'95 Ford Crown Vic,4.6L/281 ci V-8,AT/OD....about 16-18 mpg in town,about 24-26 on the highway....'83 Chevy C-20 Pickup,5.7L/350 ci V-8/AT....8-10 mpg,might get 12-13 hwy if wind & weather is right.(Note: This truck has a 4:11 gear ratio,and NO overdrive.) My '72 Olds 98,7.5L/455 ci V-8/AT(now off road,under restoration)got about 11-13 in town,17-18 hwy.(This is a big "highway car",has a "tall"(2:73)rear axle,but also a lot of low end torque.)Subtract about 10% on mileage for all above if raining. Use 87 oct in Ford & Chevy,used 87 or 89 in Olds,depending on outside temperature.(89+ if really hot,or it 'clatters' some?)