Fuel Economy in 7.3 IDI vs. Powerstroke
Senior User
Joined: Jul 2009
Posts: 223
Likes: 0
From: southeast texas
i used waste vegetable oil in my truck for about 80 gallons worth mixed 50/50 with deisel and it rode smoother and quieter but my mpg's didnt change much...still anywhere from 13-15 average hwy/city depending on how i drove that week. had to change out my fuel filter though...
Elder User
Joined: Jan 2008
Posts: 837
Likes: 0
From: Newark, Delaware
I had a 1990 F-250 7.3 IDI reg cab long bed and I got about 14-15 with that. The only mods were dual straight pipes and the air intake "soup bowl" delete. I now have 2002 PSD (in my sig.) and I get about 16-18 with that depending on how I'm driving.
New User
Joined: Aug 2009
Posts: 2
Likes: 0
Mileage
7.3 2001, keep it below 1900 RPM if you want good mileage. Boost is your friend but only below 1900 rpm. If you have a manual tranny this is easy. However the auto is is a bit persistant when it comes to downshifting. This is where i bag on the maketing people at ford. They decided that a diesel should or could perform like a gasser. results, past half throttle, and before the turbo spools up the tranny down shifts and off you go in a pile of dollar bills. to bad cause it is a really god system otherwise.
3.55 gears and manual tranny good for mileage
3.73 gears and an auto good for mama
pick one.
3.55 gears and manual tranny good for mileage
3.73 gears and an auto good for mama
pick one.
Elder User
Joined: Jun 2009
Posts: 999
Likes: 0
From: Easley, SC 29640
After driving diesel pickups (Cummins, PSD, Duramax) for 25 years I have concluded that I have NEVER seen so much horse manure written about fuel mileage as in this thread. Good grief, a PSD pulling 8000 pound trailers getting 25 MPG. That is hysterical. I went over to look at similar threads on Duramax and Cummins motors and found, no surprise, an equal volume of horse droppings.
There isn't a "powerchip" made that does ANYTHING but change the balance of power output, fuel economy, and engine longevity. Can you get better mileage? Sure...but you'll pay for it in engine life. More power? Sure... But there is a trade-off for every little thing you do. If you do not believe it, you are simply deluding yourself. Go ahead...have fun with that. Just make sure you admit it in the ad when you sell the truck because the rest of us who DO know what we're doing want to avoid your truck.
If you believe that anyone on earth knows more about your PSD than Ford or more about your Duramax than GM, you are making an expensive mistake. Do you really think that some wrench shop down in Alabama knows PSD's better than Ford? Then go buy some STP...or Motor Honey...or one of those miracle air cleaners from K&N...but leave your engine alone so when you sell it the next guy doesn't get hosed by your ignorance or foolishness.
Let's have a show of hands: How many people know how many four wheel drive dynomometers there are in Detroit...mounted in anechoic sound chambers...with vibration sensors, full EGT analysis, and full environmental controls? Ever been there when they torture a truck to death? Been to the proving grounds? I thought so.
Too many of you guys have no respect for automotive engineers because you have no idea how vehicles are engineered and built. Too many think that the OEMs are in some vast conspiracy to defraud you and make you burn more fuel because they are in cahoots with Amoco or design your car parts to fail eight minutes and fifty-nine seconds after your warranty expires. Too many think that some nitwit at K&N knows more about air filtration than Ford or Chrysler. Too many scrap a perfectly functioning exhaust system for some cobbled up pile of junk from Flowmaster or, worse, straight pipes. I guess there is a sucker born every minute but my advise to you is DON'T BE ONE OF THEM.
If this makes you angry, that is OK with me. But for the sensible readers out there just looking for good, reliable advise and information, take my advise: Read your owners manual. Follow their guideance. Live long and prosper. And don't imagine for one moment that you'll EVER see 25MPG in a one-ton dually unless it's on a flatbed.
There isn't a "powerchip" made that does ANYTHING but change the balance of power output, fuel economy, and engine longevity. Can you get better mileage? Sure...but you'll pay for it in engine life. More power? Sure... But there is a trade-off for every little thing you do. If you do not believe it, you are simply deluding yourself. Go ahead...have fun with that. Just make sure you admit it in the ad when you sell the truck because the rest of us who DO know what we're doing want to avoid your truck.
If you believe that anyone on earth knows more about your PSD than Ford or more about your Duramax than GM, you are making an expensive mistake. Do you really think that some wrench shop down in Alabama knows PSD's better than Ford? Then go buy some STP...or Motor Honey...or one of those miracle air cleaners from K&N...but leave your engine alone so when you sell it the next guy doesn't get hosed by your ignorance or foolishness.
Let's have a show of hands: How many people know how many four wheel drive dynomometers there are in Detroit...mounted in anechoic sound chambers...with vibration sensors, full EGT analysis, and full environmental controls? Ever been there when they torture a truck to death? Been to the proving grounds? I thought so.
Too many of you guys have no respect for automotive engineers because you have no idea how vehicles are engineered and built. Too many think that the OEMs are in some vast conspiracy to defraud you and make you burn more fuel because they are in cahoots with Amoco or design your car parts to fail eight minutes and fifty-nine seconds after your warranty expires. Too many think that some nitwit at K&N knows more about air filtration than Ford or Chrysler. Too many scrap a perfectly functioning exhaust system for some cobbled up pile of junk from Flowmaster or, worse, straight pipes. I guess there is a sucker born every minute but my advise to you is DON'T BE ONE OF THEM.
If this makes you angry, that is OK with me. But for the sensible readers out there just looking for good, reliable advise and information, take my advise: Read your owners manual. Follow their guideance. Live long and prosper. And don't imagine for one moment that you'll EVER see 25MPG in a one-ton dually unless it's on a flatbed.
New Brother...Thems almost fightin words you're speakin thar...hehehehe...we love our trucks, and like to make 'em do better...if you think the OEM folks ain't out to engineer some key breakage points to get a little more loot from us, i would say you would be the delusional person here....case in point, and back me up brothers...the OEM Ford "non-serviceable" HPOP plug....myself included, how many of us heard that we HAD to buy a brand spanking new HPOP because a threaded plug was leaking and were assisted by our FTE brothers with PDF's, part numbers, instructions, and "Alabama wrench turners" driving from god knows where to come help us get dirty and make a needed repair so our truck didn't fill every driveway we stopped at with an OPEC puddle...if you think for even a brief moment that some old a$$ Ford engineer didn't think ahead that if there was a threaded plug strategically placed on the underside of the HPOP, having really no particularly good reason for there even being a plug there, when the o-ring rotted out due to the detergents added to our oil, that we would HAVE to replace it at an inflated price so they could either get us to pay $800 for a replacement, or might just be stupid enough to trade up for a new one, then you have NEVER been to a Ford Service Department, or Stealership....have a great day...if you don't agree with our country a$$es trying to help each other save some loot and some aggrivation...don't go away mad....JUST GO AWAY
Sorry for the rant fellow brothers....i love my truck...the sound, the smoke, the stares i get from passerbys when they have to stop their conversation cause i hog-legged by 'em....hahahahaha...
By the way....i get 18 mpg empty, and 15 pulling @ 9k....not sure the rear end gearing, but it gets the job(s) done.....
New User
Joined: Aug 2009
Posts: 2
Likes: 0
pardon my smell
I love my truck. this is my second super duty powerstroke. the first one saved my life when an idddddiot in a bowtie rearendded me at a stoplight doin better than 65mph. nothin but ford heavy metal could have saved me that day.
but as for the engine:
i don't know about the HPOP plug mabe you could fill me in befor I have the same problem.
yes the fuel / water draian valve (plastic!) sucks, I blame accountants
the air intake and filter could be better, I blame the US gov.
and the porosity that endlessly leeks fuel from the block, hencha el Mexico
but still the best damn engine in a pick-up truck ever.
I just wish i could find some help with the transmission programing.
P.S. 250 rear wheel hp stock, thats good enough for me.
65%of all drivers think they're better than average
i'll stay with average and keep it under 65 when I'm grossed out (20,000lbs) and playing with 9% grades.
mine ain't a toy it's a Truck.
but as for the engine:
i don't know about the HPOP plug mabe you could fill me in befor I have the same problem.
yes the fuel / water draian valve (plastic!) sucks, I blame accountants
the air intake and filter could be better, I blame the US gov.
and the porosity that endlessly leeks fuel from the block, hencha el Mexico
but still the best damn engine in a pick-up truck ever.
I just wish i could find some help with the transmission programing.
P.S. 250 rear wheel hp stock, thats good enough for me.
65%of all drivers think they're better than average
i'll stay with average and keep it under 65 when I'm grossed out (20,000lbs) and playing with 9% grades.
mine ain't a toy it's a Truck.
Junior User
Joined: Aug 2009
Posts: 70
Likes: 0
From: Mobile
i read an article in an old popular science mag that compared tailgate up vs. tailgate down vs. tailgate gone. ironically our assumed logic is backwards as the tailgate up scored highest efficiency followed by tailgate down followed by tailgate gone. they were tested in a wind tunnel and im tired of typing "tailgate"...
Senior User
Joined: Apr 2009
Posts: 295
Likes: 0
From: Johnstown PA
I travel 375 round trip to work with most of it being fairly flat, and highway. If I am good, and keep the RPMs just at or under 2000 (65 mph occasionally 70) I seem to do pretty good. Hand calculated I have gotten 22 on several occasions when I fill up, get right on the highway and fill up as soon as I get to work. But I would have to say my average is more like 19-20. I figure it out just about every time I fill up, and dont see 22 as much as I would like.
Around town, I would guess 16 or so, dont get much just around town driving between fill ups.
Around town, I would guess 16 or so, dont get much just around town driving between fill ups.
Freshman User
Joined: Apr 2009
Posts: 28
Likes: 0
From: Fayetteville NC
New Brother...Thems almost fightin words you're speakin thar...hehehehe...we love our trucks, and like to make 'em do better...if you think the OEM folks ain't out to engineer some key breakage points to get a little more loot from us, i would say you would be the delusional person here....case in point, and back me up brothers...the OEM Ford "non-serviceable" HPOP plug....myself included, how many of us heard that we HAD to buy a brand spanking new HPOP because a threaded plug was leaking and were assisted by our FTE brothers with PDF's, part numbers, instructions, and "Alabama wrench turners" driving from god knows where to come help us get dirty and make a needed repair so our truck didn't fill every driveway we stopped at with an OPEC puddle...if you think for even a brief moment that some old a$$ Ford engineer didn't think ahead that if there was a threaded plug strategically placed on the underside of the HPOP, having really no particularly good reason for there even being a plug there, when the o-ring rotted out due to the detergents added to our oil, that we would HAVE to replace it at an inflated price so they could either get us to pay $800 for a replacement, or might just be stupid enough to trade up for a new one, then you have NEVER been to a Ford Service Department, or Stealership....have a great day...if you don't agree with our country a$$es trying to help each other save some loot and some aggrivation...don't go away mad....JUST GO AWAY
Sorry for the rant fellow brothers....i love my truck...the sound, the smoke, the stares i get from passerbys when they have to stop their conversation cause i hog-legged by 'em....hahahahaha...
By the way....i get 18 mpg empty, and 15 pulling @ 9k....not sure the rear end gearing, but it gets the job(s) done.....
Sorry for the rant fellow brothers....i love my truck...the sound, the smoke, the stares i get from passerbys when they have to stop their conversation cause i hog-legged by 'em....hahahahaha...
By the way....i get 18 mpg empty, and 15 pulling @ 9k....not sure the rear end gearing, but it gets the job(s) done.....
Junior User
Joined: Apr 2008
Posts: 91
Likes: 0
From: Vashon, WA
The answer of course is = Engineers do not make these decisions, there are made by regulators and corporate managers. Regulators are trying to do right (as far as they think they know right to be, but let's not go there) and the bean counters trying to give us a competatively priced truck (ie: where can they cut corners and still provide a satisfactory product for the majority of customers) while still making a profit so they can provide us another truck in 5 years.
Decent design, you bet. Can it be improved? double down on that one. You can get better milage and better performance and longevity by improving efficiency period.
Rant concluded.
Almost forgot : My 85 6.9L IDI 4x4 4 speed 6000lb empty gets about 18 around town. Been on the freeway once or twice in the last nine years but it revs way to high at 55mph w/out OD. The island I live on has no freeways so I just don't take it off island and do not know what it gets for mileage on a freeways.
2000 sc 7.3 4x4 3.73 auto 8000lb empty gets about 13.5 around town towing 7k about half the time. When doing mixed freeway and town I get somewhere around 17.5. Never had it on a long empty freeway trip, only towing 7k and loaded (18k on scales) where it gets about 13.5 mpg.
Freshman User
Joined: Apr 2010
Posts: 41
Likes: 0
From: texas
this is a long post, i got interested in this one cause i get terrible gas milage its between 10 -12 mpg. i did however get the rpms i have a 94.5 7.3 turbo diesel dually monster, i love it . rpms are at 50 mph 1800, at 70 there 2600. at every 5 miles between i see about a 200 rpm increase. ive been told my truck is sick, i am looking into this site to improve that. i will use some fair judgment but think some mods are practical.
Senior User
Joined: Apr 2005
Posts: 204
Likes: 1
From: Gillette, wy
I just drove from gillette, wy to denver and back which is about 700 miles. 75 mph i was getting 12 mpg, 70 was 14 mpg, 64 was 19 mpg(1850-1900rpm). The person that had my truck before me put 4.30 gears in it. It had 35" tires on it too. Thinking about putting 4.10's in it.
Fleet Mechanic
Joined: Jul 2010
Posts: 1,753
Likes: 34
From: Los Angeles, Ca.
'88 IDI van; automatic, 3.54 gears(I think), no OD. Just did 18.5 with about 60% street driving. I was trying to drive nicely because the price of diesel is crazy and I'm not used to buying it, ran out of waste oil....uggghhh.