Look for the 700R4 in a vehicle from 1987 or later, as these units benefited from the most improvements, including the 30-spline input shaft. Transmissions stamped with "K" were found in 4x4 ...

The 700R4, also known as TH700R4, is a General Motors four-speed automatic transmission that was used from 1982 to 1993. Internally called a Hydra-Matic MD-8, it was used in front-engine/rear ...

Retro-fitting modern, overdrive transmissions into early musclecars ... The most popular swaps continue to be the 700R4 and the 200R4, both of which are good choices and have their advantages.