I had a 2010 Frontier Pro-4X crew cab (4.0 v6/5sp auto) for about 5 years and accumulated 87k miles (bought at 40k, sold at 127k). Other than routine maintenance I never put a dime into it. I was pretty religious about tracking mileage and over the last several years and >40k miles I averaged an honest 19mpg, including towing a 2500 lb pop-up for several thousand of those miles and with relatively heavy LT E-rated BFG All-Terrains installed. I agree with TOM about the towing from a power perspective but even my ~2500 lb pop-up camper would push the truck around in strong winds and buck over sizeable heaves in the road. The only reason I sold it was to move into a bigger truck (F-150). Given the current offerings in the mid-size market I'd go back to a Frontier without a second thought if my needs changed.
