No, a 2001 Chevy truck transmission will almost certainly
not interchange with a 1994 Chevy truck transmission. While both are Chevy trucks, there were significant changes in transmissions over those seven years. The bolt patterns, input shafts, output shafts, and even the overall case design likely differ. The engine and drivetrain configurations also changed significantly from '94 to '01, further reducing the chance of compatibility.
To determine compatibility, you need to know the exact transmission model numbers for both trucks. This information is usually found on a tag attached to the transmission itself. Then, you can research online or consult a parts catalog to see if they are interchangeable. Even then, it's not guaranteed, as there might be subtle differences requiring modifications or making it impractical.
