For 1956 the light-duty R-series evolved into the S-series. The cab was unchanged but the front end was restyled. The horizontal bar of the old grille was replaced by an oval ring inside a larger trapezoidal opening and the parking lights were mounted on the ring. The headlights were moved to the top front of the fenders where they protruded slightly from the now forward-leaning fenders. The S-100 series came in the basic S-100 model, with unchanged 4,200 lb GVW, and the S-102, with the GVW up to 5,000 lb. Standard equipment in both models was the 108-hp Black Diamond BD-220 engine (a renamed Silver Diamond SD-220) and 3-speed syncromesh transmission. The 131-hp Black Diamond BD-240 was optional for the first time in the 100-series. Optional transmissions were a 3-speed with overdrive or a