When it comes to installing door speakers in your 2003 Silverado, you are limited to certain sizes due to the design of the doors. The front-door speakers are technically 6 1/4-inch speakers. The rear-door speakers, on four-door models, are a bit smaller but are assembled into a 4-by-6-inch bracket. You can install any 6 1/2-inch speaker in the front doors. For the rear doors, you can install a replacement stock speaker, or you can perform some custom work and install a shallow 6 1/2-inch speaker. The aftermarket speakers you choose for the rear doors must not exceed a mounting depth of 1 3/4-inches.
There is a lot of confusion in relation to the audio system on the 2003 to 2007 Silverado. Most information available is based on years outside of this time frame and does not apply to your 2003 Silverado. If you are ever in doubt, refer to the service manual for your vehicle. You can buy a year-specific service manual in paperback or digital form from various retailers online as well as from your local Chevy dealer.
Pull outward on the door handle, then pry the bezel out of the door trim with a trim-removal tool or a flathead screwdriver. Pry the upper extension panel -- the triangular piece opposite the mirror -- off of the door. Pry the manual door lock away from the door trim. Remove the screw that was hidden behind the manual door-lock lever, the screw in the opening of the armrest and the screw beneath the bottom pocket. Slide the panel upward, then pull it away from the door. Disconnect the wiring harnesses from the switches on the panel, then set the panel aside.
Remove the speaker screws from the door. Pull the speaker outward and disconnect the wiring harness from the speaker. Discard the speaker.
Connect the wiring harness to a new 6 1/2-inch speaker. Guide the speaker into the mounting hole. Secure the speaker with the included ½-inch self-taping screws, using a drill.
If the stock wiring harness doesn't fit on the connectors of the new speaker, cut the stock connector off the speaker wire. Install a small blade connector on each wire, then connect the wires to the speaker.
Connect the wiring harnesses to the switches in the door’s trim panel. Align the plastic retainers on the back of the panel with the holes in the door. Press the panel against the door, then slide it downward to secure it. Install the mounting screws and snug them. Press-fit the upper extension panel, manual lock lever and handle bezel to the trim panel. Repeat this entire process for the opposite front door.
Pull out on the door handle, then pry the small bezel out of the trim panel with a flathead screwdriver or trim-removal tool. Pry the manual door-lock lever from the trim panel. Remove the screw below the speaker grill, and the screw hidden by the manual lock lever. Slide the panel upward then pull the panel away from the door gently. Disconnect the wiring harnesses from the switches in the trim panel, then set the panel aside.
Remove the three speaker screws from the speaker bracket. Remove the speaker from the bracket, then disconnect the wiring harness. If you are installing a shallow mount, 6 1/2-inch speaker, remove the three bolts that secure the bracket to the door. Remove the bracket.
File down the edges around the opening until a shallow mount, 6 1/2-inch speaker fits snugly in the bracket. Mount the new shallow-mount speaker into the bracket and secure it in place with the included self-taping screws.
A non-shallow mount speaker may appear to fit in the door correctly, but when the window is lowered it will strike the magnet on the back of the speaker. This may damage the glass, window regulator or speaker.
Attach the wiring harness to the new speaker. Hold the bracket against the door and align the three mounting holes. Install the screws and snug them.
Attach the wiring harnesses to the switches in the panel. Align the tabs on the back of the panel with the holes in the door. Press the panel into place, then tap it downward to secure it. Install the two screws and snug them. Press-fit the manual door lock and handle bezel into the trim panel.
