• Metra 40-GM18 Reverse Antenna Adapter for Select GM Vehicles 1988-2013
  • Metra 40-GM18 Reverse Antenna Adapter for Select GM Vehicles 1988-2013 - product image 2
  • Metra 40-GM18 Reverse Antenna Adapter for Select GM Vehicles 1988-2013 - product image 3
  • Metra 40-GM18 Reverse Antenna Adapter for Select GM Vehicles 1988-2013 - product image 4
  • Metra 40-GM18 Reverse Antenna Adapter for Select GM Vehicles 1988-2013 - product image 5
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Metra

Metra 40-GM18 Reverse Antenna Adapter for Select GM Vehicles 1988-2013

Metra 40-GM18 Reverse Antenna Adapter for Select GM Vehicles 1988-2013

$23.99 USD
$23.99 USD
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Before you order

Buy with the right details confirmed

Review the application and system requirements

Confirm the size, power, connections, and included or separately required parts described on this page.

The Metra 40-GM18 Antenna Adapter is designed for select General Motors and related vehicles. It provides the correct antenna connection when using an aftermarket antenna with the original factory radio.

At a Glance

  • Vehicle antenna adapter for select General Motors and related vehicles
  • Supports using an aftermarket antenna with the original factory radio
  • Aftermarket antenna to GM factory radio antenna cable
  • Helps maintain the AM/FM antenna connection during radio, antenna, or FM-modulator integration
  • Designed to avoid cutting factory antenna wiring when matched to the correct vehicle and radio configuration

System / Fitment Notes

  • Reverse antenna adapter for retaining the factory radio while changing the antenna side of the connection

Vehicle Compatibility

Make Model Years
Buick Select GM-platform models 1988-2013
Cadillac Select GM-platform models 1987-2006
Chevrolet Select GM cars, trucks, vans, and SUVs 1984-2011
GMC Select trucks, vans, and SUVs 1985-2009
Hummer H2 / H3 / H3T 2003-2010
Hyundai Santa Fe 2003-2006
Isuzu Ascender / Hombre 1998-2008
Oldsmobile Select GM-platform models 1983-2004
Pontiac Select GM-platform models 1986-2008
Saturn Select models 1991-1999
Toyota Matrix 2003-2008

Installation Notes

  • Confirm exact year, make, model, factory radio, antenna connector style, and radio being installed before installation
  • Test-fit the antenna adapter and review manufacturer instructions before final assembly
  • Additional dash kits, wiring harnesses, steering wheel control interfaces, or factory feature-retention parts may be required
  • Professional installation is recommended for best results

What’s in the Box

  • Antenna adapter cable

Technical Specifications

  • Brand: Metra
  • Model: 40-GM18
  • Product Type: Antenna adapter
  • Application: Vehicle antenna integration
  • Connector Type: Aftermarket antenna to GM factory radio antenna cable

Identifiers & Packaging

  • MPN: 40-GM18
  • UPC: 086429019601
  • Sold As: Each
  • Included Components: Antenna adapter cable

Why Buy From MCOR Automotive

  • Authorized retailer for the brands we sell
  • Specialists in vehicle audio integration, radio replacement parts, and installation accessories
  • 22+ years of professional automotive electronics experience
  • Expert support for compatibility verification and proper setup
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