Reuel De Villa, of Cerritos, was changing a tire on his Volkswagen Jetta along the westbound 105 Freeway near Garfield Avenue around 4 a.m. when he was struck by a 2007 Toyota Tunda.
The force of the impact reportedly tossed De Villa into the air.
According to authorities, the male suspect stopped his pickup truck but ran away on foot in an unknown direction.
De Villa was pronounced dead at the scene.
The freeway ramps were closed for three hours for the death investigation, according to the CHP.
Anyone with information regarding the hit-and-run was asked to contact the California Highway Patrol at (323) 980-4600.
CNS contributed to this report.