Chevrolet Silverado / GMC Sierra. Service manual — part 2773

SUNROOF DRAIN INSPECTION AND CLEANING

Drain Hose Routing

A drain trough encircles the sunroof window panel and water is drained off by the drain hoses
located at each corner of the housing. A drain channel spans across the sunroof module at the rear
of the window panel and directs water into the trough.

1. The front drain hoses are routed down the windshield pillars and out the center of the pillar

between the door hinges. The front hoses are installed in a rubber grommet and retained by
clips.

2. The rear drain hoses are routed through the rear pillars and out of the rocker panel. In some

vehicle the drain hoses are routed out through the metal roof slots and routed to the lower
wheelhouse to drain out of the vehicle. The rear hoses are installed in a rubber grommet and
retained by clips.

Plugged Drain Hose

If a waterleak has occurred check for a plugged drain hose at each corner of drainage system.

1. Open the sunroof window.

2. To test for blockage, pour a small container of water into the module housing drain trough.

Check each corner to confirm the drain hose is draining water.

3. Use compressed air, 241 kPa (35 psi) or less to blow out any drain hose that is plugged.

1. Open the sunroof to expose the 2 rivets located on each side.

2. Tape off the under side of the sunroof track when drilling to prevent

debris from entering the track.

3. Drill out the rivets.

2

Sunroof Air Deflector
Procedure:
Before cycling the sunroof, vacuum out the sunroof track to remove all debris.

IMPORTANT: If the headliner is wet DO NOT remove any interior trim. Do the

Plugged Drain Hose test first.

CAUTION: Wear safety glasses in order to avoid eye damage.

2008 Chevrolet Silverado 1500

2008 ACCESSORIES & EQUIPMENT Sunroof - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra & Silverado

4. Test the system again.

5. If the hose remains plugged, check to see it is properly routed and does not have a kink.

Refer to Sunroof Housing Front Drain Hose Replacement or Sunroof Housing Rear
Drain Hose Replacement.

6. Remove the blockage using the following steps.

1. Push mechanics wire through the hose to remove the obstruction.

2. Use compressed air in order to blow out any remaining material.

Disconnected Drain Hose

Inspect the drainage system for disconnected drain hoses. Complete the following steps in order
to obtain partial access to drain hoses and check for a disconnected hose.

1. Open the sunroof window panel.

2. Lower the headliner as needed. Refer to Headlining Trim Panel Replacement (Regular

Cab) or Headlining Trim Panel Replacement (Crew Cab) or Headlining Trim Panel
Replacement (Extended Cab) .

3. Connect any disconnected hoses.

4. Ensure that the rear drain hoses are properly routed in the metal roof slot and taped in place.

SUNROOF WATER GUTTER REPLACEMENT (EXTENDED CAB)

Removal Procedure

1. Remove the air deflector. Refer to Sunroof Air Deflector Replacement (Extended Cab)

or Sunroof Air Deflector Replacement (Crew Cab).

2. Set the sunroof window to be in the open position of a minimum of 25 mm (1 in).

3. Remove the sunroof module assembly. Refer Sunroof Module Assembly Replacement.

IMPORTANT: Tape off the perimeter of the sunroof window opening before

removing the sunroof module to prevent scratching.

IMPORTANT: It is only necessary to lower the headlinder. Only do those

steps in headlinder replacement that will lower the
headlinder enough to grain access.

2008 Chevrolet Silverado 1500

2008 ACCESSORIES & EQUIPMENT Sunroof - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra & Silverado

Fig. 7: Screws And Water Gutter
Courtesy of GENERAL MOTORS CORP.

4. Remove the screws (1) from the water gutter (2).

2008 Chevrolet Silverado 1500

2008 ACCESSORIES & EQUIPMENT Sunroof - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra & Silverado

Fig. 8: Water Gutter & Retainers
Courtesy of GENERAL MOTORS CORP.

5. Slide the water gutter rearward to release the retaining tabs (1) from the slots (2) in the

track.

6. Remove the water gutter (3) from the track.

Installation Procedure

2008 Chevrolet Silverado 1500

2008 ACCESSORIES & EQUIPMENT Sunroof - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra & Silverado