Home Forums Gear Hunting Trucks and Four-Wheel Drives Ford 7.3L gas engine thread

I have a request, that I bet other members would benefit from. I'm starting this thread in the hopes that owners of vehicles with the 7.3L Godzilla would share their experiences. I've already read some unbiased views in other threads related to this engine, and would really appreciate your objective views as you put miles on this engine, good, bad, or ugly. Thanks in advance!

I'll give my experiences so far, currently at 13k miles on mine. It's a 2021 F250, with the 4.30 gears. Very well equipped Lariat, 10k GVWR, payload is 2700 lbs. 2.5" lift with 37" tires.

I live in Northern Utah, anytime we go camping, fishing, or hunting, we have to pass over at least one mountain range. Empty freeway mileage ranges from 14-16 depending mostly on speed, hills don't seem to reduce mileage as much as I would have expected, when it's empty. Towing our 10k 5th wheel, with a 3k lb side by side behind that, I get 8 ish MPG. For reference, my Dad has a 2016 with a 6.7 Powerstroke, and he gets 10 MPG pulling a similar setup.

Do you feel the Deisel is worth the added 2 mpg over the gasser when you add in the diesel torque and cost of diesel?

For me, and what I do with my truck? No, I don't feel like it's worth the extra cost. I can easily go the speed limit pulling my stuff, how much faster do I need to go? Cost wasn't the deciding factor for me though, the thought of having one of the many exhaust after-treatment issues leaving me stranded on a mountain somewhere was concern #1.

I should add, my Dads truck that I mentioned does not have the 10 speed auto, so a 2020+ Powerstroke would likely get even better mileage.

If I owned a 45' toy hauler, then I would have gotten the 6.7, but I don't, and won't.

As I put in the other thread I'm on two years and 55,000 miles with mine. No complaints, and I drove nothing but diesels since 93.
Down here in the humid country I average 13-13.5 day to day empty (F-350 SRW, 3.73 gears). Pure highway empty I can get between 14 and 15. When I travel to NM, CO etc it does a little better.

Light pulling (16' bumper pull lightly loaded or 2 horse bumper pull) I'll average 11 or so. Heavy loaded 20k gross and up I'll average around 8.5- 9. My last powerstroke only did marginally better than that.

Bill

That's pretty good fuel mileage considering.

My 7.3 diesels numbers run about the same.

Following. Would like to see the 7.3 in Ford Transit. Prefer durable and simple engines, like the old Triton 6.8 V10 in E350.

I need a van for business use and am also interested in the 7.3 for the Transit. Would it fit that engine compartment?

My guess is it is possible. Push rod engine is fairly compact. The 7.3 is offered in E350 cutaway chassis.

What speed are you driving on the highway? Our Interstate speed limit is 75, and 80 in both MT and SD. I typically just set the cruise 3-5 over. IIRC at least one section of TX Interstate is 85MPH speed limit. If I could have a 7.3L gas 3/4 ton crew running empty @ 80MPH getting 14-15 I'd be as pleased as can be. I'm suspecting 11ish MPG @ that speed is probably a more reasonable expectation.

Running empty, do the 3.73 gears get any better mileage than 4.30? I never pull heavy enough to need 4.30. I currently have 3.73 in my Dodge and it's plenty powerful enough.

It's what they've done to current diesels that has a lot of old time cattlemen and farmers going back to gassers.

A good friend, who's in the cattle business, bought a new 4 door Dodge diesel. Dash lights kept coming on, causing him to take it back to dealer on multiple occasions. Finally, one day, it "lit up like a Christmas tree" and shut down. He had it towed and I'm sure used the Lemon Law to get rid of it.

He then bought a 4 door Ford F-350 4 door with the 7.3 gas engine, put his fancy aluminum bed on it. He says it gives him around 13 mpg or so, but doesn't leave him in the field. It pulls almost as good as a diesel.

Now, the older diesels were great. But govt regs got worse and worse until new diesels are less than ideal.

I would buy an older, low mileage, pre DEP diesel in good shape, or get a gasser. Gas engines are generally less expensive to maintain. Just price starters for gas and diesel engines,

DF

I drive I-35 almost every day at some point. Speed limit is 75, and between that and 80 is what I usually run. No, 11 mpg is not what I get at that speed.
With the 10 speed transmission I'm still below 2000 rpms at 80 mph.



Bill

Dirtfarmer,

The older 7.3 powerstroke trucks easily puts over 100 ft lbs more torque to the wheels, over the 7.3 gas engine. But the gas engine, puts down more horsepower.

The ride quality of the 7.3 gasser is much nicer, than the leaf sprung 7.3.

With that said, id much rather have the gasser over the 7.3 powerstroke. The 7.3 powerstroke will never cold-start as easy as a 7.3 gasser. In below zero weather in interior Alaska, any 6bt or 7.3 is pure stupidity........

mainer, if I remember right, the old 7.3 at its highest torque rating (2003) was just barely over 500 ft lbs,. The 7.3 gas is 475 ft lbs

Ran mine over the dyno, and was putting 590 ft lbs of torque @ 2900 rpms, to rear wheels.

The 7.3 gasser in stock form, guys are seeing between 380-410 ft lbs of torque at the rear wheels.

Nothing special: rebuilt turbo with a $500 kit kc turbos, s&b filter and housing and a boost fooler.

Still feels sluggish, towing a one ton truck up hills, so may have to spend another $340 on a hydra tuner

Gotcha, I never ran the 03' we had on a dyno, nor the 03' 7.3 powerstroke we still have at work. Having driven both I'm just going by feel and experience
from having driven both and the 7.3 gasser I'm running now.

The first Gen Duramax, which is quite a bit more powerful than the 7.3 Powerstroke, only put down ~200 hp/ ~400 tq at the wheels. Like you said, the 7.3 gas puts around ~360 hp/ ~410 tq. Combine that with the 10 speed auto, the 7.3 gas will out tow all those early diesels, up to and including most 6.0 Powerstrokes. The F350 7.3 gas with 4.30 gears is rated up to 20,200 5th wheel/gooseneck in a Crew Cab 4x4.

I've owned a 7.3 Powerstroke, and currently a 7.3 gas. my new gas truck will out tow my old diesel easily, and much more comfortably also.

I've only had mine for 6 weeks and 2000 miles. Mine has the 3.55 rear end. 1st gear in the 10 speed is lower than the 1st gear in the 6 speed trans. I am not towing over 10k so I did not feel the need to go with 4:30 rear end. I had the 4:30 in a 4 speed V10 truck. This truck moves my trailer way easier at all speeds with less rpms.

Our freeway limit is 80. In my Dodge Cummins, the mileage isn't bad at 75 but at 80, the gas gauge needle moves faster than the speedometer needle.