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Nathan Wei Performance

2003 - 2007 LS3 Vortec Standalone Harness Drive by Wire T56 4.8 5.3 6.0 Non Electric

2003 - 2007 LS3 Vortec Standalone Harness Drive by Wire T56 4.8 5.3 6.0 Non Electric

Regular price $389.00 USD
Regular price $435.00 USD Sale price $389.00 USD
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Braided Loom
Extended 1.2m

WARNING: There is no reversal lockout with this harness

For Gen3 2003-2007 Drive By Wire Throttle Body Only

Application: 2003 - 2007 CHEVROLET, GMC, CADILLAC and HUMMER truck engines (drive by wire only) with T56.

Parts Included: Complete Engine and Transmission Harness, Instruction Manual

These harnesses are designed for retrofitting '03 - '07 Vortec engines (4.8, 5.3, 6.0-Liter) and T56. They are completely plug and play with four wire hookup (switched power, constant power and ground connections required). A sliding grommet seal allows for professional, leak proof installation. Harnesses are professionally constructed from Brand New GM Delphi Connectors and TXL (Polyethylene Cross Linked) High Temperature Wire to GM Specifications. All harnesses are 100% Quality Inspected prior to shipping. Note that harnesses are for non-emissions equipped vehicles and do not include air pump or EGR provisions.


  • All of our harnesses are built with OEM Quality and better
  • All Harnesses have a high quality grommet installed on the harness (that slides for desired mounting)
  • Harnesses receive a quality check before shipment.
  • GM color codes. (Many companies do not use GM color codes)
  • High quality reinforced ring terminals
  • 1200 degree fiberglass braid on all circuits ran by heat
  • All factory CPA (Connector Position Assurance Locks)
  • 100% handmade
  • Harness comes with a complete install instruction packet
  • All harnesses come with the needed dash connections, which include Speedometer, Tachometer, Park Neutral, TCC, Malfunction Indicator, and a DLC Port.
  • Upgraded wire for running those big injectors (will run any size injector without issues)
  • 100% Payment Secure
  • Custom Made
  • Free Shipping
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