I have a Garmin Quest GPS and it has a setting for "Trucks". I have not used this feature though but I do us the GPS ALLOT on my motorcycle for funeral escorting and it works great.
The biggest down side to the GQ is that you have to load the maps on it from your computer. It will hold 2 to 3 smaller state maps and 1 map if the state is a bigger one like CA or TX. Although the Garmin Quest 2 comes with all the detailed maps for the whole U.S. preloaded. Much better if your traveling all over.
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