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Used 125C Transmission

22 years of production by General Motors was placed into the TH125 transmission assembly. This 3-speed gearbox was first developed and marketed in the 1980 year and is sometimes referred to as the 3T40. Nearly all body styles of vehicles were adapted to fit the 125 series gearbox during its production run. Purchasing a used 125C transmission for sale has never been so easy using this auto parts website online.

Difference Between TH125 and 125C Gearboxes

While the majority of the design was the same, what was really different is the fact that a torque converter clutch was added in the c-series. This is why the designation of 125C was used. An electronic pulse is used in conjunction with a solenoid to active the clutch system. The regular TH gearbox did not feature this design in any of its original or updated builds.

General Motors did introduce a heavy-duty transmission that was based on the 125C in the U.S. The 1988 year marked the short live span of the AWD edition. A special planetary gearing system was used to transfer more of the total power to the the remaining three vehicle wheels. A time period of only 24 months was used to exploit this model to the public before it was discontinued.

125C GM Transmission Problems

There is a known flaw in many of the original c-series transmissions produced in the 1980s. The solenoid can burn out making the shifting pattern unreliable. The gear ratio of 2.84, 1.60 and 1.0 is standard on all 125C units although the clutch system depends on the solenoid. This problem is an easy fix through most dealerships and mechanics working on GM cars.

Some owners of the 125C transmission from GM have also reported issues with the throttle pressure cable. This is one issue that can lead to irregular shifting during use. Some people have complained that the c-gearbox shifts either too late or too soon in 2 of the 3 gears. The lock up solenoid has also been reported to fail. All PreownedTransmissions.com inventory offered here has been validated for quality and craftsmanship.

Where to Buy Used 125C 3-Speed Transmissions

By taking less than a minute to review pricing on this page, a person can learn just how cheap a classic transmission can be to buy. A sophisticated inventory finder is now part of the 21st century tools that appear here to car parts buyers, mechanics or body shop owners who need to find a used turbo-hydramatic transmission for sale.