Installing an amplifier in a GMT900 Silverado/Sierra is straightforward but requires careful planning. Here’s the complete guide.
Planning the Install
Before purchasing an amp, determine:
- How many channels do you need? (2-ch for sub, 4-ch for speakers + sub)
- Where will you mount it?
- What gauge power wire do you need?
Power Wire Gauge:
| Amp RMS | Fuse Size | Wire Gauge |
|---|---|---|
| Under 200W | 40A | 8 AWG |
| 200-400W | 60A | 6 AWG |
| 400-750W | 80A | 4 AWG |
Running Power Wire to GMT900:
The power wire from the battery runs through the firewall. The GMT900 has a grommet pass-through on the driver side firewall — use a coat hanger to guide the wire through.
Run the wire under the door sills (remove the sill panels) to the amp location. Use split-loom wrap to protect the wire.
Signal Wire:
The signal (RCA) wire runs from the head unit preamp outputs to the amp. The Kissound 7" Double DIN has 2V preamp outputs that work well with most amps.
Ground:
The ground wire goes to bare metal, preferably the floor pan bolt near the amp location. Scrape paint to get a solid metal connection.
GMT900 Factory Amp:
If your truck has the Bose system, you may need to tap the factory speaker wires at the speakers (not the head unit) to maintain proper impedance.