Th350 Vs. Th400 Transmissions: What're The Differences?

Long earlier automatic transmissions for illustration the 4L60E earned specified bad reputations, General Motors entrusted nan Turbo Hydra-Matic family to grip shifting duties successful its legendary lineup of musculus cars. The first automatic transmissions utilized successful cars were chiefly two-speed affairs for illustration GM's celebrated Powerglide. However, nan TH350 and TH400 automatics upped nan ante pinch an other guardant gear. While nan 2 Turbo Hydra-Matic automatic transmissions shared GM origins and three-speed operation, location are immoderate important differences successful their intended purpose, constituent design, and wide reliability.

Despite nan higher number successful its name, nan TH400 came retired successful 1964, 5 years earlier nan TH350. The TH400 is much heavy-duty, too, featuring stronger components for illustration a 32-spline output shaft while nan TH350 uses a smaller 27-spline version. In banal form, nan TH400 is designed to grip torque inputs up to 450 pound-feet, importantly much than nan 350 pound-feet standing of nan TH350. Overall, nan TH400 was destined pinch durability successful mind to strengthen nan maltreatment of serving successful heavy-duty trucks and high-performance vehicles.

Ultimately, though, nan heavy-duty build of nan TH400 became a disadvantage, and nan lightweight TH350 became celebrated successful accumulation musculus cars of nan era. Today, it's still a bully prime for regular drivers pinch mean motor performance, particularly erstwhile compactness and substance system are prioritized complete durability.

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The history of nan General Motors Turbo Hydra-Matic automatic transmissions goes each nan measurement backmost to a clip erstwhile whale lipid helped cars past earlier modern lubricants took its place. They were derived from nan Oldsmobile-designed four-speed Hydramatic making love backmost to 1939. The Hydramatic's adaptations for usage successful WWII subject vehicles improved its creation while making it much complex, and nan lessons learned from it led to improved designs handed down to nan TH400 and TH350.

The TH350 creation served General Motors good from its precocious 1960s debut, but it was yet replaced by nan 700R4 successful 1982. The TH400 held connected for a while longer, seeing usage successful heavy-duty applications until nan 4L80E replaced it successful 1991. The newer transmission designs featured overdrive, and nan 4L80E successful peculiar besides included physics controls. In time, nan mechanically-controlled 700R4 was replaced by nan 4L60E, different transmission pinch physics controls, successful nan early 1990s.