Can Believe my gas mileage

WXman

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I've seen 27 on the highway. Mixed city/highway while stock 21-23 MPGs depending on A/C usage.

Now, with the 34x11.50s and lift I've been seeing 18 MPGs mixed.

The mileage is phenomenal on the JL. It was pretty good on JK too, but the JL seems to be consistently 2 MPG better in the real world.
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DravenGSX

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I have no clue how you Rubicon owners are getting this kind of MPGs. At 75 MPH on flat Florida highway in my Rubicon, it sits at 14.9 MPG. My current average is 13.4... completely stock, 400 miles on the ODO. Maybe it's the soft top? It rarely goes into 8th gear and rides at 2800-3200 RPM at 75.
 
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Richamby

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What does the MPG meter show when you are cursing at 65 mph? My Jeep will hold 8th gear and show over 22 to 23 mpg.

You are pushing a big flat not aerodynamic vehicle at 75.
 

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What does the MPG meter show when you are cursing at 65 mph? My Jeep will hold 8th gear and show over 22 to 23 mpg.

You are pushing a big flat not aerodynamic vehicle at 75.
Oh, it has aerodynamics...

The aerodynamics of a *brick*... :)
 

WXman

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I have no clue how you Rubicon owners are getting this kind of MPGs. At 75 MPH on flat Florida highway in my Rubicon, it sits at 14.9 MPG. My current average is 13.4... completely stock, 400 miles on the ODO. Maybe it's the soft top? It rarely goes into 8th gear and rides at 2800-3200 RPM at 75.
What I've noticed is that the Rubicon owners always report the lowest MPGs, even if tire sizes are compared apples to apples with other models.. So, to me that says the extra weight of the Rubicon combined with the 4.10 axle ratio is killing the efficiency. That's really the only explanation.
 

Kevman

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Can't seem to crack 17.3 mostly city in my Sahara. Only 800 miles though so hopefully it will improve.
 

DravenGSX

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What does the MPG meter show when you are cursing at 65 mph? My Jeep will hold 8th gear and show over 22 to 23 mpg.

You are pushing a big flat not aerodynamic vehicle at 75.
At 65 it rides pretty much the same, 14-15 MPG. I was surprised, to say the least. I get that it's not aerodynamic, but geez. I had that same motor and trans in a JGC, and it rocked mid-20s.

What I've noticed is that the Rubicon owners always report the lowest MPGs, even if tire sizes are compared apples to apples with other models.. So, to me that says the extra weight of the Rubicon combined with the 4.10 axle ratio is killing the efficiency. That's really the only explanation.
The 4.10 gear is definitely making an impact - like I said it cruises at 2800-3200 RPM. I'm surprised though that it struggles to go into 8th gear. I have 35s on my truck with 3.92 gear, and it lives in 8th gear on the highway. Apples to oranges, I know - but it's all that I can compare it to.
 

Bingy

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Im getting really good mileage on my 8 speed auto Sahara. I'm lifted with larger tires also. Maybe I have a gem...

20180911_133424.jpg
 
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Shots

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I'll start by saying, taking pictures while driving (especially 63 mph) is a bad idea. Okay now that the dad moment is out of the way.
After a short stretch of interstate (going to Summit Racing) it seems that right around the 65 range seems to be the sweet spot. I wasn't driving it for long, but according to the calculator that's where I saw the most efficiency. I'd say you're right where you should be at that speed with those mods. These things are amazingly efficient compared to what I'm used to.
 

spurly

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You guys should check out fuelly.com

Its completely free and an easy way to track your mileage over time, and you can compare your stats to similar vehicles. I've been using it for years with all my vehicles.

It's super easy to use too. If you set up your profile so you can text, you text the number with 3 things. Mileage, price per gallon, and distance. 357.2, 2.659, 20.646 (Anything after distance is added to the comments) within seconds I get a text back with my current rank mpg and the lifetime average. If you visit the website you see a lot more information. Lifetime dollars spent, total gallons, best/worse mpg, trends over time, etc. And then you can view other vehicles to see how you compare.

I'm doing this from my phone so hopefully the screen shots come through.

Screenshot_20180912-101853_Message+.jpg


Screenshot_20180912-101922_Chrome.jpg
 

Gadgetguru

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Wife seems to be getting 20-22mpg with her commute and shopping trips. Very little highway. Won't stay like that for long, wheels and tires arrive next week. :)

JLU Sahara 6 speed
 

Prozac

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I'm running a Sahara with Rubicon Take offs and getting about 20MPG.
 

Uhdinator

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Things that come to mind:
Many posts don't mention the complete list of variables needed when comparing MPG.
What motor transmission combo?
Average RPM range that resulted in MPG listed?
Size tires and PSI if not stock?
Was the speedo re calibrated?
Was the cal done using mfr listed size or actually measured?
4 dr or 2 dr? (its been mentioned in reviews the 4 dr feel a bit under powered with the 2.0L)
Fuel octane used.

My 2dr Sport 2.0L A8 was modded by the dealer with 2" spacers, wheels and 305/65/17 MT tires. The speedo was reading 70 while my iPhone was reading 62 mph. They said they re cal'd the speedo and included the RC cal tool with the jeep.

I connected the RC calibrator and when i selected speedo cal the last setting used came up as 34." Mfr size is listed as 32.7 and likely possible if the tires are inflated to 65 psi max cold rating. i have them at 30 psi and they measure 32." Point being when i corrected the speedo my MPG went from 26 to 24. Not doing the re cal when changing tire size, it is possible the ABS, traction control, and steering can be effected. I believe the amount of steering assist is variable based on speed. going slower increases assist amount.

Even my 2003 Rubi auto had adaptive learning with the auto trans. When I first got it, shifting was at lower rpm, over time it adapts to how aggressively you drive and the shift points gradually change.

The trick guys have mentioned on Challenger forums is that a lot of city stop and go driving would result in the car feeling doggy after a while. Once a month you disconnect the battery or pull the ECU fuse and reconnect after a few minutes and the Auto trans learn feature is reset. Then drive it in a bit more spirited manner and it seems as if the performance was renewed. This might help on auto jeeps that have bigger tires too. Do the reset then re cal speedo and see if it helps.

I run 91 to 93 and get ethanol free gas when i can find it. i know with modern cars and even my Harley if I run low octane it will still run with it, but the performance is reduced as it retards timing to prevent knock. The few bucks extra for premium may result in slightly better MPG and your jeep struggling a little less if that is the case due to bigger tires. You might get part of the added cost back in MPG so in effect you're paying .25 extra a gal for premium vs the actual .50 more.

The Rubicon's likely get poor MPG with the stock tires due to the 4:10 axles and running at over 2500 rpm at highway speeds. My 2.0L auto runs at 1700-1800 rpm @ 70 MPH in 8th gear. The power doesn't seem a problem likely due to the E torque assist. I will stay in the 33" tire range with 3:45 gearing and be happy. Going larger than 33" on a non-Rubicon and you can expect lesser performance or longevity of components. Oh course it all depends on how you use your jeep as well. I'm not judging anyone for what they choose to do. I just believe its wise to mention it for those new Jeeper's trying to learn. That's what makes forums a great resource.
 

WranglerMan

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I recently chalked my 315 KO2’s on my lifted Sahara and went down to 29 lbs cold and heated they are running 10% higher on avg, my mpg’s running back and forth to work in DT Houston which is mostly highway with some stop and go has been 20-21 with my Tazer calibrated speedo
 

offcamber

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I run 37x13.5 Cooper Discovery STT pro's on mopar beadlocks. I run them at 24psi and I get better gas mileage with them than I did with the 33" BFG's.
 
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