I was driving south on I-5 just south of Stockton CA. About 7pm, I witnessed 6 bright orange orbs directly in front of me that were in the shape of a diamond. They illuminated a steady reddish orange glow. I thought they may be several helicopters at first. The formation abruptly changed pattern as 4 of the orbs formed a semi-circle to the upper right of the formation and 2 fell down and to the left in a straight line above and parallel to the horizon. The formation flew directly over me, and judging by the speed and cloud cover backdrop they appeared to be small and close to the ground. I wished I could pull over to see if I could hear anything. Being former Marine, I had not seen any aircraft that had running lights such as these. There were no flashing strobes or other type of standard running lights that I could see. I was able to see the objects in my mirrors as I continued to drive and lost sight of them after a short time.