Not the T24E1. It carried a very unusual weapon for a US vehicle the final product had a much more "mainstream" gun.
Not a T20E3, think smaller. BTW I have the T20E3 mounting a 76mm, so a US gun , not a "77mm" that was usually used to identify the "short recoil" derivative of the British 17lb, did some mount it?. The gun on this tank was of British origin, but not the 17lb or one of it's derivatives.
How about the T49 In the early 1940's America wanted a tank destroyer force so they tested the 57mm gun in a new vehicle, The weapon had a muzzle velocity of 2700+ feet per second, The range was about 2.5 miles, The vehicle was powered by two Buick engines and could reach speeds up to 50 mph
T49 Gun Motor Carriage is correct, AFAIK one of the few US vehicles to carry the 6lb AT gun, the vehicle eventually evolved into the M18 Hellcat. Your go
Deep down it looks like it's a T34, a bit unfair to post the worl's most produced tank and expect us not to recognize it Sa that very picture recentlly, I remember something like "concrete tank" ... must be getting old.
I'll give you that as that's about the same info I have except it was a prototype with a concrete suit on so the vehicle could be used as a pill box, Similar idea to the British concrete lorry Your go