I have a F 350 drw, 4x4 with 4.10 gears how can I improve the miliage. 7-8 towing 14000 lbs, 11-12 driving not pulling at around 70mph. Change the exaust Add a chip? Both? Explosives?

 

Most people who have bought the new diesel have the same complaint. A couple took the trucks back to the dealer and had the updates done on the computer and said their mileages improved to the 17/18 range.

 

Beater, what exactly are the updates for the 08 trucks for fuel economy? And can these be done anytime? My truck is at the dealership as we speak for the 2nd time for a electrical problem. When you step on the brake pedal without a trailer hooked up its telling me i have a wiring fault on trailer like i said 2nd time for this problem. Any idea on this problem?

 

I'm just going by what people have said. The last two times my 6.0liter was in for warrenty work the dealer said there where updates for my computer and they re-programmed it. I assume they did the same for the 6.4 because people tell me their mileages got much better. Call them an tell them about your poor mpg and see if there is anything they can do. Alsoask them if you have the most current updates for your vehicle. Not sure about your wiring issue. I don't have the integrated brake controller. Maybe Hayapower will have some answers.

 

I have a 08 F-350 4x4 with a 6.4L with automatic trans. and 4.10 rearend ratio. I'm having the same fuel mileage problems as others. Just returned from a 6700 mile trip pulling approx. 13000 lbs. I averaged 8.9 mpg. Love the performance but hate the fuel mileage. I have a 02 with a 7.3L and get around 13 to 14 mpg pulling the same load. Any help out there to get better mpg out of the 08?

 

I have owned many 7.3L and loved them for their power and the fact that they still get decent mileage under a load. I didnt know that people were having problems with the 6.4 as far as mileage goes.....I thought that was the idea behind the twin seqentual turbos?!?!?

 

Are their updates? My Dealership has no clue on updates. I really can't see the 2008 6.4 dual turbo getting 17-18 mpg. They delivered mine without est mpg on the sticker. I'm getting 8 towing 16000 lbs and 10-13 on highway, with 3.73 rearend

 

My dealer denies that there are any updates. Currently averaging 14.9 mpg. To get this, I never exceed 2000 rpm's. Boy is the truck a dog at low rpm's.

 

I have a '08 F350 Duelly 4.10with the exact same issue! (7-8 towing 7ton, 10.5-12 hwy). I have found that I can get about 12mpg at or under 2K rpm. Our speed limit in CO is 75 so I am usually running at 80mph @ 2600rpm and get right at 10.5mpg. I have looked at performance filters (not availble yet from K&N) and exhaust modifications (difficult & expensive with all of the emmision sensors and equip.). I am convinced that the gear is killing the mileage so now I am looking at bolt-on transmissions that add a 6th gear to reduce rpm's at higher speeds.

Does anyone else know of any other OEM or aftermarket products that are out there?

Thanks.

 

Welcome to the site Hammerswinger..

Have a look at Gear Vendors Under/over setup..

http://www.gearvendors.com/f2wd4s.html