Upgrading the stereo system in your full-size Chevy or GMC is one of the best bang-for-buck improvements you can make. Factory speakers are paper-thin and the head unit is often years behind modern options. Here’s a complete guide from head unit to speakers to amplifiers.
Step 1: Head Unit Upgrade
The head unit (radio/screen) is the center of the system. Modern aftermarket units offer Apple CarPlay, Android Auto, larger touchscreens, and better sound processing.
For older trucks (pre-2014): The Kissound 7" Double DIN Head Unit with CarPlay & Android Auto is a popular direct-fit option — wireless CarPlay, Bluetooth 5.0, GPS, and backup camera input.
For 2014–2018 K2XX: Use an Android-based 10" unit designed for the factory radio slot (see separate thread in K2XX section).
For 2019+ T1XX: The factory infotainment is more modern but some owners still want full Android replacement units for wireless CarPlay support.
Step 2: Speaker Replacement
Factory speakers are usually 4-ohm, low-power paper cones. Replacing them is one of the biggest audible improvements.
Common locations in GM trucks:
- Front doors (6.5" or 6¾")
- Rear doors or extended cab side panels (6.5" or 6×9")
- Dash/tweeter location on some models
Component vs Coaxial:
- Coaxial (2-way): Easier install, decent sound — good entry-level upgrade
- Component (separated tweeter + woofer): Better staging, better highs — better for enthusiast systems
Step 3: Amplifier
Even a good head unit and speakers benefit from an external amp. Factory head units put out 14–22 watts RMS per channel; an aftermarket amp gives 50–75+ watts RMS per channel.
4-channel amp: Powers front and rear speakers
5-channel amp: Powers speakers + adds a subwoofer channel
Install the amp in the back seat under-seat area or in the cargo area.
Step 4: Subwoofer (Optional)
A 10" or 12" subwoofer in a ported or sealed box fills in the bass that even quality door speakers can’t produce. Popular mount spots:
- Behind the rear seat (enclosed cab)
- Under the rear seat (regular cab)
- Truck bed (sealed box in lockable toolbox for extended cabs)
Wiring Notes
- Run a dedicated power wire from the battery for any amp over 100W
- Use a quality inline fuse within 18" of the battery
- Ground to a clean bolt-down ground on the body — not a convenient screw
- Run signal cables (RCA) opposite the power wire to avoid interference
A well-installed system in a full-size truck can sound genuinely excellent — take your time with the wiring and it’ll last for years.