Hummer H1 (2006+). Manual - part 275

9-78 Axles, Suspension and Frame

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Frame Repairs

Cracks

NOTE: All frame welding should be heli-arc type.

1.

Cracks not extending across two adjacent faces of the frame rail may be welded.

• Stop-drill crack with 1/8-inch (3 mm) drill (Figure  9-123)

• Vee-notch crack (Figure  9-123)

• Heli-arc weld crack with Mig or Tig welder (using a filler metal in accordance with AWS A5.18) (Figure  9-123)

• If reinforcement or fishplate is to be added, grind weld to a flat surface (Figure  9-123)

• A reinforcement or fishplate should be added to a frame rail with a crack in the bottom face 

• Longitudinal welding can be performed on any frame rail face

2.

Welded reinforcements or fishplates should not be less than 6-inches (15.2 cm) in length along the frame rail.

3.

Bolt on reinforcements or fishplates should not be less than 8-inches (20.3 mm) in length. The long bottom edge of the
fishplate should be heli-arc lap welded to the frame component.

4.

Puncture holes only in the side faces of the frame rails may be repaired with a combinations of a fishplates and/or
reinforcements. Welded type should only be used. Puncture holes in the bottom face are not repairable and therefore the frame
rail should be replaced.

5.

Bolted-on repairs should use grade 8 bolts with hardened washers and nuts. Use the proper torque when tightening the nuts. 

Figure 9-123:   Crack Repair

V-NOTCH

CRACK

HELI-ARC

WELD CRACK

STOP DRILL WITH

1/8-INCH (3MM)

DRILL

GRIND WELD FLAT

IF ADDING A 

REINFORCEMENT

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 Axles, Suspension and Frame  9-79

Bends

1.

Do not attempt to repair a bend when:

• Buckling to a height of 1/4-inch (6 mm) on any one face of the frame rail is involved. 

• The bending also includes more than minor twisting.

• The frame rail is bent in two directions. 

• The bending involves a collapse of one or more faces of the frame rail at a suspension or body attachment point. 

Straightening

1.

When performing a straightening repairs with the frame on the vehicle:

• Use spreader plates or wood blocking to distribute chain force to avoid damage to frame box section.

• Be sure to loosen sufficient length of frame to allow frame force points to move without causing other damage.

• Restrain vehicle movement in both directions along line of force application.

2.

Vertical bends, except at the end sections, require removal of the frame rail from the vehicle.

3.

Application of bulk heating to the frame components is not authorized, the metal properties will be irreversibly degraded.

4.

At the conclusion of a bend repair, carefully inspect the welds in the vicinity of the repair and area of force application. Any
evidence of cracking or chipping of the welds must be repaired.

BRUSHGUARD

Removal

1.

Have an assistant hold the brushguard while removing the four bolts, nuts and the eight washers securing the brush guard 
mount brackets to the frame brackets (Figure  9-124).

2.

Remove the brushguard assembly.

Figure 9-124:   Brushguard Installation (Vehicle w/Winch Shown)

Installation

1.

Using an assistant, place the brushguard on the frame brackets or the bumper if the vehicle does not have a winch and install
the four bolts, nuts and the washers. Torque the hardware to 81-99 lb-ft. (110-134 N•m).

2.

Check the brushguard for level and equal, side to side, spacing from the hood. If adjustment is necessary, loosen the four
alignment bolts and move the brush guard accordingly. Tighten the alignment hardware to 81-99 lb-ft. (110-134 N•m).

3.

Remove the lock pins and check for free movement and clearance to the roller fairlead if equipped. Adjust as needed and
reinstall the lock pins.

MOUNT

BRACKET

ALIGNMENT

HARDWARE

LOCK

PIN

9-80 Axles, Suspension and Frame

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DRIVELINE PROTECTION 

Skid Plate Replacement

Removal

1.

Remove the locknuts, washers, bolts and the washers securing the skid plate to the front shield (Figure  9-125).

NOTE: Go to step 3 for vehicles equipped with a winch.

2.

Remove the locknuts, washers, bolts, washers and the skid plate from the front bumper.

3.

Remove the locknuts, washers, bolts, washers and the winch skid plate from the winch bumper.

Figure 9-125:   Skid Plate Mounting

Installation

NOTE: Go to step 2 for vehicles equipped with a winch.

1.

Install the skid plate on the front bumper with the bolts, washers and the locknuts. Tighten the locknuts to 24 lb-ft. (33 N•m)
(Figure  9-125).

2.

Install the winch skid plate on the winch bumper with the bolts, washers and the locknuts (Figure  9-125). Tighten the locknuts
to 24 lb-ft. (33 N•m).

3.

Secure the skid plate to the front shield with the bolts, washers and the locknuts. Tighten the locknuts to 24 lb-ft. (33 N•m).

WINCH BUMPER

WINCH SKID PLATE

SKID PLATE

FRONT SHIELD

FRONT BUMPER

FRONT

 SHIELD

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 Axles, Suspension and Frame  9-81

Front Shield Replacement

Removal

1.

Remove the locknuts, washers and the bolts securing the front shield to the front crossmember and the intermediate shield 
(Figure  9-126).

2.

Remove the three locknuts, washers and the bolts from the skid plate and the front shield, remove the front shield.

Installation

1.

Install the front shield on the skid plate with the bolts, washers and the locknuts. Do not tighten the locknuts (Figure  9-126).

3.

Secure the front shield to the front crossmember and the intermediate shield with the bolts, washers and the locknuts.

4.

Tighten the locknuts securing the front shield to the skid plate to 24 lb-ft. (33 N•m). Tighten the locknuts securing the front
shield to the crossmember and the intermediate shield to 44 lb-ft. (60 N•m).

.

Figure 9-126:   Driveline Protection Mounting

FRONT SHIELD

FRONT CROSSMEMBER

INTERMEDIATE SHIELD

TRANSFER CASE SHEILD

REAR SHEILD

RIGHT SUPPORT

BRACKET

LEFT SUPPORT 

BRACKET

REAR-FRONT

CROSSMEMBER