Adding Rock Lights for 1999 GMC Sierra 1500 Off-Road Illumination apsense.com bookmark
Run the main harness along the frame rail, following existing factory lines and securing with zip ties every 12 inches. Route the switch wire through a firewall grommet—typically located near the steering column—into the cabin. Mount your rock light switch in an unused dash blank or in a discreet location below the dashboard. Connect the harness power leads to the battery (positive to positive, negative…
Installing Sequential Turn Signals in the 1999 GMC Sierra 1500 Taillights morsunled.wordpress.com bookmark
Installation requires only basic hand tools and about 30 to 45 minutes. Begin by lowering the tailgate to access the two retaining screws securing each taillight housing—one upper and one lower . Use a Phillips screwdriver to remove these screws, then gently pull the taillight assembly straight out from the truck body. Be careful not to force it, as the factory harness is still connected….
DOT Approved 1999 GMC Sierra LED Headlights Upgrade luxevolume.com bookmark
Alternatively, LED replacement bulbs designed to fit the factory 9005 (high beam) and 9006 (low beam) sockets are available. However, a significant legal caveat applies: LED conversion bulbs installed in original reflector housings are not DOT-legal for on-road use in many jurisdictions . The reflector housing is optically engineered for halogen filaments, which emit light 360 degrees, while LED chips produce directional light. Even with…
Upgrading the 1999 GMC Sierra 1500 Cargo Light to LED atoallinks.com bookmark
Insert the new LED bulb. Note that LEDs are polarity-sensitive; if the light does not illuminate when you test it, simply remove the bulb, rotate it 180 degrees, and reinsert. Reattach the lens cover, ensuring all clips snap securely into place. Test the cargo light using the dash-mounted switch or by opening a door (the cargo light often activates with the dome light circuit). The…
Installing Fog Lights on a Base Model 1999 GMC Sierra 1500 storeboard.com bookmark
Before installing any auxiliary lighting, however, you must address the condition of your truck’s factory headlights. On a 1999 GMC Sierra 1500, the original composite headlight lenses are now over 25 years old. Prolonged exposure to UV radiation, road salts, and temperature extremes causes the polycarbonate plastic to oxidize, turning from clear to a hazy, yellowed, and scratched surface. Driving a base model Sierra with…
Installing Fog Lights on a Base Model 1999 GMC Sierra 1500 graph.org bookmark
To begin the fog light installation, choose a kit designed for GMT400-platform trucks (1999 was a transition year, but the Sierra classic body style shares components with late 1990s models). Universal LED fog light kits with a 3- to 4-inch round or rectangular housing work well. You will also need a wiring harness with a relay, fuse, switch, and sufficient 14-gauge wire. Start by removing…