Oregon Revised Statutes Oregon Vehicle Code § 803.425

(1) Special use trailers and travel trailers are measured from the foremost point of the trailer hitch to the rear extremity of the trailer body not including the spare tire, but including all ordinary equipment or appliances appropriate to the type of body such as stakes, curtains, hooks, skids, tailboard, chains, sides and roof.

(2) Campers are measured by overall length from the extreme front to the extreme rear.

(3) Motor homes are measured by overall length from front to rear extremities.

(4) Tent trailers are measured by overall length when folded for travel.