2012 F350 ford dually with 6.7 diesel

[richard_123]

neighbor in rv park having trouble with ford truck listed in subject line. pulls a toy hauler about 40 feet in length. had been using a programer on the truck which has 3 levels of performance. has programmer set level 3, the highest level of performance for power.

problem while pulling from Florida to mountains of Virginia the truck would be pulling along just if, and he would begin loosing power to the engine, have to pull over , shut engine down. when he sat a few minutes and restarted the engine and begin to pull again the scenario would happen again sometimes within minutes, other times hours. when he got to the RV park we looked at fuel filters very dirty--changed both. he reprogrammed the truck back to the least of the programs(1). drove truck without 5th wheel around the mountains, seemed to work fine. should we move the programmer setting back to top level and see the response. All this is being done without the toy hauler hooked up. or should we be looking at some other issues. He does not want to break down the 5th wheel till he is ready to leave. Any suggestions or anyone had similar issues?

[BB_TX]

Get rid of the programmer. The 6.7 does not need it.

[jus2shy]

Another possibility is that his HPFP may not be able to keep up with providing fuel for those constant high HP runs. With Ford's latest 6.7, they actually stroked the HPFP to provide the fuel volume needed to maintain 440hp in a tow situation.

[FishOnOne]

Hank85713 wrote:
I believe that the majority of programmer instructions indicate to NOT use the highest setting when towing! I dont have a programmable tune, but the reading I have done indicates so. He may be defueling due to high egts which he would not know if no gauges are present. try the high setting without towing and see what happens, but tow in the tow or low to mid setting would be a better idea.

X2

[Hank85713]

I believe that the majority of programmer instructions indicate to NOT use the highest setting when towing! I dont have a programmable tune, but the reading I have done indicates so. He may be defueling due to high egts which he would not know if no gauges are present. try the high setting without towing and see what happens, but tow in the tow or low to mid setting would be a better idea.

[Golden_HVAC]

It seems like you described the problem that he had very well.

He bought fuel from a dirty source, and has already solved the problem by replacing the fuel filters.

Chances are unless he has run the fuel tank down near 1/8 full, that there is still a bunch of dirty fuel still in the tank. My suggestion is to run the fuel tank to around 1/4 tank or so the next couple of times, to use up as much of the old fuel as possible.

Setting the power to stock or '3' will have little change in the quality of fuel in the system. He will probably need to change the fuel filters in another 3,000 miles once all the 'bad' fuel is gone. This will return the system to factory new performance! Restricted fuel filters can make a diesel run really bad. From what you described, there was a lot of junk in the fuel, or perhaps some bacteria growing in it.

If he parks the truck for long times, then completely fill the truck with fuel. More important, get some fuel additives to kill the bacteria and prolong the fuel life and add this as you are filling the truck, say 1/4 full, then add the stuff, and continue to fill with fuel, to mix it all together.

Worst thing to do to a truck is leave the tank 1/2 full in a humid part of the country for several months. Each day the air in the tank expands as it warms up, then contracts at night, drawing in more humid air, allowing moisture to enter the system.

Good luck!

Fred.

Fred.

[catfishmontana]

What does all his aftermarket gauges say is going on? He does have gauges when tuned that high and pulling that heavy, right?