Sales of V-6 engines with F-150 pickup trucks this year have surpassed V-8 engines at a level not seen since the late 1960s, according to the Ford Motor Co.

More than 57 percent of retail sales of F-150 trucks have come with the V-6 creating the highest V-6 mix in the industry since 1967, according to Ford.

In the past three years, V-6 engine growth in light-duty pickups has exceeded 600 percent with the F-150 accounting for 91 percent of that growth. In 2013, Ford accounted for 78 percent of V-6 half-ton pickup sales, according to the automaker, who cited registration data provided by Polk/IHS.

"We expect those numbers to hold for the rest of the year," said Doug Scott, Ford Truck marketing manager. "It really is amazing when you consider we are doing that with just two V-6 engine choices – the 3.5-liter V-6 Ecoboost and the 3.7-liter Ti-VCT V6 engine. When we come out with the new 2015 F-150, we will offer three different V-6 engines, so the potential is there to go even higher."

The 2015 F-150 will add a third option — a new 2.7L Ecoboost V-6.