DPF/CAT deleted, MPG got worse, WTF?

[supersecretsquirrel]

Howdy all.

Would love your feedback and or ideas.

2008 F-250 Crew cab 4x4 XL w/135k miles

Installed Flo-Pro DPF/CAT delete pipe and S&B Air intake.

Running H&S XRT-Pro programmer.


After install, running stock power and S1M transmission tune (default), my mpg dropped by about 1 - 1.5 mpg.

I was getting about 15 to 15.5mpg. Dropped to mid-low 14's.

Been trying different transmission tunes (S2L, S1L) to see if that helps. Nothing better yet, and sometimes worse. I do a lot of back country driving with hills, 40 - 55 mph, right in the shifting zone.

Was running the standard tune with stock power. Tried switching to the "EASY" tune with stock power. (I only need the + power for occasional trailering applications - getting up the steep driveway with the full10k on the 5th wheel)


For those with experience with these trucks and the various tunes....

What can I do with the XRT-pro and tunes available to squeeze every last drop of MPG out of this truck?

I know, I know, this stuff is supposed to be for performance enhancement, not MPG savings. Look my needs are for longer life and MPG, and plenty of folks talked up the DPF delete as the solution for MPG on the 6.4

I sunk a lot of money into this with the expectation of a big boost, and it ain't there. in fact, it's worse. I know the life of the engine should be better now, and that's good, but my wife is gonna kill me if I spent $1,500 and the MPG got worse.

So, what am missing? My local diesel guy told me to plug back in all the EGT sensors and the pressure sensor that I had unplugged when I deleted the pipe. I did, and at first it seemed to help with the idle speed a little, but has not made any noticeable difference on the MPG.

But the XRT -pro instructions said to remove these, so I am confused...

How do you make these trucks sip fuel?

I also have a flo-pro EGR delete kit I am waiting to install for some good weather / time (working outdoors). I would hope that would help a little, but I know the XRT-pro is already disabling the EGR, so not much I would imagine.

Are there some obvious problems that could be causing this failure to improve that I should look for?

Thanks in advance for all your help.

Ben

[WildStyle]

Run the hottest tune you have for every day driving and keep you foot out it.

[supersecretsquirrel]

Originally Posted by WildStyle

Run the hottest tune you have for every day driving and keep you foot out it.

Wildstyle - thanks for the reply.

I was wondering about that. I saw a couple of other posters in other threads suggest that the hotter tunes gave better MPG with a light pedal.

My question is this. Do I risk damaging the engine if I do that, and then I have to floor it (avoid accident, emergency driving, pulling a trailer up a steep hill)?

I have the S&B air intake, so I guess I have enough air for the hotter tunes, but will my exhaust handle it? I never really approached this whole project thinking about the hotter tunes. I just assumed the since my goal was MPG, that the delete would produce it with stock power.

Any advice on the EGT sensors and pressure sensor from the CAT? I currently have them plugged in and zip tied up out of the way. I've heard leave them plugged, and I've heard (from H&S) remove them/ unplug them.

[the-last-international]

Unplug them and run on hot

[acelay]

I was curious of that as well. Could running it on hot with a light foor be any worse for the engine than on wild or mild in any way? How does the hot tune provide better mpg?

[the-last-international]

Originally Posted by acelay

I was curious of that as well. Could running it on hot with a light foor be any worse for the engine than on wild or mild in any way? How does the hot tune provide better mpg?

I have 90k+on hot tune. My 6.0 had 310k. The people with problems have either abused their trucks or bought used ones that were abused.

[the-last-international]

Originally Posted by acelay

I was curious of that as well. Could running it on hot with a light foor be any worse for the engine than on wild or mild in any way? How does the hot tune provide better mpg?

It adds horsepower so it takes less time to get the truck rolling and less energy to keep it going.

[atwoojr]

Originally Posted by the-last-international

I have 90k+on hot tune. My 6.0 had 310k. The people with problems have either abused their trucks or bought used ones that were abused.

I dont mean to hijack the thread but you have 90k miles while running the delete and being tuned? Any issues at all, even minor?

[the-last-international]

Just the tensioner pulley. Before tunes I had radiator and a few egr problems. And my Dpf clogged twice.

[supersecretsquirrel]

Originally Posted by the-last-international

It adds horsepower so it takes less time to get the truck rolling and less energy to keep it going.

OK, I'm willing to give that a shot.

Now, I have to ask, when you say "Hot" do you mean the HOT level on the standard H&S Tune (250HP w/ DPF Delete) or the HOT power level on the "Hot Damn" tune (300 HP) or the HOT power level on the "Easy" Tune (175 HP).

What Tranny Tune do you use?

I'm going to try the "Hot Damn 300" and see what I get with a real light foot.

Also going to try S2M. see how that works.

Any other ideas out there?