There were no injuries reported, but southbound traffic on the interstate was backed up or miles. California Highway Patrol officers shut down three lanes near Templin Highway, leaving only two open.
CHP officials said that a big rig hit another rig and soon erupted in flames. The blaze spread to a nearby bush. The cab was quickly enveloped in flames that spread to the refrigerated trailer, which was believed to be hauling eggs.
The fire was extinguished in about a half-hour but freeway lanes were expected to be shut down until 8 a.m.
AP contributed to this report.