Description
Build the replacement system from the factory amplifier connections
Metra 70-2057 72-Inch MOST Amplifier Bypass Harness for Select Chevy and GMC 2014–2017
A 72-inch lead harness for listed GM vehicles equipped with a MOST amplifier.
For 2014–2017 Chevrolet Silverado 1500 and GMC Sierra 1500, and 2015–2017 Silverado 2500 HD/3500 HD and Sierra 2500 HD/3500 HD, the guide specifies an 8-inch factory radio with RPO code IO5 or I06. Check the RPO sticker in the glovebox.
Overview
The Metra 70-2057 connects at the factory amplifier wiring in the listed 2014–2017 Chevrolet and GMC applications with a MOST amplifier. Its black 8-pin and green 16-pin connectors lead into a 72-inch harness for the replacement audio wiring. The installation sheet identifies the speaker circuits and recommends a similar-style aftermarket amplifier to maintain proper operation of all speakers; this harness does not include that amplifier.
Match the factory audio configuration
Confirm the vehicle has the applicable MOST amplifier and use the 70-2057 wiring chart for its black 8-pin and green 16-pin connectors. Center-front Pink/Pink-Black leads are for models with RPO UQS only. The manual identifies dual-voice-coil subwoofer leads when equipped, while the product page warns that factory-subwoofer operation is not retained in select vehicles. Do not assume every speaker or subwoofer configuration is retained by the harness alone; plan an appropriate replacement amplifier and speaker connections.
| Model | 70-2057 |
| Type | GM MOST amplifier bypass harness |
| Harness length | 72 inches |
| Connectors | Black 8-pin and green 16-pin |
| Center-front speaker leads | RPO UQS models only |
| Replacement amplifier | Similar-style aftermarket amplifier recommended; not included |
| Subwoofer | Not retained in select vehicles; conditional connections shown in manual |
Vehicle applications
- 2014-2017 Chevrolet Silverado 1500
- 2015-2017 Chevrolet Silverado 2500
- 2015-2017 Chevrolet Silverado 2500 HD
- 2015-2017 Chevrolet Silverado 3500
- 2015-2017 Chevrolet Silverado 3500 HD
- 2016-2017 Chevrolet Suburban 3500 HD
- 2014-2017 GMC Sierra 1500
- 2015-2017 GMC Sierra 2500 HD
- 2015-2017 GMC Sierra 3500 HD
Use only the listed vehicles with the applicable MOST amplifier. A similar-style aftermarket amplifier is recommended and sold separately. Factory-subwoofer operation is not retained in select vehicles; follow the configuration-specific wiring chart.