So, im fairly new to truck modifications.. So please take it easy on me.

Im not a Fanboy of any particular make.. but i do have to say, I had a 07 5.3L Chev Silverado and it got much better gas mileage then my 08 5.4L F-150 and felt like it had more power to boot.

I am getting around 12.5 MPG on my truck .. it seems much worse then it should be. Today I installed a Hypertech Tune and a K&N Intake on it, hoping to do anything to it to make it slightly better on Fuel when i play nice, and give it a bit more power. Obviously I havent been able to calculate the MPG on it yet, it doesn't feel like it has all that much more power though. It defineatly sounds cool though.

My question is basically, the tuner asked If i wanted to modify the shift points, and the shift stiffness? Could I stand to gain power or fuel efficiency by changing the shift points? and Could somebody explain to me what exactly it means by shift stiffness?

My 07 5.3L Chev Silverado got around 17-21 MPG and Im getting 10-13 MPG on my 08 5.4L F-150.. with seamingly less power.. What gives? Does this sound wrong to you? Is there anything I should look at? I did buy this truck used so maybe there is something wrong with it, but I am missing what exactly it is... The rated MPG for the truck is 14-17.. and Im not even getting 14...

I realize Ive asked quite a few questions.. but any help on any of them would be much apprechiated

 

Unfortunately, Ford Trucks are somewhat notorious for having a wide range of variation when it comes to fuel mileage. Some do really well, while others with essentially the same truck, get bad mileage.

Remember your 5.3 had that AFM, which shuts off cylinders when the load is light. At least that's how I think it works, never had one. But that feature is probably why the MPG on the 5.3 was better. Not to mention Chevy typically runs highway gears vs the common 3.73's that are likely in your truck.

When it comes to modifications and all. You can spend tons of money for virtually no MPG gain. I ran a Gryphon with custom tunes on my 07 for a few years. It sure helped improve the driveability of that truck, but did nothing for my MPG. At least the MPG stayed pretty much the same.

To improve MPG you need to drive conservatively. If you spend some time reading about methods that the trucking industry uses to improve MPG, you might find some techniques/methods that can be applied to your truck. But there is no magic fix for this.

 

SVT is right about your driving style and the points about the Chevy. The Chevy is also lighter...contributing to the mileage differences.
Can you return that Hypertech? If you can...then give Mike Butler @ 5 Star Tuning a call for a custom set of tunes for your rig. He'll address all your concerns and send you the loaded device.

 

You neglected to indicate how many miles are on your truck. If you have a few (30k or more) it is probably time to change the fuel filter which has been shown to be a cause of sub-par fuel economy, especially if crappy gas has been used in it much. Tire inflation should be checked, also. And, if it was me, I would disconnect the battery for long enough to clear the CPU's transmission memory. These transmissions "learn" as you drive and adjust the shift points according to your driving style. If it was run hard previously, the powertrain controller will shift accordingly, lowering your fuel economy. The Chevy , as mentioned by others, is several hundred pounds lighter, and the 5.3 is quick revving and an HP motor. Put 5000 lbs. behind the Chevy and your F150 and see which one feels more powerful then. The 5.4 is about torque. Good luck!

 

Some good points.

The truck has 100K kms on it (around 62K miles) and I bought it a few months ago. I belive it was probably a leased truck, so im guessing the owner did nothing for maintainence. I will definetly look at the fuel filter.

I did disconnect the battery when I was installing the Intake on it, It would have been disconnected for around 3-4 hours. That should be long enough to reset the "transmission Memory"? I didnt even know they had this feature.

I have a work vehicle so I dont put very many kms on the truck, It takes up to a month or two to use a tank of gas. I cant complain too much about the cost, but I still don't want to be driving a tank unnessarily. I'll try for the next couple months to drive a lot more conservatively and see what difference it makes.

I would be interested to find out what highway speed is the most fuel effiecient.

Anyways, thanks all for the comments.

 

I will put in my.02 here.Some may not like it,but here goes!
First off,Modifications will ultimately hurt fuel economy.I have seen in the past folks putting on "cold air intakes",and the like to improve mileage.
The only way you are going to get the most out of your Ford is to leave it stock,and perhaps buy a ScangageII. Hook it up to your OBDII port,and drive it using the display.I bought mine from AutoZone,and while I do NOT like A/Z for anything other than oil,filters,and Batterys,it has helped change my driving habits.I also dont work for A/Z...just a firm believer in the unit itself.
Mods such as tuners,and the like will get you more,and better performance(no argument whatsoever) but will not help in the fuel economy situation. The ScangageII will readout quite a number of parameters,such as Tach,AVG trip mileage,and real time fuel usage.I personally keep my 07 all OEM,and with this unit,average around 21 mpg. It paid for itself in a month or so.I purchased the optional rear view mirror mount as well.Mounts above the mirror,and has an extension cable to the OBDII port. No wires visible,and it looks stock...You even have hundreds of background lighting options built in.

 

Great advice so far. Also if you try to keep your rpms just under 2000 when accelerating you will be surprised how much your mpg will increase. Even if you actually don't, subconsciously you will begin to ease into the throttle and your driving habits will change. Just easing into 1st gear and through the shift into 2nd will give your mpg a boost.

 

N5926G.....where did youbfind the mirror mount for your Scanguage? I just bought one and love it so far but haven't found the mirror mount yet.

 

It was in the box paperwork with the unit.If you didnt get one "google" the scangageII,it should have the optional equipment listings.

Otherwise get back with me,and Ill see if I if I still have mine

 

I think you're going to find maintenance, brand of fuel and driving habits will have more effect on your mileage than anything else. I have a 07 Scab longbed, 5.4L with 4.10's. Bought it 2 years ago with 22K miles and best mileage was 19.3 mpg highway. I keep up on maintenance, 55 psi in tires (E rated) and just had the plugs changed at 42K (currently at 44K). My truck also seems to like Shell or BP 87 octaine gas best. Being this is Minnesota, all you can get is gasahol here, so that makes it a little worse than if you use straight gas.

Just did a 500 mile roadtrip, kept the rpms at 2K-2.1K, I used cruise as much as I could. Got the best mileage out of it so far: 20.6mpg and I've been keeping records on it since I bought it. Right now I'm still running the steel rims and winter treads. I hope for even better once I put my summer tires back on, alloy rims so there's a definite reduction in weight too.

My first trip was when I bought it in L.A., Calif and drove it home to Minnesota and that's when I got the 19.3 so I do have some highway history on it.

 

I do agree with you on a lot of what you said, but I have to disagree with what I bolded from your post.
Saying that tuners will NOT help fuel economy is a false statement.
It is true that tuners are not usually designed to increase economy, but they do provide very useful additions such an increase in low end torque, that can assist the driver in obtaining higher efficiency than before the tunes.

I do agree that driving style/habits are probably 80% of the equation, with terrain and traffic also contributing, but optimising the engines output does help in a variety of instances. The occasional increase in economy is just a by-product of those other increases if you're lucky.

 

Not to step on your toes ng, but when I first got my truck I was only getting 9 to 11 mpgs highway. After doing some "mods", CAI, tuner, exhaust, bed cover, etc. I squeezed out 13 to 15 mpgs, and that was even after I put a box in the back LOADED with tools. After a bit of mileage was put on the truck, those mpgs started to drop back down. I've posted this in another thread but I will state this here as well, I just changed out the coils, injectors, plugs, fuel filter and so on (all of it was needed, 189,000 miles worth) and I've increased my mpgs to around 15 to 18 mpgs depending on how I drive, which as everyone else has stated, is a big contributing factor to what kind of mileage your going to get. I get the best mpgs on the highway with the cruise control set at 55 mph. Your mileage will drop in the winter when fuel companies put out the "winter blend" fuel, which in my opinion is just another way for the oil companies to rape us for more money with the increased stops at the gas stations.

And oh yeah, regular maintenance, oil, filters, tire pressure and the like will keep those mpgs going.

 

No worries,Not offended in the least.I have just seen in past years folks doing things to their rides,that hurt economy,value,and reliability.Thats not to say mods are a bad thing.I just prefer to keep my baby stock...... Most of my driving is with an empty bed,and occasionally a load of Mulch,or Plants(Honey-Do,s).I did notice that when I got the ScangageII,and watched it,it was amazing to see just what driving habits can do,and how to change them.

 

Howdy Y'all!

I recently installed a GForce chip on My 06 Lariat 5.4.. I have gone up at least 60k's per tank (96 litre) combined highway city driving in canada!
the chip was resonable and easy to install.
Next is a cold air intake system to see what happens!
Cheers!

 

+1 on driving habits.
I've hand-calculated my mpgs since getting the truck new. Since I got my F350, the wife's been driving the F150

I can squeeze about 14.5~15mpg in town empty. No jack-rabbit launches, rpms rarely go above 2K unless I need to pass a guy texting, and I drive to avoid needing to brake hard. In other words, I'm driving almost like gramps!! When the wife drives the similar routes, she's lucky to get 13.5mpg. For a while, I thought something was wrong with the truck so I drove it again for a couple of tanks; mpgs went right back up. The kids complain they get car-sick, er, truck-sick, when mom drives, and when given a choice of who should drive when we all go out, they insist on dad driving

I left my spare in the garage. That's 100lbs less to spend fuel accelerating all day long, and 100lbs more hauling capacity when I need it.

With that said, as bad as my F350's mpgs are, I get about the same mpgs driving that compared to the F150.