We were driving north on hey 99 and like every night, there was air traffic. i saw a larger than normal light off in the distance, maybe a few miles. after about 30 seconds of watching while still driving, the one light suddenly becomes three lights, in a horizontal pattern. i pulled over to the side of the road and my friend and i continued to watch as this object got closer, yet still high up in the sky. right as the lights got right over my truck, the three lights became 4 light and were now in the shape of a diamond. i turned my camera on and gave it to my friend so he could try to film the craft. as it got right over top of the truck it made a sharpe right turn and seemed to glide off to the east. the craziest thing about it is how quiet the craft was. we couldn't hear any sounds of jets or engines. the lights were in a diamond pattern, but the craft seemed to have a larger diameter than the position of the lights. we were able to get 1:37 seconds of the end of the sighting. we 2atched as it went east and then seemed to just disappear.