Speartech STE-LS3-T56M LS3 Crate Powertrain Swap Controls Kit T56 Magnum

The Speartech STE-LS3-T56M is a complete LS3 Crate Powertrain Swap Controls Kit designed specifically for use with the T56 Magnum manual transmission. Built to order by Speartech — a specialist in LS and LT engine swap wiring solutions — this kit delivers a true plug-and-play powertrain control solution for LS swap builds that demand factory-level integration.

This kit pairs a custom-built main engine harness with a dedicated transmission harness, a pre-programmed ECU, and all supporting emissions and sensor components needed to get your LS3-powered swap running properly. Every wire is labeled for straightforward installation, and an integrated OBD2 port with check engine light output makes future diagnostics simple.

Kit Includes:

• Custom-built Engine Main Harness (plug-and-play with all engine and emissions sensors)
• Transmission Main Harness (T56 Magnum compatible)
• Engine ECU (pre-programmed for LS3)
• Transmission Control Module (TCM)
• EVAP Canister
• Pre- and Post-Cat Oxygen Sensors
• Drive-By-Wire (DBW) Throttle Pedal
• Compatible MAF Sensor with Aluminum Weld-On Bung
• Fuel Tank Pressure Sensor
• 6AN Inline Fuel Pressure Sensor
• 4-Pin Fuel Rail Pressure Sensor and Fuel Pump Control Module (FPCM)
• OBD2 Port with Integrated Check Engine Light Output
• Full installation instructions with labeled wiring throughout

Key Features:

• Built to order — each harness is custom-made for your specific application
• Supports all factory emissions control devices required for your LS swap
• Compatible with Gen 4 LS engines including LS3, L99, LS7, LSA, LS9, and 5.3/6.0/6.2 Vortec truck variants
• T56 Magnum transmission harness and TCM included
• Every wire labeled for clean, professional installation
• Integrated OBD2 port for easy diagnostics

Speartech is a recognized leader in LS and LT swap wiring harness solutions, offering support for Gen 3, 4, and 5 LS/LT engines. The STE-LS3-T56M takes the guesswork out of engine swap wiring by providing everything needed in a single, cohesive controls package.