E-450
 

I have a 99 e-450 with 360k miles. Rolling weight is about 11,600. My mileage sucks. About 8.5. Is that all I should expect or can I get more. I should mention that it has a hpop leak that getting fixed and the exhaust manifold has a small leak. I have a edge programmer in it set on 50 horse. How can I up the mileage without spending a but load of money on injectors and a top notch programmer. Or is this about all the better in gonna get. Thanks

Well your hpop leak aand manifold leak will cause a decrease in milage. Fix those first and see how you look then. Tunup basically- new air filter, fuel filter etc will help dramatically.

Make sure you have good oil cause thats what the injectors run on...high pressure oil.

Its getting the hpop fixed this weekend. I'll keep you posted on what the milage does. The filters are good. That oil leaks out to fast I haven't bothered to change the oil. Thanks