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JT owners post your MPG

ShadowsPapa

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Agree, unless you're gps verified speedo correct and hand calculate mileage then good luck getting accuracy. Maybe new thread to start with title appropriate. "Mileage Thread, gps corrected/hand calculated"? As just reading the dash isn't going to be accurate at all. From factory my sport s had tire height input of 32.24" for actual measured 31" tire height...then the calculator in the jeep itself will vary up to a mpg optimistic if you don't hand calculate miles to gallons actual.

The numbers i provided were gps corrected hand calculated if you need some more accurate to go by for a 6 speed, 3.73 on 35's. ;) City Winter Tank at 16.1 u.s. mpg, or 14.6 l/100km.
Oh, brother. So now you are saying that all of the speedometers are way off, and more........... to the point they are several mpg off?
I can see half, or one, perhaps. But then, I've checked our vehicles over the years, my Chevy, our GCs, and they've been almost right on the money.
I can verify the accuracy of mine - the GPS said my trip to Omaha was 162 miles, I counted down the miles as I went, and wow, the odo actually read 162 when I got there.
I fuel receipts are danged close to what the truck states I was getting when I average things out.

My Chevy was always spot-on. It told me how many gallons I had used, and I was able to get that many gallons in (but it was easy with that because the fill tube was straight to the tank) If it said "fuel used:21" you could get 21 back in it.

I've put my Garmin in each vehicle to verify as well - it's how I am - a bit untrusting sometimes because local police like to watch things like that. I'll stand by my MPG numbers.

Tire differences often come down to only 10-20 rotations per mile difference - won't make that variation in MPG numbers you are seeing here - do the math on that. A stock Overland tire and a Rubicon tire - the rotations per mile may be 1% difference, figure how many miles per tank, say 400 - is that going to make a difference from 20 to 15 mpg?
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ShadowsPapa

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FWIW I largely ignore the value on my cluster -- I calculate my mpg via an app on my phone, I just fill in the mileage and fuel amounts on fill-ups. On my trips I use a Garmin GPS and didn't see any discrepancies with my speedo. Seems like it does fine on the highway (~21 for me), and does poorly in stop+go and short distances between lights/stop signs (~13.5 for me). Over 114.389 gallons of gas and and 2015 miles I'm averaging 17.6mpg combined.
Mine also matched GPS - Garmin and built-in. When the GPS says a trip is 162 miles, it's 162 miles. When it says I'm doing 70, I'm doing 70.
These are NOT off - especially not enough to explain the differences from 14 mpg to 18 mpg and so on. Good grief, everyone's speedometer would have to be way off, by factors of several percent.
These vehicles are pretty good at tracking fuel use - I've used spreadsheets and other means over the years, they've gotten it pretty good.
Location, air temp, relative humidity, hills, wind, vehicle weight, tires, tire air pressure, speeds driven, the driven themselves, ESS and more.
My wife's Grand Cherokee - with HER driving she can blow 25 out of the water - me, in the same vehicle, same time of year, I have trouble keeping her Jeep over 23 and I try so she doesn't think I'm hammering on it. It's just how she drives compared to me - and yet I can do 19-21 on the JT most of the time. With the Falken tires, I've lost a few tenths now but that figures - more meat, more footprint, more rolling resistance.
 

danielspivey

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I have a stock max tow suspension wise, rubi wheels with 286/75r17 wildpeaks. Speedo was calibrated and I’m getting 17.5 mpg.

I have found if I really watch how I drive I can get closer to 20, but that’s just not realistic for me. This is my fun weekend/warm weather driver not my daily driver.
 

Jt-wrx

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i confirmed early on my 2014 ram 1500 was accurate to speed and within a few months of hand calculating mileage and comparing to the on-board computer it was usually within 1/2 a liter per km so i could largely trust everything...

i expected the same with the gladiator but since i changed quite a bit in terms of tire height i needed to re-program the tire height, then discovered it was well out so all the rpm data i was collecting to speeds to get an idea of where i started and to predict what i will need/want for the new tire heights and the mileage calcs...were useless

just providing my findings here, so they help others, if your speedo matches gps speeds at hwy velocity the computer will be close enough on mileage calcs to give people here the idea of what to expect

for the gearing side of things i need accurate speed so that rpm at my pre-determined speed goals can be realized, this data i now have, our typical max highway speed limit here is 110 km/h and pretty common to do 10-12 km/h over. I like the power level of 2200 rpm for holding most typical hills on the highway and have it as my max ceiling for for 6th gear at 120 km/h...in that case if i re-gear to that max ceiling i can go no further than 4.10's (currently have 3.73 and turn about 2000 rpm at that velocity) it's good, but requires more downshifts to 5th on some of the moderate hills, 2200 rpm has what seems to be a blend of power to mileage that i won't have as many downshifts while on cruise control on longer highway runs, peace out homies
 

robertm55

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I average 18 mpg with normal mixed area driving.
When I pull the travel trailer at 65 mph I get about 9 mpg.
When I do a full tank at 55 mph I get 11-12 mpg.(pulling the trailer)
I usually drive 75 on the highway if Im not towing, always use the adaptive cruise control,(I love it)
I have a stock rubicon on the falken tires and have 19,500 miles on the truck.
 

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ColoradoGlad

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Agree, unless you're gps verified speedo correct and hand calculate mileage then good luck getting accuracy. Maybe new thread to start with title appropriate. "Mileage Thread, gps corrected/hand calculated"? As just reading the dash isn't going to be accurate at all. From factory my sport s had tire height input of 32.24" for actual measured 31" tire height...then the calculator in the jeep itself will vary up to a mpg optimistic if you don't hand calculate miles to gallons actual.

The numbers i provided were gps corrected hand calculated if you need some more accurate to go by for a 6 speed, 3.73 on 35's. ;) City Winter Tank at 16.1 u.s. mpg, or 14.6 l/100km.
Good call out...
I calibrated my Speedometer exactly to my GPS...
Not just the speed, but the distance.
It took a few tweaks, but it's darn near perfect...

It will be interesting to see what becomes of the Plug-in Hybrid Wrangler/Gladiator..
I like the concept, but I think the price will be out of sight.. Even with the Government rebates..
My daughter drives a Pacifica Plug in Hybrid... I've never heard the gas engine run in it.. smile
The car actually has to run the gas engine at times to keep the gas fresh and systems lubed...
 

Gladiator4Runner

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has anyone looked into a chip/computer upgrade to get either more performance or efficiency?
 

Bbannongmu

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jlaf618

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My gladiator is showing 11.3 mpg. 600+ miles. I have a sport with the 2 inch mopar lift. 35s. I’m thinking the dealer didn’t calibrate after the modifications? Thoughts anyone?
 

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robertm55

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Depending how heavy you are on the gas, that mileage doesn't seem out of line for what you are running.
 

MarineHawk

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My gladiator is showing 11.3 mpg. 600+ miles. I have a sport with the 2 inch mopar lift. 35s. I’m thinking the dealer didn’t calibrate after the modifications? Thoughts anyone?
You can check easily by running a navigation system/GPS (and see if your speed is the same as your speedometer) or just see if your odometer matches the distance between mile markers.
 

shokker70

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My gladiator is showing 11.3 mpg. 600+ miles. I have a sport with the 2 inch mopar lift. 35s. I’m thinking the dealer didn’t calibrate after the modifications? Thoughts anyone?
That mileage is terrible IMO, but you def want to check it against something. I used an app based of GPS/satellites. Mine just felt off and still is. Anyone else use a Hypertech unit to calibrate? That's what the shop used and I redid it myself. Off by 2 MPH low speed and 77 is 70. My guess is they used JL settings, but just a guess. Heaven forbid someone actually do an update and get JT settings.
 

ShadowsPapa

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You can check easily by running a navigation system/GPS (and see if your speed is the same as your speedometer) or just see if your odometer matches the distance between mile markers.
Agreed - this is SOOOO easy to check with phone NAV system, the built-in NAV, mile markers, etc. - even a STOP WATCH.
No reason to "wonder" - check it.
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