Hot Rod Forum banner

Ford 7.3 idi diesel

20K views 21 replies 10 participants last post by  cliff tate 
#1 ·
How much mpg could i expect from an f350 with the 7.3 idi? I hear anywhere from 14-22. I will be putting a new muffler and cold air intake on it asap if i decide to buy the truck so im hoping that will be good for another couple mpgs. It has the auto tranny btw.
 
#2 ·
We averaged 15.5 with a 99 F-350 dualie with a 7.3 Powerstroke and 6 speed manual. As an uneducated guess I'd say the idi would be somewhere in that ballpark (maybe 14?). I'm not convinced that people with newer full sized turbo-diesel pickups are averaging 20+ mpg, let alone those that claim 25...
 
#3 ·
Ehh i was hoping to get at least 18. U think if i drive easy, put the intake and exhaust on, and keep the fuel filters and such clean i could hit that mark? My dad's dodge dually with a 12 valve cummins gets 20 average so i know its not unheard of.
 
#4 ·
bigdog7373 said:
Ehh i was hoping to get at least 18. U think if i drive easy, put the intake and exhaust on, and keep the fuel filters and such clean i could hit that mark? My dad's dodge dually with a 12 valve cummins gets 20 average so i know its not unheard of.
Couldn't tell you. My only experience was with a Powerstroke in a dualie,. The dualies add some weight as well as more rolling resistance compared to a single rear wheel.
 
#6 ·
bigdog7373 said:
Is there any other things i could do to get it closer to 20?
Ayuh,... Skip the Idi, 'n go with the Power Stroke....

My old Idi, in a F250 used to average 15/ 16mpg...
with a C6 tranny...
My 96 Power Stroke averages 17/ 18mpg...
It'll tickle 20mpg runnin' empty, haulin' nothin'....
with the E4OD tranny...
 
#7 ·
I am suprised anyone gets over twelve. Of course you would get better mileage on the highway and a six speed or a gear vendors unit would help in that area.
Pumps can be adjusted as well to help in the mpg area. I dont remember the intimacies of that, but you pull a cover and there is a screw that you can adjust to ramp up or down fuel delivery to the injectors.
 
#8 ·
bondo said:
Ayuh,... Skip the Idi, 'n go with the Power Stroke....

My old Idi, in a F250 used to average 15/ 16mpg...
with a C6 tranny...
My 96 Power Stroke averages 17/ 18mpg...
It'll tickle 20mpg runnin' empty, haulin' nothin'....
with the E4OD tranny...
I cant afford a power stroke, cummins, duramax, any of those. The idi is the best i can do and its not too far of a drive. I think i might buy it if checks out ok.
 
#9 ·
I am personally driving a 1992 f250 4x4 E4od extended cab long box right now. Average driving (summer) is 15-16. It has 286,xxx miles on it. I turned up the pump a quarter turn to make a bit more power due to it getting tired over the years. The last one I had was a 92 f250 standard cab long box that had the banks Sidewinder Turbo kit on it. More power and 20 MPG (when I could keep my foot out of it or not towing)! Diesels only get good mileage when empty! Loaded, they do about the same as a Gasser. If this didn't help ya post what else ya need. Glad to help!
 
#10 ·
CJ_1080 said:
I am personally driving a 1992 f250 4x4 E4od extended cab long box right now. Average driving (summer) is 15-16. It has 286,xxx miles on it. I turned up the pump a quarter turn to make a bit more power due to it getting tired over the years. The last one I had was a 92 f250 standard cab long box that had the banks Sidewinder Turbo kit on it. More power and 20 MPG (when I could keep my foot out of it or not towing)! Diesels only get good mileage when empty! Loaded, they do about the same as a Gasser. If this didn't help ya post what else ya need. Glad to help!
Thanks, this is exactly what i was looking for. Im assuming the dually will get 1-2 mpg less but the intake and exhaust should make up for it. If the truck is in good shape il most likely buy it. Im not gonna use it for towing really anyway. How much did that turbo kit run you?
 
#12 ·
I had a 1 ton single wheel with a 5 speed that got around 12mpg. When it was loaded it was like 8-10 and it was only 2wd. I wouldn't want an idi again; hold out for a powerstroke. Unless you are an experienced diesel tech and have the tools to work on this old iron I would pass it up.I mean think about it, gotta put a turbo on it and then baby it to get the mileage you want out of it?! Remember it is more than just bolting a turbo on to get more power. Also, if the injectors or pump is weak you will get less mpg with a turbo kit. Not to mention possible engine damage. Now, I am a little biased since I dred working on these motors because I prefer the DT570 or a cummings(newer motors in big trucks). I only see these little squirts in tow trucks and pickups and such. However, I will say they are durable and quiet smooth running little motors(powerstroke is even better); but definetely NOT my first,second, or third choice. Lastly, parts are getting harder to come by and techs that can work on em are getting thin as well. For instance, just an overhaul on the pump is gonna cost 1,000 give or take. The most common fault is the lift pump that runs off of the camshaft; that booger is about 100 smackers. Just some food for thought. :)
 
#13 ·
Are you kidding me?!

I'm sorry, but you guys are absolute twits recommending someone to go with the modern crap over the older/simpler/better.
I have the 'tractor engine' simple 7.3 idi in my '92 manual 4WD F-350 - i haul stuff all the time on windy steep roads under 1k ft altitude and it gets 17 to 18 mpg without even trying/'im often pushing it up the hills. This is amazing for a 1 ton truck IMHO; the damn thing weighs 10,500+ lbs EMPTY. And it is bone stock, non turbo. Then add the value points of: no smog (CA-pre'98), cheap parts (glow plugs/injectors etc) that are simple to replace, NO COMPUTER...and its pretty self evident. Maybe i've just got an exceptional example that rolled off the assembly line, but I don't think it's that simple. To me, simplicity trumps complexity every time. And when I talk to late-model Duramax owners that are fighting to get anything over 15-16, I don't understand why anyone would want a modern 'smogged-out' computerized diesel; it sort of defeats the purpose. And maybe some of you guys need to drive these trucks like trucks, not sports cars. Typical misuse of power: guys with hot trucks thrash their power & drivetrains, & guys with hot cars end up wrapping themselves around trees, or worse...but i digress. KEEP IT SIMPLE, PEOPLE.
 
#14 ·
Those trucks are good we have a 94 on the farm it get 12-14 city and 17-18 high way and @ old school diesel your gvw isn't your weight our 94 4 door dually tips the scales at around 7800lbs my 99 f350 with welder, air compressor, tools and cutting torches and tanks weighs 10,100 lbs. I agree on the cheap parts though I just replaced two injectors for $50 a piece my 99 was 120 for 1 injector
 
#17 ·
I have a 1999 power stroke f-350 4x4.I get up to 24 mph on the highway.Thats using a Canadian gallon which 160 ounces compared to american gallon at 128 ounces.To get that mileage I need to keep the speed at 110 kph or less.(about 65 mph) I have the 4 speed auto in my truck. I "usually" get 22/Canadian gallon and drive at or above posted speed limits staying with in traffic. The 24 miles per Canadian gallon was achieved this year returning from a fishing trip in Clinton BC and I traveled about 500 k.m. (300 miles) 40% or more of that was in the mountains,not just flat ground.The truck weighs just under 7,000 pounds.
I actually was gas mileage racing a friend with a Jimmy 4.3. He used more fuel but he also beat me home by 15 minutes
 
#19 ·
I know monster -just am prone to exagg at times; gvw is the
weight they tax you in reg even when you're not carrying it :)
I have a "26,000 lb dump truck (Cat engine), & of course it's taxed
as if it's grossed at 26k every time it's on the road.
If you know, what would you recommend as a turbo system?
I'm buying some land that's at altitude & am thinking the
normally aspirated will be a bit weak at 5-7k feet.
 
#21 ·
You could could look for banks or ats or source down the 93-94 idi turbo kits that came on some of the trucks factory although remember these truck have much higher C.R so I wouldn't boost it more 12-15 lbs.

@ bigdog it always gets me these dang revived threads are like freaken zombies attacking
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top