new diesel owner

[2005lly]

Hi there! I've just bought a 2005 chev crew duramax lly about a month and half ago. this is my first diesel truck. I'm trying to get the best fuel mileage I can out of it, so I've added a edge ez 65hp chip and will be putting on a MBRP 4" turboback ss exhaust on thursday and hopefully shortly after that I will be installing a S&B intake kit also. not really looking for horsepower gains just mileage increase. My wife filled the truck up today and she calculated that we're only getting 10mpg!!! this can't be right. I think it has to be the stock exhaust/intake and the winter diesel fuel being the problem. the truck doesn't pull anything nor is it used for a work truck. any suggestions as to why I seem to be getting poor fuel mileage? I've tried a programmer a diablosport to be exact and the truck wouldn't take it. I've got bigger tires on the truck 285's. is there something else I should be looking at? any input would be great. I really like the edge product not too keen on pulling fuses with a programmer. thanks.

[06duramaxkid]

maybe change ur fuel filter.. it might be clogged

[2005lly]

changed the fuel filter last week, still poor mileage like 10mpg!!! read a few posts on here some guys said getting rid of the cat will help dramatically, so i'm putting on a turbo back exhaust on thursday. I think the winter diesel has something to do with it too. I'm also using a fuel conditoner to from the place where I've bought all of my parts from. thanks for the input.

[naterik]

if your speedo is not re-calibrated for the larger tires you are actually getting better milage than you think (not tremendously, but some), i believe i've read arround here somewhere on this forum their is a link to a graph that gives you the percent of difference to figure for tire size differences

[2005lly]

Yeah thats what i've read too. so i'm actually getting worse mileage? I'm kinda wondering if my cat is plugging up. I bought the truck a month and a half ago, I live in canada and the truck actually came from the states. I tried using a diablosport programmer but the truck wouldn't take it so i switched to the edge ez. The diesel shop where I get my parts from said it might be due to my alarm system or that there was another programmer in there before. is there anyway short of taking the truck to the dealership to set the computer back to factory settings? i think it was just because of my alarm. but the fuel mileage really does suck!thanks for the input.

[Hammer 4]

Also, if your using "winter" fuel, you'll see a drop in mpg's. Most of the guys complain that they get worse mileage in the winter due to the fuel, compared to non winter fuel.