GM radios run the gamut from very basic to quite capable. You can get a system equipped with everything from MP3 capability to GPS DVD navigation. Car stereo enthusiasts want the kind of power and range that can only be delivered by a stereo system that includes a subwoofer. The bass is what delivers the full range of sound and makes for a truly complete audio system. Adding a subwoofer to a stock GM radio requires that you first add an amplifier or, as this article will describe, install a powered subwoofer.
Remove the grounding cable from the negative battery lead of the GM vehicle. The grounding cable is connected to the negative battery lead (marked with a minus sign or "NEG") and runs to a point on the frame of the vehicle. Use a Phillips-head screwdriver to remove the cable from the negative lead post.
Connect the power supply cable from the amplifier wiring kit to the positive battery lead.
Run the power supply cable from the engine compartment into the inside of the vehicle, through the firewall. The cable will emerge in the foot well on the driver's side.
Remove the stereo from the dash of the vehicle. Removing the stereo requires that you remove the dash trim panel surrounding the radio. Use a Phillips-head screwdriver to remove the screw in the dash panel just to the right and below the steering column. Pull the dash panel free from the vehicle.
Remove the bolt screws on either side of the stereo mounting bracket. The screws can be removed with a 7-millimeter socket and ratchet or a Phillips-head screwdriver. Pull the stereo from the dash.
Remove the wiring connections to the rear of the stereo by pulling the wiring from the radio. Connect the wiring to a wiring harness adapter. Connect the wiring harness leads to the stereo.
Connect the signal cable and turn-on lead from the amp wiring kit to the wiring harness adapter. Feed the cables through the rear of the stereo mounting dock and down to the foot well of the passenger side of the vehicle.
Replace the stereo into the dash of the vehicle. Replace the two 7-millimeter bolts on either side of the radio. Replace the dash trim panel and screw in the screw on the lower section of the dash near the steering column.
Remove the trim panels along the doorways of the vehicle with the trim panel removal tool. Lift the carpeting on either side of the vehicle to lay the cables to be routed to the rear of the vehicle.
Run the power supply cable (from the battery) along the driver's side of the vehicle, beneath the carpet, to the rear cargo area of the GM car, truck or SUV. Lay the signal cable and turn-on lead (from the passenger-side foot well) along the passenger side of the vehicle.
Replace the carpeting and secure the trim panels at the doorways by hand. Pressing the panels in place will fasten them to the floor of the vehicle.
Connect the signal cable, the turn-on lead and the power supply cable to the subwoofer in the rear of the vehicle. Connect the grounding wire (from the amplifier wiring kit) to the subwoofer and then to a screw or bolt in the rear of the car. The purpose of the grounding wire is to ground the system and any bolt connected to the frame of the vehicle will work fine.
Reconnect the grounding cable to the negative battery lead post. Tighten the cable on the post with a Phillips-head screwdriver.
