I have a 2008 F-250 6.4L 4X4 Crew Cab with around 119000 miles. I have installed a H&S Mini Maxx, MACH Force XP 5" Down-Pipe Back Stainless Steel Exhaust System with CAT only no muffler, and aFe Power Magnum FORCE Stage 2-Si Intake System Pro-GUARD 7. I have not done any other mods to the truck. I have tried multiple power setting and even no power just DPF delete and haven't really seen a change in the MPG. I expected to see an increase of at least 3 to 4 MPG with these mods and am not really interested in HP gains. I do a lot of daily driving both highway and city. Any ideas on why I haven't seen any MPG gains? Any thoughts on what I need to change or do differently? Does anyone think it is worth finding a dyno to put it on to see what it is actually producing and doing? Is there anywhere in the Fort Mill, SC or Charlotte, NC area that knows what they are doing with mods on these trucks?


Thanks
Mark

 

With H&S tuning I found I got the best mileage on the mild tunes on the tow setting with the S1L trans tune.

 

I think your expectations were very very high. I've never seen anyone claim results like that. Pre-emissions diesels benefited from uncorking the intake and exhaust but I've not seen anyone post any noticeable fuel economy improvement from deleting emissions equipment. You now won't worry about clogging the DPF. You can run to the grocery store without a problem. You can pull into the driveway without having an active regen start. You won't have to clean your DPF. But save money on fuel I don't think so.

 

I have to disagree with that a little. You are 100% correct on how removing the emissions makes the truck much more drivable, it does change the fuel usage. Before deleted on the freeway it was commen to get 17 to 18 MPG, with the goodies removed I see 20-21.5 on the freeway. You should see a difference, I think like me a 2WD truck will see more of an improvement than a 4WD, but there should be an improvement in MPG.
Also how the skinny pedal is used also makes a difference.

 

The only guy I know getting 20 empty highway mpg is driving a 320k mile 7.3 with less restrictive air intake, straight pipe and mild tune. Anybody else I know getting close to that is driving 55 mph on a flat road at sea level with a tail wind. I know guys complaining because they can't break 10mpg with their lift kit and wheels. If I wait till my stock truck shifts into high gear and keep the rpms to just enough to prevent a down shift ... I can easily get 19 empty hwy mpg. But in a state with 70-80 mph speed limits I avg 16-17 hwy. As long as the ECM is controlling how the engine fuels up your at its mercy and I believe the OP is giving a truthful account of real world results. I don't think his experience is an exception at all, based on what I've seen happening. I thought about trying a banks 6 gun but I don't do enough mileage to justify the expense. Its just cheaper for me to run my truck with slightly less fuel economy. I respect your opinion and hope your right about improving fuel economy ... I guess I am saying that I just haven't seen it yet.

 

Well, every truck is different, mine is 2WD which I think makes a sizable difference, and I don't drive 75, but I also don't drive 55. I do believe 65 is a sweet spot for the 6.4 and on the freeway mine is usually in the area unless I'm late for something. I do think 16-17 for a 4 WD at 75 is very reasonable for a 6.4.

 

I am all stock with the exception of the deletes, No Limit Intake and Gearhead tuning. My truck is a road queen and prior to the upgrades I consistently averaged 11.7 MPGs. I was also the type to run around the block more than once until regen had stopped.

After deletes (over a year now) I average 13.5MPG. But with this new setup, it is far to easy to get on it and smile.

My 06 6.0 averaged 14.5 miles but so did my 08 CVPI.

This is all with no idling and hand calculations.

When I first got my H&S, most threads I read about for best MPG gains were with the HD300. The higher the power setting the better the mileage.

*To the OP, make sure your LBF is set to 0. I think default is 3.

 

Have not had calculated yet but my '08 went from average of 13 on the lie-o-meter to over 17mpg now. Mostly city/town driving.

I am using: AFE CAT/DPF delete pipe, AFE Stage 2 CAI and SCT 7015 X4 with Mike's Custom Tunes (PunchIt Performance). I love the setup.

 

Agree, forgot about the LBF, that will make a difference, it did on mine.

 

I just got done doing the DPF delete on a 08 450. I had been running the H&S for over a year and was disappointing with what I got performance wise. I finally finished the DPF delete and this truck now blows me away. The performance gains in the stock mode is more without the DPF than it was with the DPF on the performance tune. I mainly tow with my truck on the highway, but I immediately noticed mileage gains around town as I was getting more distance on the tank. Hand calculated, I was up 1.5 mpg unloaded. Towing, i've been up about 1 mpg. My truck has the 4.88s, so I wasn't expecting an increase and was just after the performance gains I had heard about. Very happy with my setup. You should certainly see some gains on your truck.

I didn't see this mentioned, but did the DPF delete get done in the right order so that your truck didn't default into regeneration? That would kill your performance and engine over the long term?

 

I would think there would be a MPG gain simply because the truck isnt going through regen anymore. That alone would make a difference, but then add the fact that the truck can breathe now and logically that would help as well.
My CC 4x4 100% stock gets 12-13 empty. I have had it looked at several times and they tell me its normal. Im on the verge of a Spartan or Mini Maxx with the expectation that I see a gain in MPG, not to mention better long term engine health. My old 6.0 gained 1.5 mpg with a SCT and there was no DPF in that scenario.

For what its worth, I read forums about the LOM reading really high MPG's once tuned but the hand calculations were more realistic. People are still seeing gains, but not the gains the LOM was reading.

 

My F450 weighing in at around 14,000lbs, and as aerodynamic as a brick, gets better mileage with a heavy foot than it does when I baby it. I re-geared it with 3.73 gears, should've went with 4.10's. But mileage is best achieved in my truck at around 75-80mph. Not what I was expecting when I re-geared it.

Oh, I get 12.5 to 13.5mpg, depending on how hard I push it.

 

The LOM is worthless once you tune, I have on many occasions reset mine and run it for a hundred miles on the freeway and the LOM would be reading 25+MPG, now that would be sweet, but it's all all a lie, hence the term Lie-o-meter.

 

I hand calculate at the pump pretty regularly. I routinely get 16mpg average. That's everyday driving, some freeway, some around town. I have several hundred pounds of tools & such in my shell most days.


Pre cat/dpf delete... I was averaging 13mpg. My H&S is on the stock tune. I did try the higher HP tunes for a few tanks & got even better mileage but, put it back because the foot REALLY liked those tunes.


Im at 190k & counting. I wanna say I deleted at 125-130k.

 

My LOM is exactly 1mpg higher than actual. You'd think this would be easy for the computer to figure out. Now my buddy has a 2013 F150 and his dash is spot on. So, maybe Ford finally figured out how to calculate mpg.