TH400 Deep Aluminum Pan

The TH400 Deep Aluminum Pan from Transmission Specialties is engineered for serious transmission builders and performance enthusiasts who demand maximum fluid capacity and superior heat dissipation. This deep sump pan is designed to replace the factory pan on TH400 transmissions, allowing you to run significantly more transmission fluid while improving thermal management during extended driving or heavy towing. Whether you're building a street machine, daily driver, or competition vehicle, this pan addresses one of the most critical cooling challenges in automatic transmission longevity.

Constructed from lightweight aluminum, the TH400 Deep Aluminum Pan features a finned design that increases surface area for enhanced heat rejection—critical for maintaining optimal fluid viscosity and transmission durability under sustained load. The deep sump configuration holds approximately 4–6 additional quarts compared to the OEM shallow pan, giving you greater thermal mass and allowing temperature to stabilize during highway cruising or drag strip launches. The natural aluminum finish resists corrosion while maintaining clean aesthetics in engine bays, and the pan's robust construction ensures it withstands mounting stress and road debris without flexing or developing leaks.

This pan is ideal for street and strip builders running modified TH400 transmissions in hot rods, muscle cars, trucks, and performance restorations where transmission temperature control directly impacts reliability and shift quality. Installation requires standard pan removal and gasket replacement; proper torque sequencing and a fresh gasket seal are essential to prevent leaks. The TH400 Deep Aluminum Pan is a must-have upgrade for anyone serious about transmission longevity, especially in builds where higher stall converters, aggressive gearing, or sustained performance driving would otherwise push fluid temperatures into the red zone.