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Low Clearance Information Sources

Ever since I got my first trailer I worried about low clearances. That trailer was only slightly over 10 feet tall, but every time I went under an overpass I cringed. After upgrading to a 5th wheel and finding out that at about 12' it is 6" higher than was quoted by the salesman, it was time to get serious about clearances.

I found there were several expensive "Navigators" available for truck drivers, and there are books for truckers showing all kinds of highway information. Some states, and even a few cities, publish listings of clearances. There are also federal standards for interstate highways, but waivers are available so even that is not always dependable information. There is a lot of information available on the internet today, but researching it before each trip can take quite a bit of time, and some of the information seems to be well aged.

Then in early 2011 I learned of a website called Low Clearances. These folks have a subscription to a service called Route-1 that provides Point-of-Interest (POI) downloads for most of the popular GPS/Navigators. There are thousands of low clearance locations in the files. They are submitted by users and confirmed by the Low Clearance folks. The files are updated a couple of weeks and you can download them at any time.

I subscribed to the service in March and downloaded the files. The locations are grouped by the clearance height so for my TomTom navigator I loaded the files for all locations with clearance less than 14'. Then I set the POI options in my TomTom to show an icon on the map for all points, and to give an audible signal like a siren whenever I am within 500 feet of a location with a clearance of 13' or less.

So far I have not had many alarms, which was expected since I stay mostly on the interstate except when near a campground I am not surprised. But it does give me a bit of comfort to know TomTom is watching clearances for me. I have noticed that I get an alarm in Raleigh where there is a low clearance on Atlantic at Capital Blvd. I have noticed a few other points when driving around town without the trailer in tow, but none have been on routes where I would take the trailer.

I recently found America's Independent Truckers' Association, Inc. on the internet. They have a listing of low clearances by state. They don't seem to have nearly as many locations as the Low Clearances folks, but it is plain text so if you don't have a GPS/Navigator it could be of use.

In late June 2011, Rand McNally announced the new TripMaker RVND 5510 navigator targeted specifically for the RV owner. It is a bit pricey at $350 but the specifications are impressive. But the jury is still out and I have seen both good and bad reviews for this product.

Do you have information you would like to share with other RVRN Members? Please send it to the webmaster.

Thanks es 73,
K4HM - Hank