im new to the ford experience. i bought this truck for a number of reasons one being that i killed my chevy , so i upgraded to a 06 king ranch 6.0l turbo diesel f350. basically iv been told that switching to a diesel would gain me any where from 15 to 20 mph unloaded and towing a 6000 lb trailer would drop me to arould 13 or 14 mph. this could be farther from the truth for me currently i get 10 with the trailer witch is better than the chevy but with the cost of diesel their is no off set, and with out the trailer im getting around 13. iv read a few things on the truck one being that a fuel management problem could be to blame im not sure. but if any one has any hints or tricks or if a programmer is the way to go, i would be vary thankful. my other question is in the morning i start my truck up and let her run for about 5 mins or so some times less. she starts fine but driving down the road for the first 5 to 10 mins she doesnt up shift at all . now i hope im not doing any damage to the motor by hopping in it and driving away or is this just common with diesels and i need to let her warm up a bit. sorry this is so long but thanks for any reply's.

 

I will assume you mean "MPG" and not "MPH". These trucks can get the 15-20 MPG that you mentioned, which is a really wide range. Running empty at 65 MPH, I think most guys get about 16-17, with stock gear. I've gotten as high as 18, but not often.

Around town 100% I barely get 10 MPG.

Pulling about the same trailer as you I get between 10 and 12. That's pulling up and down the Sierra's grades.

If you are getting 13 running highway empty, that's on the low side but not unheard of. If that 13 has some city mixed in, then it sounds completely normal. If you have oversized tires or a lift, then that hurts mileage a lot.

There is no need to warm up for 5-10 minutes. Start it up, give it a minute to get the fluids flowing, and go but take it easy for the first few miles.

I don't understand your tranmission issue. Are you saying you are in 1st gear for 10 minutes each morning? That is definitely not right. But if you are saying the shifting is late for the first 5 minutes, that is normal. Mine shifts at 3k RPM for the first mile or so, and power feels low during that time.

 

I average 16 mpg. Strictly city driving about 14 mpg. What gears are you running? Is it a dually?

Diesels don't create much heat at idle, so warming it up for an extended period of time is just gonna clog you're egr system. I start mine for about 1 minute and then take off. Until she's good and warm I just keep her under 2000 rpms. In drive, keeping my foot out of it, even cold my truck shifts below 2000 rmps through every gear.

 

First off, no matter what the vehicle is, don't believe what people say on what you should get for fuel economy. Even if they have the same outfitted truck as you, there are different variables that come into play, some you can control, some you can't. They might be getting what they claim as far as MPG goes, but that doesn't mean that you'll get it(or really should expect to get it).

Second, tuners are first and foremost performance enhancers. You may see MPG improvements, you may not. You might even lose MPG after the tuner. This is going to be like what you heard about the gains on the mere fact of going to a diesel over a gasser, it varies. Now if you want to go the tuner route for whatever reason, I would suggest custom tunes both to give you the best chance that you can have with improving MPG and also, due to the fact that the 6.0 does better with custom tunes then it does with off the shelf tuners. I would also avoid anything that says "shift on the fly". If it has it on there, don't get it. Also stay away from a/m intakes, they won't do you much good with a 6.0 either.

Third thing is have you done some of the more simple things that might affect fuel economy? Checked your fuel filters to see if they are clogged etc? Even if you changed them 600 miles ago, you could have still filled up with bad fuel. Bad fuel doesn't care if the filters are new or not. Checked your air filter? Even an errant sensor reading can get you poor fuel economy too.

Or, you might just have to accept the fact that it is what it is with regard to what you are getting for fuel economy with that truck. No one ever likes to think about that, but sometimes it's true.

 

And don't forget to check your tire pressure. Low pressure kills mileage.

 

yea its a dually i have no idea what gears are in it. i replaces both fuel filters and put a k and n air filter kit in it i run it in 2 wheel drive all the time and with the lock outs off...... i guess i should just deal with it. lol i love the truck tho pulls the trailer with no problems....

 

I would highly suggest you take off the K&N intake as it isn't doing anything for your truck and give it's poor filtration, it's got a few dusted engines under it's belt.

They don't flow more until you hit about 3700 on the tach, well outside the usuable range of a stock or tuned 6.0. Then you have the filtration issues as well. The only "good" thing about it is that you can clean it and reuse it, but that's it. I'm at 508 HP and there are people running more horses then I am and still use the stock intake and it takes more then an aggressive race tune to get up to that HP level.

Find a stock intake, they actually got it right stock this time.

 

Also here are my driving conditions I live in up state NY most of my driving is done on the express way any city driving is usually done after getting off the express way. Um that dam k and n was really expensive does it give anything as far as performance or MPG. O and the shifting it only does it in the morning and for about 5 mins . It does exactly What was said above.

 

Unfortunately no.

On the 6.0, the K&N does not flow more air then stock until you hit 3700 rpm. Stock or tuned 6.0 peak HP/TQ happens at 3300 and 2000 rpm respectively. That intake doesn't flow more air until you are outside the rpm range of the truck. It does flow more, but the problem is when it flows more. In order for it to work, you have to raise the rpm range of the truck, we are talking modified injectors, bigger turbo and a fuel system to support the higher fuel demand, along with studs for the heads.

Unless you are already planning on doing all that, it is far cheaper to just go back to a stock intake system.

As to mileage, there is not one person alive that can prove beyond a doubt that any one mod is responsible for gains in mpg. There are way to many variables, some of which you cannot control, to say that it was indeed this one thing versus another or a combination of both of them.

At best a person can say, I put the intake on, I noticed improved MPG, therefore, putting the intake on the vehicle improved MPG. That doesn't logically follow in of itself. I can think of pretty out there examples that would follow that same logic of: I did A, observed B, therefore, A caused B.

 

Ya, I've heard a few dusted engine stories due to k&n intakes too... I'd get rid of it.

If you have a dually you probably have something like 4.10 or 4.30 gears which will lower your mileage some compared to the srw's with 3.73's.