I run Mobil 1 10W-30, and after 2.5 years with the car and ~30k miles(156k total) i get 30mpg highway with 21mpg city (economode - accelerating slowly and shifting at 1500rpm)
my mileage is 20% better than sticker, is this weird/normal?
I get 17-18mpg city, 23-24mph highway at an average speed of 75mph. I have a 3.73 and it's the same consumption as when it was bone stock with a 2.73 rear end. Still better than the 15/22 EPA estimates.
i get between 250 to 170 per tank on my 1990 5.0 depending on how i drive. my car eats gas. So im probaly getting only about 17-18 mpg when you factor in im not runnling my tank completly dry.
__________________
1990 Mustang 5.0 LX Standard with a forged lower half, mild racing cam, aluminum racing driveshaft, bbk cold air intake, short throw gear box, aluminum H pipes with headers, roll cage (welded), 8.5 MSD sparkplug wires, MSD distributor cap w/ rotor, E3 sparck plugs
I can get about 21 highway with all the mods below, but that rarely happens since its my toy and not my daily driver
__________________
1988 Mustang GT, TTops, 306, AOD with 4r70w gearset and shiftkit, E303 Cam, Ford Racing headers, BBK H-pipe, Flowmaster Cat Back, 3.73's, Traction lok with F150 spring, Eibach lowering kit, B&M Tork Master 2400 Converter, trans cooler, C&L 76mm Mass Air, Accufab 70mm throttle body, K&N filter, Mass Air conversion, Subframe connectors, Lots of Polyurethane, 210HP at 4500rpm, 272 Torque at 3600rpm at the wheels, best 1/4 mile: 14.12
Well with the way I drive... I average 16.5 MPG. That was before my intake swap, but I doubt that changed the mileage any.
I like go full throttle when I get up to speed on an interstate a lot.
__________________
-1994 Mustang GT... K&N filter,GT40 tubular intake,BBK Full Length Headers,modified midpipe & Flowmaster muffs, timing at 12*. Best time- 14.74 @ 93.16 -Check profile for pics of our car collection! -Member of MBMCustoms Car Club - AmericanMuscle ROCKS!! - "Save a horse, drive a Mustang!"
What's your MPG? 
