New regulations were enacted for 2015, requiring an 80-percent redesign of the TS040; this included a new front-end crash structure, a suspension optimised to preserve tyre life and additional weight reduction. Two body kits were designed: one for fast tracks and the other for tight turns. Designers added a guide vane below the car's headlights for balance while braking, but felt that a second (at the rear of the vehicle) would create turbulence. Little work was conducted on the powertrain. Although Toyota considered changing to a battery system, comparing its hybrid technology with that installed in the Porsche 919 Hybrid and switching to the category, the manufacturer ultimately decided to remain in the class. However, the TS040's supercapacitor was modified for enhanced performance. Construction of the car began immediately after the 2014 24 Hours of Le Mans, and continued until January 2015.