TH400 (Reid Case) Transmission Selector Position Kit

Ultimate Drivetrain Feedback: TH400 (Reid Case) Selector Position Kit

In high-power drag racing where the TH400 Reid Case is used for its SFI-certified strength, standard transmission accessories often fail to fit correctly. The TH400 (Reid Case) Transmission Selector Position Kit is a purpose-built solution designed to integrate the industry’s toughest transmission with professional standalone ECU integration. By utilizing a 50mm linear position sensor, this kit provides a 0-5V analogue signal that accurately identifies the selected gear. This level of feedback is vital for builders of 2JZ and LS-swap drag cars who require precise traction control and gear-based boost strategies to maintain dominance on the strip.

Engineering Principles: Precision Linear Feedback

The Reid Case is physically larger and has different mounting bosses than a standard GM TH400 case. This kit includes a custom-designed bracket specifically to suit TH400 Reid Case transmissions. The heart of the system is the HT-011201 Linear Position Sensor, which provides millisecond-perfect resolution of the selector’s travel. This Analogue-to-Digital interface allows the tuner to assign precise voltage values to P, R, N, 1, 2, and 3. This is foundational for harness integration in competitive motorsport, as it ensures the ECU knows exactly which gear is engaged, allowing for the execution of complex fuel map calibrations that account for varying drivetrain inertia.

Operational Benefits: Traction and Safety Strategy

Integrating gear position data into a Haltech Nexus or Elite series ECU enables high-tier Boost-by-Gear logic. With closed-loop boost control, the tuner can program the ECU to limit boost in low gears where traction is limited and maximize it in high gear. Additionally, this kit provides the data necessary for Starter Motor Lockout and Reverse Light Activation, which are critical for passing technical inspections and ensuring vehicle safety. For engines utilizing anti-lag or launch control, this kit ensures that these aggressive strategies are automatically disabled as soon as a gear change is detected, acting as a secondary layer of detonation protection.

Fitment and Software Integration

This kit is specifically engineered for the Reid Racing version of the TH400. It integrates seamlessly with Haltech’s NSP and ESP software, as well as the iC-7 Digital Display, giving the driver a clear gear indicator on the dash. The sensor features an IP65 rating, ensuring it survives the heat and grime of an under-car environment. The kit includes the custom mounting bracket, the linear sensor, and nylon mounting hardware to prevent electrical grounding issues. This is a mandatory component for any professional drag build utilizing the Reid case for absolute drivetrain integrity.

Technical Specifications

Summary & Includes

The TH400 Reid Case Selector Kit is the essential bridge between heavy-duty mechanics and digital control. Includes: 1 x Reid Case Mounting Bracket, 2 x 5/16 x 1/2″ Bolts, 2 x #8-32 Nylon Bolts/Nuts, and 1 x HT-011201 Linear Position Sensor. Note: Specifically designed for Reid Racing cases; will not fit standard GM TH400 cases.