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Gasser real world fuel economy

seven30

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87 octane, 3.73 gears, 35x12.5x20 tires. Flat area and averaging 17.6mpg with 60/40 town/highway.
I guess the next piece of info we need is how accurate are the millage displays and how much do they deviate. I tend to think they are accurate but I believe its a derived consumption based on injector duty cycle rather than direct flow meters.
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I definitely need to re gear, but since it doesn’t “hurt” anything, I’m putting it off till spring.
17.7 is fine… but if I get on it in ANY capacity to even include 2% grades etc, I’m typically down under 13.
 

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Mojave w/5.13s and 37x12.5/17. Averaged 18mpg in mixed driving with my old 37” K02s, with my new Baja Boss AT 37s it dropped to around 16.5-17mpg.

Recently drove down to Texas from NJ averaged around 14.5-15mpg highway, around town I’m lucky to get 13mpg.
 

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I guess the next piece of info we need is how accurate are the millage displays and how much do they deviate. I tend to think they are accurate but I believe its a derived consumption based on injector duty cycle rather than direct flow meters.
Could be like the EPA calculates it - what comes out the tail pipe. Can't say for sure.
In any case, mine has proven to be really close, depending.
When I towed the cluster said 13.8 - the app on my phone said 13.9
Other times my display has shown something like 20.4 and the phone app said 20.0
Over several tanks it works out pretty even, or close enough to say the truck is pretty darned accurate.
The reason manual calculations or apps will differ from the cluster display is when you fill up unless you park in exactly the same spot, tires in the same place, use the same pump, pump at the same speed and stop the nozzle with exactly the same fuel in the tank - it's going to be different than last time you "filled". You may be putting anywhere from .25 to 1.0 gallons more or less in than last time you filled.

I've also checked my truck's odometer and speedometer against my phone and a real GPS (Garmin) I found the speed aligned perfectly and when I drove 17+ miles after setting things to 0, when I stopped, they all agreed to the tenth of a mile. Not bad.
 

seven30

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Could be like the EPA calculates it - what comes out the tail pipe. Can't say for sure.
In any case, mine has proven to be really close, depending.
When I towed the cluster said 13.8 - the app on my phone said 13.9
Other times my display has shown something like 20.4 and the phone app said 20.0
Over several tanks it works out pretty even, or close enough to say the truck is pretty darned accurate.
The reason manual calculations or apps will differ from the cluster display is when you fill up unless you park in exactly the same spot, tires in the same place, use the same pump, pump at the same speed and stop the nozzle with exactly the same fuel in the tank - it's going to be different than last time you "filled". You may be putting anywhere from .25 to 1.0 gallons more or less in than last time you filled.

I've also checked my truck's odometer and speedometer against my phone and a real GPS (Garmin) I found the speed aligned perfectly and when I drove 17+ miles after setting things to 0, when I stopped, they all agreed to the tenth of a mile. Not bad.
Good point on fuel. Fuel temperature has a real effect on density and the pumps just measure volume. Pumping fuel that is stored at a cold temperature should result in better mpg.

Last trip Colorado to Texas pulling empty trailer 20.4 until I hit Lubbock. Dropped to 17.8 from there to central Tx. Running 65-70 at 7K altitude and no wind its 21-22 tops. 6spd with AT tires and 15K miles.

Then I arrive and take a left into the gnarly stuff trailer and all!
 

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Just got around 12 mpg on E85, averaging low 80s.

If I behave on the highway it's more like 16 mpg at 75 mph.

35s and 4.10s.
 

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Just got around 12 mpg on E85, averaging low 80s.

If I behave on the highway it's more like 16 mpg at 75 mph.

35s and 4.10s.
E85? Oh, you have things modified.........tuned for E85...........

I filled up today - FillUp said I did 20.1 while the Jeep said it was 19.9
I had been getting a bit more but the weather has changed (Iowa's calm season is over, a lot of WIND) and colder temps.
 

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E85? Oh, you have things modified.........tuned for E85...........

I filled up today - FillUp said I did 20.1 while the Jeep said it was 19.9
I had been getting a bit more but the weather has changed (Iowa's calm season is over, a lot of WIND) and colder temps.
E85 has to be super cheap and plentiful in Iowa!

It runs silky smooth on E-85 and has great power.
 

NC4stroker

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2021 Gladiator, gasser. 950 miles on the clock so far. 35x12.50 Toyo Mts- 36 PSI all the way around. No lift. 4:10s. Speedo recalibrated and is maybe indicating .5 mph faster then actual speed when compared to my gps speed app (which was dead nuts on with stock wheels and tires), and this does affect computer mpgs a bit. The roads here in Eastern NC are mostly flat with some gentle rises on the highway which will shift my Gladiator back into 7th hear at highway speed. Maybe 50/50 7th and 8th gear at 75 mph.

My workday drive includes highway speeds at about 75-78 mph, 50mph, and a little 40 mph. I try not to accelerate too quickly. Last 2 tanks have been hand calculated at 13 to 13.3 mpg. Computer was showing about .3 or .4 more mpg.

Of course the higher highway speeds suck gas like beer at a frat party!!! :CWL::CWL: I'm trying to stay at 75 mph at the most, but any slower and you will be killed around here!!

PS. I've seen Gladiator mpg youtube videos where people get much better mpgs, but they're going at like 55 -60 mph mostly, and that's simply unrealistic for me.
 

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Just filled up the first tank, 17 mpg even. Mostly city, some highway going 65-70.

Will see how it changes with some miles though, and eventually with 410s or 456s.
 

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E85 has to be super cheap and plentiful in Iowa!

It runs silky smooth on E-85 and has great power.
My Silverado specs said if I ran it on E85 it would have something like 15 or 20 more HP.
I tried it out when towing my car hauler and yes, it actually was a difference I could feel. MPG honestly wasn't that much different. The dealer sales guy back then said he kept a spreadsheet of his trucks expected mpg on both E85 and other and plugged in the price differences to know at any given time or price spread which he was better off using economy-wise.
I loved the extra HP.
I'd like to be able to run it in my JT.
 

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This is really important. I "checked" speedo vs gps and was close but with the dash speed being mph rounded to the nearest unit, there was no way to tell if I was at 70.9 or 60.1. Looked like I was very close.

When I did mileage over a longer range, checked and averaged over a few 30 mile trips. I was off on my speedo by 1.25mph. Reset tire size and am close as I can get it, .02 off on a 30 mile trip.


I've also checked my truck's odometer and speedometer against my phone and a real GPS (Garmin) I found the speed aligned perfectly and when I drove 17+ miles after setting things to 0, when I stopped, they all agreed to the tenth of a mile. Not bad.
 

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3000 miles and still crappy lol. I am on heavy 35x10.5 super swampers and stock gearing.

Cheers
Jeep Gladiator Gasser real world fuel economy Screenshot_20211203-112022_Fuelio
What app are you running?
I like the detail.
For sh!ts and giggles, started tracking $ spent when i fill up to see what in spending on a monthly basis.

Also tracking using my odometer and comparing to what my truck calculates.
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