Locking Trans Dipstick B.O.P. TH400

The Locking Trans Dipstick B.O.P. TH400 from Allstar Performance is a precision transmission fluid measurement tool engineered for serious drag racers, transmission builders, and hot rod enthusiasts who demand absolute reliability during high-performance operation. This dipstick is specifically designed for Buick, Oldsmobile, and Pontiac (B.O.P.) vehicles equipped with the legendary TH400 three-speed automatic transmission, addressing a critical gap in transmission diagnostics for vintage muscle car builds and modern restorations.

Accurate transmission fluid level monitoring is non-negotiable when running a TH400 under boost, high RPM, or extended track conditions—even minor fluid loss or overfill can trigger catastrophic transmission failure. The locking mechanism on this dipstick prevents accidental withdrawal during acceleration, cornering, or hard launch—vibration and G-forces can dislodge unsecured dipsticks, leading to fluid spray and inaccurate readings. The tube is precisely calibrated for the TH400's fluid capacity and operating temperature range, ensuring readings remain true whether you're street driving or making full-throttle passes.

At 26 inches in overall length, it accommodates the TH400's typical pan depth and transmission housing geometry without modification. The robust construction and secure locking collar withstand repeated use cycles and the demanding environment of race vehicles while maintaining calibration integrity over years of service. Drag racers and performance enthusiasts will find this dipstick invaluable for ensuring optimal transmission performance and longevity.