I saw another one of these on 405 yesterday...perhaps it's on it's way from Everett to Renton?
What you are seeing is a tractor hauling a module. these are parts of wings. the "car" is a "steer car" it used because the length is to long, and the driver steers the trailer around. These set ups run from Fredrickson to Everett. it takes a team of three drivers pilot car, (to help the truck out, tractor driver, and steercar driver, or "tillerman." all three rotate from position to position. I hope this info has been helpful.
Thank you Anonymous! The ones I saw were traveling away from Everett, so maybe going to the Fredrickson plant?
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