Opinions on gliders

[Texasdude74]

Most gliders built aren't done for max fuel mileage. They more often than not don't utilize wide single tires, very tall gearing, any kind of aero or single screw differentials. They're also, not typically driven at 53 mph. So, their mpg isn't stellar, usually in the 6-7 range. Their advantage is in their ability to go over a million miles with minimal shop time and ease of repair when they do break.
A modern, low rolling resistance aero truck driven at 11-1200 rpm might save you $2-3k per year in fuel. Some of that will be given back in Def fluid, but many times that amount will be given back when the engine requires a tear down every 2-3 years with multiple check engine lights, sensor failures and firm ware updates along the way.