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Guys and Girls, I got my 4xe a couple months ago and have 2100 miles on it so far. I know there's a break in period for the engine to get to full efficiency, but I'm still clocking about 14.5 mpg, just on gas, which is way worse than the EPA estimate of 17-20. What are you guys getting? What am I missing? Should I bring this up with Jeep?
 

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What mode are you running in?

Can you share a little about an average day of driving? How far and what mode you drive in? Also include if you are charging every night? When you said you are getting 14.5, how are you pulling that number? Are you getting that from one of the trip odometers or from the screen that just shows MPG?
 

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Discussion Starter · #3 ·
Running in hybrid, no electricity. I don’t have consistent access to a plug atm. Value is from the odometer and a full tank.

What mode are you running in?

Can you share a little about an average day of driving? How far and what mode you drive in? Also include if you are charging every night? When you said you are getting 14.5, how are you pulling that number? Are you getting that from one of the trip odometers or from the screen that just shows MPG?
O
 

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I would think you should be up closer to 24MPG. Are you tracking actual gas mileage at fill-ups? If not, I would be curious to see what would happen if you reset all of the data. Reset the A trip odometer and the one on screen 5 in the middle of the dash.

Is your 4XE a Rubicon or Sahara? Stock wheels?
 

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I have a Rubicon 4exe, 37" tires with a 2" lift at the dealership (floor model). I'm getting 19.5 MPG even though more than 50% of my miles are in electric, other 50% are hybrid. Much lower than I expected with the amount of electric usage. Currently at 400 miles total.
 

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Is anyone getting good gas milage? 😐
I saw some posts showing 45MPG. I'm trying to figure out how!! Even fully charged, if I'm in hybrid mode, the 15 mile round trip to take my kids to school only puts me at 24MPG at the end of the trip.
 

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I saw some posts showing 45MPG. I'm trying to figure out how!! Even fully charged, if I'm in hybrid mode, the 15 mile round trip to take my kids to school only puts me at 24MPG at the end of the trip.
When we talk about gas mileage in PHEVs, we have to clarify how we are using them and how someone gets the number they are stating. As an example, today I have driven 24 miles on electric only. I also did most of my driving yesterday in electric only. So right now, my trip odometer is saying that I’m getting 53mpg. That’s not a real number because I haven’t used a drop of gas today.

The main MPG figure on screen 5 right now shows about 39MPG. But that’s not a real number because it’s figuring a lot of electric miles. I have had that one up to 47MPG but again, that’s with a lot of electric miles figured in.

So if someone posts that they are getting 45MPG, we have to inquire about their case use. In all reality, if you went for a couple of weeks without running the engine, you could get it to say 99MPG.

My biggest complaint about the 4XE is that it doesn’t display a MPkWh along side the MPG rating. I would like to see those to numbers broken out. Then, MPG would only tally off hybrid miles and MPkWh would tally off electric miles. That’s the only way to get true apples to apples comparisons. If my daily drive is 16 miles and yours is 64, we can’t compare numbers because I’ll have a way better ratio of electric to hybrid miles driven than you do. So my overall MPG will be in the 30s or 40s while yours will be in the 20s.
 

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I agree completely. Shouldn't 100% hybrid mode though on a full charge of the battery be getting better than 24MPG, on at 15 mile drive?

Jeep is advertising 50MPGe when fully charged in hybrid mode. What exact style of driving would it take to get those numbers? I've never gotten to 0% battery and yet I'm at 19.5MPG overall. That means in 400 miles of hybrid or electric-only, I'm averaging what Jeep advertises (20MPG) for running the 4xe on gas only. Obviously, there's some loss due to larger tires, but not that much!
 

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If it were me (my Rubicon 4xe is not built/delivered yet), I'd look at "fuel economy" with the following:

1kwh = .03 US-gal in terms of energy measure / 1US-gal = 33.4kwh

Since 15% of the 17.3kwh battery is in reserve, it takes ~15kwh to charge (ignoring battery charging inefficiency here). That is equal, energy-wise, to .45 gallons. If one goes 21 miles on 15kw, that yields almost 47mpg"e" which is pretty close to the EPA "e" rating. Looking at total miles driven and adding how many full charges you make (from "<1%") can tell you how much energy you use and using, the ratios, figure out your true "mpg". My guess is that the on board computer is going to be very close.

Example (I recall a video but can't find it now):
One full-tank and starting on a full charge, their Rubicon travelled 390+/- miles.
Assume that 15kwh was used to charge, so that's equal to .45 US-gal and then they filled up with almost 15+ gallons so I'll round-up to 16 gallons and add the .45 "gallon" from the battery; that yields 23.7mpg. I believe their 4xe trip computer stated 24mpg.

Hope this helps those trying to see how efficient/inefficient their Jeeps are running. I can't wait to do some controlled, scientific tests when I get mine.
 

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I agree completely. Shouldn't 100% hybrid mode though on a full charge of the battery be getting better than 24MPG, on at 15 mile drive?

Jeep is advertising 50MPGe when fully charged in hybrid mode. What exact style of driving would it take to get those numbers? I've never gotten to 0% battery and yet I'm at 19.5MPG overall. That means in 400 miles of hybrid or electric-only, I'm averaging what Jeep advertises (20MPG) for running the 4xe on gas only. Obviously, there's some loss due to larger tires, but not that much!
MPGE is not MPG. The 49MPGE rating is a formulaic efficiency rating of the vehicle when in electric mode. It is not a combined/hybrid gas mileage. As an example, the Tesla Model 3 is rated at 141 MPGE. It’s a confusing thing the EPA came up with to try to compare gas vehicles and alternative fuels vehicles like EVs and PHEVs. A lot of dealerships, automotive publishers and YouTube videos have miscommunicated what MPGE really is.
 

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Wrangler4XEFan has it right on MPG vs MPGe; just a comparison of efficiencies between electric/hybrid vehicles. Jeep only states what the EPA indicates based on the EPA's testing.

The scientific part of an mpg test/comparison requires the same route/temp/wind/duration/altitude/vehicle-loadout conditions. Flatlanders will get great electric-only range (and fuel range) while mountain residents may not. Bad driving habits in any environment make it worse. Lots of variables, obviously.
 

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I basically decided to not have any MPG numbers on the dash in my default configuration. But I am tracking my tank on one of the trip computers.
 

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The EPA's website 2021 Jeep Wrangler 4dr 4xe says that the 49MPGe includes Electric + Gas. That would mean when fully charged and a full tank of gas that (assuming perfect conditions, flat, no wind, etc) should get 49 MPGe. To me, that means hybrid mode but even if it was all electric, then all gas that's still no where near what we're seeing. Do you read this differently?

827
 

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Look closer at the formula. It says “electric + gas” but the formula says .0 gas. That’s the same way the formula is expressed on the website. It’s confusing the way they write it up but the formula for MPGE includes zero gas.
828
 

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The EPA's website 2021 Jeep Wrangler 4dr 4xe says that the 49MPGe includes Electric + Gas. That would mean when fully charged and a full tank of gas that (assuming perfect conditions, flat, no wind, etc) should get 49 MPGe. To me, that means hybrid mode but even if it was all electric, then all gas that's still no where near what we're seeing. Do you read this differently?

View attachment 827
Look at the 49 MPGe box....that shows zero (".0gal") of fuel used per 100miles in their "test". Since one (1) US-gallon of gas = 33.4kwh and the EPA says there are 68kwh needed for 100 miles, that means there are 2.04 equiv US-gal per 100 miles of electric (68kwh/33.4kwh = 2.04 equiv US-gal of gas). Take the 100miles divide by 2.04 equiv-gal = 49 MPGe.
 

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As for the MPG rating, they ran their test in the worst case scenario. They used eSave to bias the vehicle as much toward the gas engine as they could. To me, that’s pretty disingenuous. They should have just ran their test in hybrid mode after battery depletion. The auto industry and the EPA have arguments about how the EPA does their tests on PHEVs.
 
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