The Stanislaus County Coroner’s Office has identified the 52-year-old male involved in the fatal collision just outside of Turlock on Monday afternoon.
Gary Wallace Arnebeck, 52, of Modesto, was killed after colliding with a boulder and tree at the T-intersection of Tuolumne and Gratton roads.
California Highway Patrol responded shortly before 2 p.m. on Monday after receiving report of the collision.
Emergency crews declared Arnebeck deceased at the scene.
Authorities said Arnebeck was traveling eastbound on Tuolumne Road at a high-rate of speed when he ran the stop sign and collided head-on with the tree and boulder.
Witnesses told CHP that Arnebeck did not touch the brakes as he approached the intersection.
Authorities are investigating whether Arnebeck had a medical condition or emergency prior to the collision. The collision is currently under investigation.