For 1990-2009 cars only
Removal Procedure
- Discharge the air pressure from the air brake system. Refer to Draining Reservoirs in Air Brakes.
- Remove the lanyard bolt from the inner roof panel.
- Remove the left rear quarter trim panel (models with headliner). Refer to Headlining Trim Panel Replacement in Interior Trim.
- Remove the air horn opening trim cover, if used.
- Remove the air horn air tube from the air horn valve.
- Tape the air horn air tube to the roof in order to help prevent the air line from recoiling back into the roof panel.
- Remove the air horn front mounting bracket.
- Remove the air horn mounting bolts.
- Remove the air horn assembly from the roof.
- Remove the tape from the air horn tube roof.
Installation Procedure
- Connect the air horn tube to the air horns.
- Route the lanyard through the roof into the cab.
- Install the air horn assembly to the roof.
- Install the air horn front mounting bracket.
- Install the air horn mounting bolts.
- For models with headliner, install the left rear quarter trim panel. Refer to Headlining Trim Panel Replacement in Interior Trim.
- Install the lanyard bolt to the inner roof panel.
Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.
Tighten
Tighten the air horn mounting bolt to 9 N·m
(80 lb in).
Tighten
Tighten the lanyard bolt to 2 N·m (18 lb in).
