* Overall Size and Strength: The TH400 is significantly larger and stronger than the TH350. It's designed for heavier-duty applications and higher torque output. The TH350 is more compact and lighter.
* Torque Capacity: The TH400 can handle considerably more torque than the TH350. This makes it better suited for powerful engines, trucks, and performance applications.
* Number of Gears: Both transmissions are three-speed automatics.
* Gear Ratios: While both have three forward gears, the gear ratios differ slightly between the TH350 and TH400, impacting acceleration and cruising characteristics. The TH400 generally has lower gearing for more aggressive acceleration.
* Construction: The TH400 has a more robust internal construction, with heavier-duty components throughout. This contributes to its greater durability and higher torque capacity.
* Serviceability: The TH400, being more complex, can be more expensive and time-consuming to repair or rebuild.
* Applications: The TH350 was used in a wide range of GM passenger cars and some light trucks, while the TH400 was prevalent in larger, more powerful cars, trucks, and some performance vehicles.
In short: There's no TH375. If you're comparing a TH350 to a TH400, the TH400 is the bigger, stronger, heavier-duty transmission for higher torque applications. The TH350 is smaller, lighter, and more economical for less demanding uses.
