Curious what other 4.2 V8 (non-FSI) owners are getting for fuel mileage. I average 15 MPG with 50/50 highway and around town. I run 91 Octane gas. I've changed spark plugs and air filters in hopes of squeezing a little more out of it with negligible effect. I have 18" Manhattan rims with 255/55 all season tires. Please post your mileage. Runs great, just not sure if this type of mileage is normal.