I believe it is called a brownie, and as I understand there were a variety of them, 2 and 3 speeds. The big truck guys probably know more about them. Probably not too many of them around.
Fred


1956 3100 Pickup/Red/350/3sp OD/PS/Disc Brakes
1957 Bel Air Sport Coupe/Red/355/TH350/PS/Disc Brakes
2017 Silverado LT Single Cab SB/Black/5.3/6 Speed Trans
1947 Willys CJ2A w/F-Head engine