Since I started working in a warehouse I have noticed more and more 14 wheelers…(semis with a 6 wheeled tractor). Is there a reason for using a 10 wheeled tractor over a 6 wheeled one?
My WAG is it has to do with the weight of the trailer being pulled.
It would be strictly based on the weight capacity. A 14 wheeler is much easier to turn and will be an advantage if the extra weight capacity isn’t needed. Note that there are 4 wheel trailers also instead of 8 wheel, giving you the potential of a 10 wheeler.
10-wheel (or more) tractors, in general, are over-the-road. I’d guess that the 6-wheel tractors you’re seeing are only hauling in and around Lexington. I’d further guess than none of hte 6-wheel tractors you’re seeing have sleepers.