Speedmaster Turbo 400 TH400 TH375 M40 Transmission Shift Improver Kit - Stage 2

The Speedmaster Turbo 400 TH400 TH375 M40 Transmission Shift Improver Kit – Stage 2 (PCE222.1007) is engineered to enhance shift quality and responsiveness in compatible Turbo 400-series automatic transmissions. This Stage 2 kit is designed to modify shift characteristics, providing smoother and more controlled gear transitions during acceleration and deceleration.

This transmission shift improver kit fits Turbo 400, TH400, TH375, and M40 transmissions, making it suitable for classic muscle cars, street rods, and performance builds that rely on these proven automatic gearboxes. The Stage 2 configuration offers a balanced approach to transmission tuning, ideal for builders seeking noticeable shift improvement without extreme modifications. Installation requires mechanical knowledge and access to transmission service tools, and is best performed by experienced transmission technicians or qualified shops.

Key Features & Benefits

• Fits TH400 Series: Compatible with Turbo 400, TH400, TH375, and M40 automatic transmissions.
• Stage 2 Tuning: Designed to enhance shift quality and responsiveness in compatible transmissions.
• Improved Shift Control: Provides smoother gear transitions and better shift feel during acceleration.
• Performance Focused: Ideal for hot rods, classic cars, and street performance builds.

Specifications

Ideal Applications

• Classic muscle car and hot rod transmission tuning
• Street performance automatic transmission upgrades
• Improved shift feel and response in vintage automatic-equipped vehicles
• Transmission modification for enthusiasts seeking smoother gear transitions