Oh. Heavier than a pickup, but I'd still want more than 15 mpg on a straight, flat highway at a legal, steady cruise. Especially with that 3.55 ratio.
First the compression test, then an ignition tune-up. After that look at the carb. That would be my plan.
Of course, an inspection of tire condition and pressure would precede any of that. What rubber are you running, by the way? OE 16" tires would be a definite negative in looking for economy.
