The site
http://www.lowclearances.com/amember/go.php?r=1827&i=l0">LowClearances.com
is a great site. You download this to your computer and then into the GPS, go into the GPS BEFORE you go on the trip and plan the trip and it will show you where the low clearances are and will allow YOU to reroute. Seems to be what is in the DEZL GPS so you could download this into your own GPS and have the same thing as a trucker GPS as long as you update your data every year.