2011, f250 6.7 diesel super duty king ranch, 24000 miles,, used to get 19 miles per gallon on highway not towing, now getting 16
city used to get 15, now getting 13
anyone else loosing mileage?, any cures

 

Moved to the 6.7L Powerstroke Diesel forum.

 

Fuel filters changed recently?
Quality fuel? Are you going to the same places to fill up?
Have you kept track of your regen cycles to see if there is any difference in when those occur (miles between, miles during)?

Can you give us some more details on the truck? cab, bed length, gears, wheel size, etc?

I have a crew cab long bed SRW with 3.55's and I have never seen 19 since I bought it (over any sort of distance, cruising down a hill at idle right after a fill up shoots the mileage up but once I run 100 miles it goes back down). My all up average with around 8200 miles on the ticker is 17.4mpg (I have trip B set to record everything, I use trip A as my tank meter or trip meter depending on what I'm up to). For the first few thousand miles I was at 17.9mpg average so I have noticed a decrease as well, 1/2mpg over the life of the truck so far. 17-17.5mpg seems to be about where I am at any given point. I rolled in the driveway today at 17.1. It had dipped down to 16.7 during my trek today though.

 

Very interesting; is this a long term trend or short term? How many miles has it done this for?

 

I'm similar to KC8QV0 but a bit lower, it's probably because the lead in my right shoe. :-)

I have chalked it up to the first 5000 to 8000 miles I was babying it more than I do now. I tend to like to stomp it instead of waiting for someone else in traffic. Where when it was new I would not do that as much.

I'll say this though, when new I took 3 long trips and ran 65-75 mph on the interstate for hours, it never got over 18 even when I would stay at 70 only.

 

Always had factory 20's, Yea look great
Short bed
Gas in the same spots
Seems to have been for a while,but now that I think about it, could be since I put in the Titan 50 gallon fuel tank, but God I love having the distance to empty read between 600 and 750 when full, so it sucks to fill up, today was about 175, but I can run two or three Midwest states without thinking about it

 

Have you changed your fuel filters? At 24000 miles you're past due if you haven't changed them already. Also check you air filter. I'm more inclined to say the fuel filters tho.

 

All maintenance is at local ford dealer, I will check, thanks for the advice, really love this truck

 

5,000 and I used to get 19 to 20 mpg on the highway average. After the trans flash I get
17 to 18 mpg on the same highway, same driving conditions. It seems like I have read other comments about a drop in milage after the update. Although, I will admit I am getting more regens than before. When the truck was new I could make a 200 mi trip without one. Last weekend I had one up and one back.

 

I have a job 2 truck with 3,600 miles on it (so no filter/oil changes). I get about 13 in town and 17-18 on the highway. I have seen a similar scenario on the highway, where early on in a trip I'm getting closer to 20 mpg, then the further I go into the trip (over 100 miles in) it falls off and settles in between 17-18 mpg. That's flat to rolling hills, at 70-75 mph.

(3.55 w/ 20"s stock tires 4x4)

 

The regen is a pain, is there a set schedule or mileage?. And i also agree the Trans update was not painless and could also be a source of mileage going down

 

The regen entirely depends on your conditions - fuel, driving style, load on the truck, hills/flat, etc. The purpose of the regen cycle is to burn the soot out of the DPF. How much soot your engine produces is not a set value, therefore you can not put a finger on when/where a regen cycle will kick in. That would be nice to manually be able to induce a regen. I could make use of that very much as my commute to/from work is about 25 miles. Once I hit the road on either end and let the engine get up to temps I could kick in a regen and be able to tailor it to the miles I have on my trip. With an automatic regen I have no control over it - sometimes I am pulling in the parking lot at work or a mile out from the house.

As to the update/flash - I have yet to get that done. When I find some time to take it in I have been thinking about doing that but the more I hear about it I am not sure I want to. I get flared shifts and some hesitation with my truck and would like that taken care of, but if the flash is a PITA and I loose mileage.... hmm. I will do Epic's shocks/steering stabilizer mod though. I just gotta find me some $$ and time to do it

 

No flash for me and with a 06/10 build date I'm not sure if it would do anything. 400 flash is my only one.

I routinely get 10 to 12 towing and mid 18's unloaded. 65,000 miles on the truck and no change since new that I can tell.

 

2000 miles on mine and I'm getting 19-20 hwy and 15-16 city not towing

 

I seem to be getting better mileage since team flash and 16000 miles. On a trip home I set the cruise @ 75 for 40 miles and got 19.3 mpg, then 65 for 40 miles and got 23.3 mpg then 55 for 30 miles ( that's all I could stand ) and got 27.5 mpg. Trip b has 1900+ miles at 19.4. That includes 35 miles towing 7000 # tt,1000 miles highway ,4 rides for friends so they can see what a truck should do and 30 miles into the back country (1st and sometimes 2nd gear) that really took a bite out of my mileage. By the way I fold in the mirrors when I can and hardly ever use cruise control .