there is no federal height limit, and states may set their own limits which range from (mostly on the east coast) to (west coast)., as a result, the majority of trucks are somewhere between and high. truck drivers are responsible for checking bridge height clearances (usually indicated by a warning sign) before passing underneath an overpass or entering a tunnel. not having enough vertical clearance can result in a "top out" or "bridge hit," causing considerable traffic delays and costly repairs for the bridge or tunnel involved.