View Full Version : MPG with your 425?

06-24-09, 03:16 AM
My 79 Sedan deVille consistently averages 11 city and 14 highway. I check the mileage once or twice a month and every fill up on trips. It rarely differs, highest I recorded was 15 highway and I do not recall ever getting lower than 11. I drive slightly above posted speed limits in town, I'm not afraid to step on the gas and run the AC, and trips average 75 mph. Car is original, professionally maintained, 425 4bbl, and is used almost every day. I have owned it for about 5 years and it has been driven from 61k miles to 85k miles. How does that compare to yours? Dave