We have a 96 PSD f250 4x4 zf5 with 3.55's We were pulling a 40' GN maybe 11k plus a 66 f100 on the trailer and a 90 f1504x4 ext cab, total trailer MIGHT have been 22k tops and it was 3rd gear foot through the floor the entire trip. No smoke under load, starts fine, GREAT power empty, milage has also been suffering both loaded and empty. 5-6mpg loaded and about 12 empty. Help No codes,
Thanks,
Dustin

 

Well, lets start with this... what do you have for mods?? Down-pipe, Intake, Gauges? Running a chip?? My truck was down on power and it turned out to be a dieing IDM, although the likelihood of that being your problem is slim. 12 Unloaded city or highway? Yea that's not a great number. More info and we can help more

-Robb

 

Robb, how did figure out your IDM was dying??

 

I had my truck into a local disel place gatting an oil leak looked into. I told them the truck felt a little low on power, and was having trouble starting when hot. They checked out mu IDM for some reason and apparently there was that green corrosion on the circuit board.. not good. Had them stick a 140 VOLT IDM in there and good as new

I was lucky, most of the time IDM either works or is dead, no intermediate stuff. I was just lucky that was the case with mine, $300 and done deal. I don't recommend people who are down on power to go buying new IDM's though because this would be the issue less than 5% of the time... I'm just going from personal experence

-Robb

 

No mods 95% stock with a luk clutch/flywheel. No, 12mpg is all hiway. It starts and runs fine hot or cold. But it will not maintain 30mph floored with any kind of a load like I said 22k isn't much. Runs Great empty but crappy milage. Changed the fuel filter 5k ago new wix air filter. I thought about fuel but It happens on both tanks they have diffrent fuel in them. odo is at 264k miles

 

This was trailer load 22k.
A 96/f250/4x4/3.55 dont even have a GCWR of 20K.
Dont have exact #, but 22k trailer is way overloaded.

Bill

 

No mods 95% stock with a luk clutch/flywheel. No, 12mpg is all hiway. It starts and runs fine hot or cold. But it will not maintain 30mph floored with any kind of a load like I said 22k isn't much. Runs Great empty but crappy milage. Changed the fuel filter 5k ago new wix air filter. I thought about fuel but It happens on both tanks they have diffrent fuel in them. odo is at 264k miles

 

That was just the trailer, truck was about another 7500lbs or so. I have pulled loads similar in wieght with a 95 PSD with an auto and it will go 65pmh no problem. This one that is a 5spd will not even do half that. The stick should pull stronger.

 

Whats the fuel pressure at have you checked it?

 

How Do I do that?

 

stock exhaust and intakes pulling 22k on 3.55's wont give you much of any power to speak of. the downpipe is horrible and at 264 the cat could be plugged.

12 mpg sucks though, is this a crew cab, standard cab, extended cab?

also at 264 have you had injector o-rings replaced ever? how does the fuel filter look when replacing it? is she black and nasty? if so you are leaking oil into the fuel system, a classic o-ring problem.

 

umm, that was weird, i just read this post not 2 minutes ago and madvans post was not there nor was dustin's post a 5:15 or any of the ones after it.....?

 

myne is a dog when you start pulling hills when hook 20k+ behind it. Buddy down the road has 4.10s and his truck flat out kills mine pulling big loads. You need to either regear or chip it.

Loaded milage sounds about the same as mine. They like there fuel when you start pushing boost. Can't explain you empty milage though I got 14 un modded and now get almost 16mpg city

 

Might check the map sensor hose from the intake, sometimes they tear or crack in such a way as to not show up until heavy load conditions, just a thought.