bad mileage...wasup??

[thomasinnv]

2000 f350 7.3 auto 4x4 with super chips 1705 in tow safe mode. (no flames please, it came with the truck)

i am averaging about 15 empty, and 7.3-8.0 loaded (11,000# fifth wheel)

this truck is new to me, so i don't know if these numbers are to be expected or not, but it would seem to me that it should do better than this. I have changed the oil and filter, and a new air filter. i don't have a boost guage yet, but i can hear the turbo whining pretty good, and it's obvious when you step on it when the turbo spools up. part of the reason i upgraded to a diesel from the v10 was for increased mileage, but i got this good with the v10. what are some things i should look for?

i was thinking about going back to the stock programming, but don't really want to lose power for towing. would the tow safe tune cause me to eat more fuel? (i would guess so, but this much?)

thoughts please?

[siloped]

Thats about what I get unloaded too. But other people on here claim 17-18ish.

Just wanted to let you know you are not alone

[Stroked7.3]

I have the same setup. You need an intake and an exhaust to get any kind of performance out of it. With my programmer in Tow Performance i can get 18-20 dependinng on how i drive it. But ill be getting rid of my superchip for a TW very soon.

[thomasinnv]

Originally Posted by Stroked7.3

I have the same setup. You need an intake and an exhaust to get any kind of performance out of it. With my programmer in Tow Performance i can get 18-20 dependinng on how i drive it. But ill be getting rid of my superchip for a TW very soon.

i have been contemplating the diy intake mod. i assume that will help with egt. i hesitate on the exhaust though, i read somewhere that going to a larger exhaust will sacrifice low end torque...any truth to this?

the exhaust will have to wait a while (no funds right now) but the intake mod i can do right away. will that help with mileage?

[somebodyelse5]

Originally Posted by thomasinnv

i have been contemplating the diy intake mod. i assume that will help with egt. i hesitate on the exhaust though, i read somewhere that going to a larger exhaust will sacrifice low end torque...any truth to this?

the exhaust will have to wait a while (no funds right now) but the intake mod i can do right away. will that help with mileage?

no, not true at all. on a gasser motor, you need a little backpressure for low end torque. on a diesel, the better it can breath the better it can run. get an intake and an exhaust (4" or 5") and you will see some gains in mpg as well as power.

think about this, you have a turbo moving the air, no back pressure either way.....right?

[AaronATX]

yeah a 4" down pipe will eliminate some backpressure and maybe some low end torque. i have the 4" turbo back though and I dunno.. it's still very torquey. especially with the chip.. i can sit down low in the 1200 RPM range coasting no problem at like 40-45mph.

the intake.. tough to say. it might help a little but without a tuner intake and exhaust aren't going to do as much. a tuner will really take advantage of the increased flow. you should notice less lag with the intake.

[AaronATX]

ok maybe not haha that's just what i heard. i dunno

[somebodyelse5]

Originally Posted by AaronATX

ok maybe not haha that's just what i heard. i dunno

based on what ive read here, you wont loose torque from an exhaust. simply because you have a turbo, needing backpressure is then counter productive no?

but you will see improvements with tuner, intake, and exhaust. tuner=brains intake=lungs exhaust= butthole lol. the more air it can move the better it will run.

stock, i got 16-17 mpg highway unloaded. now i get 20+ or - 2 depending on hills and what not. city milage mainly comes down to the driver, drive her real nice and it will get better mpg, get her to shift sooner and keep your rpm's down. but once you get your tune, intake, and exhaust, you will have alot of "fun" so your milage might go down

2000 rpm is supposed to be the sweetspot for milage.



aFe stage II if you can afford it, otherwise go with the DIY intake.
i would call gus at farmboysdiesel for the exhaust, he will get you a smokin deal!
and for tuners, TW or DP. Im running an edge, but i need a TW lol.

[siloped]

All you really need to do right now is just cut the muffler off or put a muffler delete pipe in place of it.

I did my DIY intake before I Had tuner and it was a very noticable diffrence. The intake and exhaust are definatly worth doing before a tuner.

[Hank]

One thing I didn't see in your post was fuel filter. Always good to start with a clean one when you are starting to diagnose issues.