I agree with Wrenchbender, I have a 700R4 behind a zz4 350 with over 400ft. pounds of torque, runs great. Reduced the rpm's on the highway alot. Running 373 gears. Made the same switch in the 72 Nova we owned, same results. Would never go back to the th350 or 400. Worth the extra bucks. Gas mileage did improve, but more importantly the rpm's were reduced , less engine wear. Just my thoughts, has been a good move for me.

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53 half ton http://s159.photobucket.com/user/sworden73/library/?sort=3&start=all&page=1
72 Nova SS sold
75 Corvette
52 Chevy Styleline Coupe