No it doesn't. It is primarily designed to provide routing information. However, it does have POIs. If you looking for clearance information try
http://www.discoveryowners.com/cginfolinks.htm It's an RV web site with overlays for rest stops, Wal Marts, Flying Js, Pilots, clearances and a lot more, that will work on DeLorme, S&T and CoPilot. It also has text files.
I don't know how often it's updated but most states have quit raising and lower their bridges and overpasses :rofl" so it should be OK.
I have a Class A RV and I use it more for WalMarts, Sam's etc.