OP HERE: And the answer IS! 18,000 pound commercial weight limit on Chuckanut Dr., which is the main road to park from the north or south I5 exits.. By the time we saw sign - there was no turning around. If the weight police had stopped us we might have come very close to 18,000 without driver and passenger. I didn't understand the "commercial" weight limit restriction. We arrived at park with no problem. Have to assume Washington State park personnel knew about weight limit and did not post that info on website.
BTW do not try southern approach to park entrance. Use I-5 exit 250 and come in from the north.
Suzie & Chuck USNR USAF USCGA
Challenger Owners Club
2015 37KT Challenger, Demco Commander tow bar, Ready Brake, Sewer Solutions, Safe-T-Plus 41-230, 5-Star tune with 2014 Ford Fiesta behind us & 385 FastTrack kayak inside.