Moobesor

With all the mods I have on my truck, is the MPG digital monitor accurate? I made a 8 hour road trip, both highway and street (80% highway) and had 22.4 MPG.

If I attempted even better gains (coasting and lightly apply throttle at every stop, intersection, et cetera) I could have probably done better.

Seems unrealistic, but at the same time (hopefully) reassuring.

MikeyB

I wouldn't trust it. Always hand calculate to at least verify that the overhead is correct. My 'Guess-O-Meter' is about 2-3 mpg off. And that was back when the truck was stock.

MikeyB

rip 112

Mikey is right, mine also is about 2mpg off. I see about 19.5-20mpg and the readout says 22.9.

glocklove

Yea mine is off about 2 mpg also, I hand cal an avg of 17 around town and my over head reads 19.5 to 19.7.

dale29

mine's off by 3-4, the longer the trip the further off it gets.

Raspy

Mine averages about 1.75 MPG high on it's reading. You have to correct the odometer and then hand calc for the mileage.

Mods to the truck will change the accuracy because the computer is being fooled by the mods. For instance, timing might improve the mileage but the computer does not know the timing was changed. Larger nozzles will give more power and then lead to a lighter throttle position, but the computer does not know about them and will be looking at the throttle position. So it would think the mileage was higher.

Just hand calc (with a corrected odo) and get a feeling for the accuracy. Do it as accurately as you can with a completely topped off tank and over a lot of miles. Preferably several tanks. Fuel gauge guesses mean nothing, fill it to the brim and record the quantity.

one54ton

Mine says im getting 24 mpg going 75 mph with my mods

chipmonk

cool- you must be a great driver. i had a 2nd gen that said that i was getting 30!

Big Blue24

I've had my overhead reading as high as 32 mpg after several miles at 60 mph with everything set to kill.

In my experience, the higher you set your programing or fueling box, the more inaccurate the overhead becomes.

Nsomniac05

In my experience, with crazy larry, at 65 mph on a consistent trip, its pretty accurate, but if you accelerate past 65 the readout gets better while the mileage obviously gets worse.
ie: my 2500mi cross country trip, at 65 mph for a whole tank, it said 24 and i got 23 and some change, but at 70, 75, and 80, it went up accordingly, and said something like 29 at 80 mph whereas my handcalc was less than 20.

and also i would say with only stage 2 sticks and taller than stock tires, if you drive for the purpose of economy, you are probably netting upwards of 20-21. I just dont know how much the dual cp3 hurt you, thats the only thing i think that wouldnt work for both HP and fuel mileage.

Neight

Man I don't understand how you guys are getting the mileage you are, my over head says 13.5 and when hand calculated I am getting 16-17.

EDR

I have the REVO #3 setup on my truck and the overhead is usually 2-3 mpg higher than my hand calculated numbers.

I also noticed that my overhead MPG reading went up at higher speeds (75 +) and down at lower speeds (60-65). I should have known better . . .

My hand calculated numbers going from Vegas to Denver, full cab and full bed, at 75-80 mph came back at 16.23 mpg.

Mega07

I wish mine were accurate, Id settle for whats on it which is usually 15-16.5, but unfortunately my truck both stock and modded has had crappy mileage. The best I have gotten in the city has been high 15s, typically it is 13.3-14.5. Highway has been no better than 18 and that was once....Kind of frustrating since I bought a diesel to get better fuel mileage, I mean ya my truck is modded now but my mileage hasnt changed hardly at all from stock to modded. I just wish I was getting these 20+ mpg like a lot of you are...