He received an Academy Award for Best Original Screenplay nomination as one of the writers of Toy Story (1995), and was also co-director on Cars (2006), his final work.
On August 16, 2005, Ranft and his friend Eric Frierson were passengers in Ranft's 2004 Honda Element, which was being driven by another friend, Elegba Earl. Earl suddenly lost control and crashed through a guard rail while northbound on Highway 1. The SUV plunged 130 feet into the mouth of the Navarro River in Mendocino County, California. Ranft and Earl were both killed instantly. Frierson survived by escaping through the sun roof, though he received moderate injuries. Ranft, who was 45, died during the production of Cars, which he co-directed and voice acted in.