7.3 Gas Fuel Economy: What Is The MPG On a 7.3 Godzilla?
Trip meters do not always tell the truth. They may be set to give you a little encouragement. Some owners reported that their trip meters registered a higher mpg than the results they go when they did their own calculations. MPG is not written in stone however and it will vary.
This is going to depend on how you drive, where you drive, and if you are towing or not. According to the spec sheets, do not expect more than 11 to 12 mpg when empty. When towing, your mpg should go to about half of those figures. You may get 8 under ideal conditions.
To learn more about this engine and its mpg rating, just continue to read our article. It has the information you need to help you decide if you want to buy a truck with this motor or not. Take a few minutes and examine the results.
Ford 7.3 Godzilla Fuel Economy
This is a 920-pound motor that produces 430 hp at 5500 RPM and 475 lb-ft of torque at 4000 RPM. Do not expect it to compete with an economy car. Some owners are speculating that the 10-speed transmission is going to help boost the fuel economy of this motor.
They are saying that they should expect around 18 mpg. Others are not so over-enthusiastic and state maybe 16 at best. Owners have reported getting between 12 and 14.9 mpg when empty and driving on flat roads.
But your fuel economy will vary. The reason it will vary will be due to road conditions, your driving habits, weather, and if you are towing or not. One owner reported a high of 18.5 at 70 miles per hour and 19.5 at 55 mph.
However, this test was only done over 10 miles and is not an accurate rating to follow. He also reported 11.5 when towing and stated that the mg increased from when it was new. We cannot prove or disprove his claims but this would be an isolated incident if true.
Your results will depend a lot on how you drive. Not everyone drives the same and does not expect to get great results when the rating is set very low by the company that made the engine.
F350 7.3 Gas Mpg
We checked two model years one from 2021 and one from 2020 and the results were not as impressive as reported by that one owner. The mpg was down around 14 mpg for the 2021 and 10.8 for the 2020.
Most owners that we came across in our research stated that they got around the 14 mpg mark with some a little bit lower and some a little bit higher. There were the odd few who reported astronomical results, 18 or 20 mpg, but those were not accepted by other owners.
One owner drove his truck from Vermont to New Hampshire and he reported that he got 33 mpg on the way there and 16 on the way back. The difference was attributed to the fact that the trip to NH was almost all downhill.
Road conditions will play a role in your results but the company rated the engine at 12 mpg approx so if you get better than that, then you are doing well. Also, the rear end will probably influence how many miles you get per gallon of fuel.
The 4.10 will get lower fuel mileage than the 3.73.
7.3 Godzilla Supercharger Mpg
From the owners that have a supercharged model, the prospects do not look that good. The figures they quoted were under 10 for the most part with one saying it was over 10 (11 mpg), when he drove his rig.
Even with the supercharger installed, the mpg is going to depend on the weight of the vehicle and if it is towing a trailer or not. The exact figure one test produced was 8.8 when towing. The owners think that is a respectable result.
But for the most part, any website talking about the supercharger models focused on the increase in horsepower and torque. They did not crunch any numbers to get a rating for mpg.
The most you can hope for will be about 16 to 18 mpg on the highway, 11 to 12, mpg in the city, and below 10 when towing.
7.3 Godzilla Mpg Improvement
If you are not satisfied with the results you are getting right now, there are things you can do to improve those results. Some of the suggestions included going to lighter wheels, skinnier tires, and better driving habits.
You can get a 5-star tune that should boost your mpg rating a little bit but it has been reported that the boost is not significant. Or you can change your fuel, going from an 87octane with ethanol to an 87 octane without ethanol.
The problem is that you cannot do much without voiding the warranty if the truck is new. You have to be careful when you make improvements as manufacturers do look for excuses to not spend any money on repairs.
Also, you can cut your speed. The 7.3 is known to produce very low mpg once you go beyond 70 mph. The below-70 mpg seems to be consistent around the 12 to 14 mpg mark when empty and driving highway miles.
Some Final Words
While you may need the power to tow your trailers or other heavy loads don’t look for mpg performance. You are not going to get it with such powerful engines as the 7.3. You will get low fuel mileage no matter what you do.
Those owners reporting very great results may be miscalculating their data. Or they bought a model whose 7.3. was the best of the lot. Those good results are not the norm but a rarity if they are true at all.
Do your own calculations to see what you get and not rely on what others claim.
