Jeep 392 MPG / Gas Mileage thread

[BenLandry]

@900 miles now, so enjoying FULL RPM range and paddle shifting! I get about 12.4 MPG by the computer calcs, and only about 250 miles per tank on 91 oct here in AZ. If I drive like a granny it gets much better but that’s no fun. I have not been able to drive a full tank like granny yet, just can’t keep my foot out of it. I don’t really care about the fuel milage but I do wish it had a larger tank! So I read earlier in this thread that off road + locks out the 4cyl mode…I don’t like the sound of 4cyl mode either…but does the OR+ mode do anything else?

Try it…it’s fun, shift points change, gurgles and pops a lot more. It’s really sport mode on an SRT

 

[CornPop]

326 miles to date. Averaging 12.5

Geez, you too, huh?

 

[89138]

1,200 miles, averaging 11.9, mostly all city though.

 

[Rscx4]

One thing to remember...if you put 3 fat girls (~900 lbs) in your Wrangler 3.6 or 3.8 (Had both) you would lose mucho fuel mileage...at almost a 1000 lbs more and higher in stance the Jeep 392 does fairly well I got 15.7 average yesterday 300+ miles from Lake Charles to DFW...all I-10 and I-45...80-83 mph all the way in windy conditions...JK 3.8 I had with a Magnuson Supercharger would be much the same and required premium as well...all in all 392 is doing very well on fuel, yes a larger fuel tank would be great! even an additional 5 gallons...
Weight kills fuel mileage...392 is heav(ier) than the norm....And of course Jeeps are like holding up a 4X8 sheet of plywood and running against the wind as well...

3 fat girls… that may be the ticket to keeping out of 4-cyl mode.

 

[S&S392]

Went to Moab followed my buddy in his motorhome so around 65 to 70 mph, got 20.5 MPG there.
strong head wind coming home got 17.5. around town 13 to 13.5 on 37's

 

[dog]

Normal, relatively assertive, stop and go driving on the 405 in traffic every morning, I'm sitting between 10 and 11 depending how many times I romp the throttle for fun. But in general, regular short distance driving I'm payin' about 5 bucks per 10 miles just to drive it with fuel prices around here. Do I care? Not really. Do I still think about it when I'm at the pump? Yes, haha. End of the day, still 1000% in love with it approaching 10k miles in 9 months of ownership.

 

[byhumba]

One tear at the pump...100s of smiles the next 200+ miles.

 

[Hayabusa]

Member of the 12.5 Club here. Around town stuff in a suburban area, 93 octane Sunoco.

Have run American Muscle all my life. Now, as a retiree, have to keep it to 2 rides vs having a 3rd "toy car". The 392 is how I roll.

Sold my toy car, Widebody Hellcat Redeye, to get my wife a car...new Mini Cooper S convertible with John Cooper Works factory exhaust/upgrades. She loves it, I think it's a fun little car. Getting 29.5 mpg, around town driving. It has less than 300 miles on it...not even broken in!

Love my rig, wife loves her car...life is good. Cool having 2 niche vehicles without being required to have something more "practical" at this stage of life! Our choices balance the household MPG number

 

[cgrosen324]

2021 392 XR: Trip to Zion this past weekend: 17.3 mpg cruising between 75-80…zero off road this time around.

 

[Turboencabulator]

We took the family on a long 1,855 drive over the mountains and through the woods to grandma's house on the beach. I averaged 17.1 mpg. The average MPG on the page 5 screen slowly creeped up from the 12.7 mpg I normally get but it was never truly accurate.

What impressed me most was the range between pitstops on the freeway. I was getting a range of around 340 miles on a full tank, which is great! That's works out to about 4 hours between tech stops which is perfect, because it's about the same exact time I need to stretch my legs, hit the head, and grab something to drink. I was worried the range was going to be a problem because I normally get in the mid 200's, but 341 miles was a pleasant surprise.

I was also very impressed with how accurate the computers range prediction software was on the trip. I like to use GasBuddy to plan out my fuel stops and I try and leave maybe 40 miles in the tank as reserve. After driving 300 miles I was finding the Jeep's range estimate had 42 miles of range remaining which is within 1% of what it predicted. That gave me confidence in the Jeep's range accuracy, which matched my fuel consumption calculations at the pump. Not too shabby for a 470 hp brick. (pics or it didn't happen)

 

[Earl 392]

Has anyone put 100 octane or higher in yet? Obviously unleaded. I’m sitting on a 100 gallons of it and I’ve been really tempted to try. Performance yes but minimal, I really just love the smell.

Do it.

 

[Earl 392]

We took the family on a long 1,855 drive over the mountains and through the woods to grandma's house on the beach. I averaged 17.1 mpg. The average MPG on the page 5 screen slowly creeped up from the 12.7 mpg I normally get but it was never truly accurate.

What impressed me most was the range between pitstops on the freeway. I was getting a range of around 340 miles on a full tank, which is great! That's works out to about 4 hours between tech stops which is perfect, because it's about the same exact time I need to stretch my legs, hit the head, and grab something to drink. I was worried the range was going to be a problem because I normally get in the mid 200's, but 341 miles was a pleasant surprise.

I was also very impressed with how accurate the computers range prediction software was on the trip. I like to use GasBuddy to plan out my fuel stops and I try and leave maybe 40 miles in the tank as reserve. After driving 300 miles I was finding the Jeep's range estimate had 42 miles of range remaining which is within 1% of what it predicted. That gave me confidence in the Jeep's range accuracy, which matched my fuel consumption calculations at the pump. Not too shabby for a 470 hp brick. (pics or it didn't happen)

View attachment 36732
View attachment 36733

Your Jeep be very thirsty

 

[Mallcrawler_392]

 

[Uncommon Sense]

I got about 17.5 driving from Chicago to Detroit over the weekend. Could only muster about 15.5 on the way back as it was really windy. Usually at 70-75 mph using ACC probably 80% of the trip.

I only get around 9mpg though driving in Chicago stop N go traffic though.

 

[Earl 392]

I got about 17.5 driving from Chicago to Detroit over the weekend. Could only muster about 15.5 on the way back as it was really windy. Usually at 70-75 mph using ACC probably 80% of the trip.

I only get around 9mpg though driving in Chicago stop N go traffic though.

Yep 15.5-8 35’s with 3.73 17 was the best ever for about 150 miles

 

[SunsetHill]

2024 392, stock 35's. While traveling between cities, the MPG reading on my screen has been as high as 18.4 mpg but that reading must change constantly. I do the math at fill-up time for the readings I am more familiar with.

Aw, shucks, rather than typing I'll just post the spreadsheet I made for myself, if you don't mind the extraneous detail.

I seem to get 9 mpg just tooling around the city while getting 16 mph out on the open road.