the following video was linked on Yuri Pasholok’s blog and I think it’s actually very, very interesting.
The tank you see on it is the Christie M1931. You might remember the name of Walter Christie as the father of the fast BT Soviet tanks and ultimately predecessors to the legendary T-34, which uses a Christie suspension (to be fair, there was a plan to replace the Christie suspension with torsion bars, but the war intervened and nothing came of it).
Christie was known for building not really heavily armored tanks, these were more like race cars with guns and turrets. M1931 Christie tank was for its 10,5 tons powered by a 338hp Liberty engine (32 hp/t!), allowing it to go as fast as 74 km/h on tracks and 113 km/h on wheels (the design could drive around on rubber tyres to speed up the transportation on the road). This however was compensated by very thin armor (16mm at the most) and a short 37mm gun.
In the end, the US Army was interested in heavy, “infantry support” tanks and did not want Christie’s invention. Soviet Union however bought two of these tanks and used them as patterns for the creation of the BT series.