Hmm, okay. I guess the reports I've heard of great fuel economy were greatly exaggerated. Damned liars. I guess there just aint no such animal as a 20 mpg power stroke. With no first hand experience, I retract my statement. When I bought my 6.0, I thought I was getting a 7.3 (not knowing at the time that they changed engines for smog requirements), mainly because of the reputation of the 7.3. That was one of the reasons I bought the 7.3 was because of my apparently misguided knowledge of 20 mpg powerstroke... I suppose my disappointment with 16 mpg was unwarranted. Thanks for clearing that up.

 

You can get 20 mpg as I've gotten 21 on occasion. That was empty on a 300 mile trip with the cruise set every chance I could. I could never get that on short trips or around town. My normal average is 13 to 15. If the engine never gets up to full operating temps it's probably in the single digits. ie; grocery getting. Your best mpg mod is a light right foot.

 

I can easily get 20+ on the highway. It's been forever ago, but I think the best I ever got with a 99 7.3 was 19.

Josh

 

'99 was like the '08 model year, it was a looooooong one. As far as I know there were three different smog/intake configurations that came to CA for MY '99 7.3s (there may be other differences). Mine was an early build that had the small intake and a cat converter, then they put on a large intake w/o a kitty and then Large intake with cat converter (I may have those last two backwards).

Had a friend, lucky ******* , that had the large intake no kitty model with the good ol' CA Emissions sticker right there big and bold: No Catalyst, under the hood And no, he still won't sell that truck...

Mine was a SC/LB 4x4 w/ 3.73s just like our current truck, I tried out a Super Chips Microtuner and ran that on the 50HP tow tune and it really made the trans crisper and woke up ol' sleepy under the hood. Still, tuned or not my best fwy trip at 65MPH was 16MPG, that was with three dirtbikes in the back and three guys in the cab, so a little wind resistance maybe.

Don't get me wrong, I did love and still do love the 7.3s -- they're tough sob's. But I'll never forget also taking the '99 into a dealer and my first drive in a 6.0oooooooh-my-gawd!! Got back in the 7.3 and even with the 50hp tune it felt like I had a marsh mellow on the go pedal.

I had a hand calc'd fwy run down to San Diego in this current truck and kept it between 70 and 75, over the grapevine and all and it was 18.8mpg rolling into SD. Coming home with a new Rhino (with a roof) in the back (wind catcher) got 15.5mpg.

Buttt... I've also seen 7's on a hell-fire run up the sierras with friends with all Diesels, Chevy, Dodge & us, weighing a tad under 18K with the brick-like camper aerodynamics Yeah, we took our time. right

We didn't drive too crazy, but I don't remember anything passing us either

 

Mine was one of the earliest 99 Superdutys, but it did not have a kitty. I have no idea about the intake.

I think the 1999 F250 truck I had was built February or March 1998.

I also had a 2001 F350 work truck. I hated that truck...

For a short time I also had a 2003 F550 with a 7.3 before I started using my own 2005 F250 for work.

Out of the 3 I liked the 99 the best, the 2001 sucked ***** and the F550 was alright, but a biotch to start cold, same as the 2001.

Not a fan of repairing the leaking oil coolers on those either.

Josh

 

Wait, so you are saying that 7.3 owners will exaggerate their fuel economy numbers?

 

I suppose you're right Chris. The old, "IT'S THE BEST OF THE BEST 'CAUSE I BOUGHT ONE AND I WANT YOU TO THINK I'M SMART" syndrome.

 

No different than the 7.3 Fan Boys forgetting the CPS debacle, the 4R100 is junk, Glow plug solenoids crap out, glow plugs suck, oil cooler leaks, oil pan rusts, ball joints (LOL) and more.

I really like the serpentine belt version that you have to drain the coolant, and remove the upper radiator hose to just change a belt.





Josh