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I bought a used 2018 dodge charger SXT with 35,000 miles and I'm getting 14-15mpg and I specifically bought the v6 to save money on gas but now I'm upset thinking I should have bought a v8 if it's wasting the same amount of gas. Does anyone know what the problem could be?
 

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So, a question...
15 mpg as measured by the dash, or the gas pump? If the dash, maybe something wrong and should be fixable - 35k = still under warranty. What mileage do you get if fill the tank, drive a couple hundred miles and fill the tank - miles driven since last fill to top / gallons to refill to top?
if you are only getting 15 mpg, the car would likely not act right, and the cats would be blazing hot. Normal - at least for me - is 25 around town, and 30+ on the highway.
 

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I have a 15 SXT AWD that i drive as my daily and average 23-26 mpg depending on how i drive. Right now, I'm sitting at 26.4 mpg for my commute to work (70 miles round trip). I've never seen below 17mpg city but I could see how I could get below that if I didn't drive it so easy. The car weighs 4200lbs, the v6 is working hard in town to move that car. The v8 would be similar mileage intown. But when you get them on the open road, it's a little different story. The v6 does save you some gas money overall but only you can decide if it's enough. Other cars with v6's can do better mileage but aren't as big as the charger either.
 

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There is something wrong with your car, the V6 should get considerably better mileage. Change your air filter then disconnect the battery for 15 minutes to let the computer reset itself to the factory defaults. I get 22 mpg in town and 34-36 on the highway. Never gotten worse than 19 in town stuck in traffic jams.
 

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Use a GPS or a free speedometer smartphone app (or highway mile markers if need be) to make sure your speedometer/odometer isn't way off.

Then fill it right up to the top, zero one of the trip odometers, drive it till it's almost empty, and write down how many gallons it takes to refill it.

Do that three times and you'll know what your real world MPG is.
 

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There is something wrong with your car, the V6 should get considerably better mileage. Change your air filter then disconnect the battery for 15 minutes to let the computer reset itself to the factory defaults. I get 22 mpg in town and 34-36 on the highway. Never gotten worse than 19 in town stuck in traffic jams.
Mines never been that good. Best I've seen is 30mpg but mine is AWD.. so I'm sure that doesn't help.
 

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Around town there is not much difference between my wifes V6 (Pentastar) and my stroker. She gets around 19 and I average 17. Big difference is on the highway where she will get over 30mpg. If the air cleaner and such is clean, take the car on the highway for a cruise and see what you get. Calculate mpg at the pump and with the Evic. With the Evic I find it more accurate when I zero out total time in the trip section and zeroing out the mpg in the fuel economy section.
 

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As stated, check your air filter and make sure it's not clogged, also- Check Your Tires! If the tire pressures are too low, it will definitely lower your fuel mileage. IF the tires are the stock size, make sure they're filled per the specs on the door sticker. If they are not the stock size, you might have to play around a bit to find the best pressure. They should be 35-40 psi, depending.
What gas are you using? If you're using Joe Blow's Cheap Gas Special, try running fuel from a Top Tier station for a couple of tanks and see what you get.
 

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Discussion Starter · #11 ·
So, a question...
15 mpg as measured by the dash, or the gas pump? If the dash, maybe something wrong and should be fixable - 35k = still under warranty. What mileage do you get if fill the tank, drive a couple hundred miles and fill the tank - miles driven since last fill to top / gallons to refill to top?
if you are only getting 15 mpg, the car would likely not act right, and the cats would be blazing hot. Normal - at least for me - is 25 around town, and 30+ on the highway.
I get the same milage if I fill up the tank. I’m looking at the milage from the dashboard so hopefully it can be fixed. I’m at 36,000 so the warranty won’t cover. Wow you’re getting great milage on yours .
 

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My '12 3.6 SXT still gets mileage similar to that reported by Krautmaster. Around town about 20 and on the highway around 34 if I keep it below 70mph and about 30 running up the 5 at about 80-90. If the reset doesn't work, get it checked out.
 

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I'm a "spirited" V6 driver, mine gets about 18-20 in the city, 25-30 on the highway. 15 is too low. As said, check air filter, disconnect battery, maybe even try some Techron or other fuel injector cleaner.
 

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I get the same milage if I fill up the tank. I’m looking at the milage from the dashboard so hopefully it can be fixed. I’m at 36,000 so the warranty won’t cover. Wow you’re getting great milage on yours .
Can you please clarify this? Did you do as I and others instructed?
For example, you filled the tank to point that the dispenser shut off. Drove the car for a couple of hundred miles. Then filled the tank until the dispenser shut off. Then calculated how many miles you got on the amount that it took to fill the tank.
 

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How are all calculating pure city driving from hwy and combined driving? Are you all taking a day to just drive on city streets in stop and go driving conditions and calculating your mileage and fuel consumption.
 

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How are all calculating pure city driving from hwy and combined driving? Are you all taking a day to just drive on city streets in stop and go driving conditions and calculating your mileage and fuel consumption.
Pretty much "combined" is total miles / gallons put in tank. Most of what I do is "city", though not the same as someplace like a big city where it's more stop than go. City vs. Hwy can be estimated from what the dash says while driving. I have had instances where I've filled at Costco, and immediately gotten on I40 to Morrisville. Drove back and filled again at Costco same day. That's 298 miles at mostly 78 mph. Miles / gallons for that trip in is typically ~30 mpg. Open road, 78 mph, dashboard says around 32 mpg.
So far - fingers crossed - troopers don't look at you for 78 in the 70. I don't slow for radar or laser on I40 when i'm at that speed. Enough people going by like I'm standing still for them to get.

Then of course there's the people that pace me because they think I'm one of them even though I stick to the right lane. I'm a ham, and I've got a UHF stub antenna on the trunk, so that sorta contributes to that. Troopers here have various colored chargers for the slicktops - marked are silver / grey. They have two 850mhz stubs for voice and data - and sometimes other longer antennas. If they follow me too long and too close, I let off the gas long enough that they blow by.
 

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@Bobw, don't see a reply from the OP to your question to clarify his comment. I'm not sure if he followed your advice and calculated he is getting better mileage and has an error with his economy gauge. Or if he is getting low results that match his eco gauge.

The reason I asked how folks are determining their city mileage is because no 2 cities have the same conditions like you pointed out, and we all have different driving habits and some also have minor mods that impact fuel economy.

If someone had 215/65-17 on their sxt and switched over to 245/45-20 the actual speed will be about 2mph above the speedo at hwy speed. Put 245/40-20 on and the actual speed shifts the opposite direction. It amounts to a very small difference in MPG on the eco gauge, but it's just another variation affecting fuel economy as perceived using the eco gauge.

I just wonder how many owners actually calculate their city economy by actually driving on city surface streets for a day in stop and go burning half or 3/4 tank of gas while staying off the freeway and then filling up and doing the calculation. Very few. That's why when we make comparisons we see so much variation in our individual results in the city category. Hwy driving is not so complex because we can all find open streatches and let it go for a good drive at steady speeds. But even then there will be some locales where there is an upward streach were we get so-so mileage and then when we head back in the opposite downhill trajectory almost coasting at idle we see super mileage that favors overall economy.
 

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@Bobw, don't see a reply from the OP to your question to clarify his comment.......
Yeah. So as of right now....
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Your - and others - calcs are all valid. That's an awful low value for that car. If that much gas was really running through that engine, the cats would be white hot. O/P HAS to do the manual calcs. Gauge could be messed up.
 

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I am still running the 235/55-18 that was stock with my 12 and it's awesome chrome rims. I do use Conti Pure Contact All Season's and over a tank of gas and mixed driving, the dash meter is within 0.2 mpg of the "fill-up and divide" method. I have done it more than once and the variance is either way. Sometimes the dash says I did better, sometimes the fill method say I've done better. But that is no where near the mpg hit the OP is taking. you almost have to try to do that badly.
I wonder if there is a transmission or rear end problem making rpm's wrong or making the drivetrain work hard. I remember when the '12s came out there was a ton junk in the rear diff fluid.
Plugs lasted 100k and looked practically new when I changed mine out so this engine burns really clean in my experience. But that might be another thing to check.
Wrong grade oil in the engine? The 3.6 has a two-stage pump that runs very high pressure until oil temp hits about 160 degrees, then drops to about 41. Maybe stuck on high?
Just spit-balling ideas.
 
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