GEAR

LOCK RING

FRONT

THRUST

WASHER

REAR

THRUST

WASHER

REAR CASE

FRONT CASE

ALIGNMENT SCRIBE

OR PAINT MARK

CASE BOLTS

FRONT CASE

REAR CASE

SPROCKET

GEAR

PLANET

GEARS (6)

FRONT

CASE

THRUST

WASHERS (12)

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 Transmission/Transfer Case  5-165

®

05745159

Figure 5-114:   Mainshaft and Sprocket Gear 

Removal

Figure 5-115:   Removing Front Output Shaft Seal

TRANSFER CASE CLEANING AND 
INSPECTION

Clean the transfer case components thoroughly with standard
parts cleaning solvent. Remove all traces of sealer from the
case and retainer sealing surfaces.

Clean the oil pickup screen with solvent and dry it with com-
pressed air. Also use compressed air to remove solvent residue
from all oil feed passages and channels.

Geartrain

The differential pinion gears and thrust washers are serviceable
components and can be replaced if worn or damaged. The dif-
ferential cases are also serviceable but must be replaced as a set
if either case is damaged.

Inspect the mainshaft splines, gear teeth and bearing surfaces
carefully for evidence of wear, or damage. Replace the shaft if
necessary. Do not attempt to salvage it if damaged.

The range and mode forks are serviced as assemblies. Replace
either part if damaged. However, the nylon pads in the forks
can be replaced if worn, or cracked.

Inspect the transfer case snap rings closely. Do not attempt to
salvage a distorted snap ring by straightening or reshaping it.
Replace any snap ring that is distorted, or worn.

Inspect the low range planetary, input gear and thrust washer,
retainer, and snap ring. The low range planetary is serviced as
an assembly only. Replace it if the case or pinions are dam-
aged.

During inspection, also make sure the seal surface of the input
gear is in good condition. Minor nicks on this surface can be
reduced with crocus cloth. However, replace the gear if the seal
surface is severely scored or worn.

Check condition of the low range annulus gear (Figure 5-116).
Replace the front case and gear as an assembly if the gear is
damaged. The annulus gear is not serviced separately.

The speedometer tone wheel should be replaced if worn,
cracked, or spline teeth are worn.

Inspect the differential gears, thrust washers and case halves.
Replace the mainshaft gear if the gear teeth or the brass ring on
the underside of the gear are damaged. Replace the differential
as an assembly if the gears, case halves, or the pins in the lower
case half are damaged.

Inspect the case halves, extension housing, and both retainers
for cracks, porosity, or damaged sealing surfaces. Inspect the
shafts, gears, chain and shift components for wear or damage.

Inspect all of the transfer case bearings for wear, roughness,
pitting, or galling. Replace worn or damaged bearings.

MAINSHAFT GEAR

SPROCKET GEAR

SHAFT

SEAL

FRONT CASE

PRY TOOL

5-166

Transmission/Transfer Case

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Figure 5-116:   Annulus Gear Location In Front Case

Oil Pump

The oil pump is not a serviceable component. Replace the
pump as an assembly if the gear teeth are worn, or if the pump
has become damaged.

Bearings and Seals

The transfer case seals should be replaced during overhaul.
Use new seals in the oil pump, input gear bearing retainer,
front case, and extension housing. Also replace the yoke seal
washer and detent plug O-ring.

FRONT OUTPUT SHAFT BEARING AND SEAL 
REPLACEMENT

1.

Remove snap ring securing shaft front bearing in front 
case (Figure 5-117).

2.

Tap old bearing out rear of front case with plastic or raw
hide mallet.

3.

Install new bearing with tool handle J–8092 and installer
tool J–33833  (Figure 5-118).

4.

Lubricate new bearing with Dexron III.

5.

Install new shaft seal with seal installer J–38869
(Figure 5-119). Then lubricate seal lip with Dexron III.

6.

Remove front output shaft rear bearing from rear case as
follows:

a.

Clamp rear case to bench with wood blocks and C-
clamps.

b.

Pull bearing using slide hammer, adapter J–2619-01,
and puller J–26369 (Figure 5-120).

c.

Install new bearing with tool handle J–8092 and
installer J–33832  (Figure 5-121). The rear bearing
bore is chamfered at the top. Install the bearing so it is
flush with the chamfer lower edge.

CAUTION:  Do not bottom the bearing in the bore. This will
block the oil feed hole in the rear case bearing bore.

Figure 5-117:   Front Output Shaft Front Bearing Snap 

Ring Removal/Installation

FRONT CASE

ANNULUS GEAR

FRONT CASE

BEARING

SNAP RING

FRONT OUTPUT

SHAFT FRONT

BEARING