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What is Average MPG

ShadowsPapa

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I find it interesting that when I start the Jeep after a fill, and go to the mpg menus and hit OK for reset, that when I get back to the average display, it has a positive reading - such as 16, for example. If my last tank showed 20 mpg average, filling the tank, starting the Jeep, resetting the numbers, it might display 17 mpg average even though I have not moved. So, it's obviously using some history as a basis to begin with. Once I get moving, say it's a speed limit 45 and easy going, it will jump right up to a much higher number. From then on, the average displayed will drop, or rise, depending on my driving. It always starts out with the last displayed average and goes from there. The display isn't for that specific trip, it's accumulative.

it may be calculating in the background for that "trip" but what gets displayed is the average since reset. Hand calculations demonstrate that.
 

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The exact answer I was looking for! Thanks a ton!

What is the source of this great document?

A
It's a third party service information but it gleams most of the info from MOPAR Tech Authority. I have to dig for the thread and will link if I find it.
 

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Help translate that to English for someone who is low on sleep.
Does "trip" mean between resets or between "key on events"?

I've found it (fuel eco menu) to be far less reactive than the trip menu, and thus far less reactive than I would expect between key on events, but less stable than I would expect if it were between resets. That experience has made me willing to believe the comment about maybe being the previous thousand miles or something like that.
 

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ShadowsPapa

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Help translate that to English for someone who is low on sleep.
Does "trip" mean between resets or between "key on events"?

I've found it (fuel eco menu) to be far less reactive than the trip menu, and thus far less reactive than I would expect between key on events, but less stable than I would expect if it were between resets. That experience has made me willing to believe the comment about maybe being the previous thousand miles or something like that.
Be careful how you read that. Trip is usually "key on to key off".
Start, leave garage, go around the block, park in garage, shut it off.

But what is displayed is NOT that trip. It's the average of the averages and frankly, I question that in places because, as Charles and I have found - sometimes their explanations are incorrect. We've found more than one case of that.

If the display was the number just for that trip, then it would not start out with your last displayed number and then build from there, like it does.
If the displayed number was for "that trip" then romping it and racing like hell would drop that number really fast - but it doesn't - if you have 300 miles since you last reset it, trying to get really bad mpg doesn't have a lot of impact.
But if you have only 70 miles since the reset, then whatever you do has a great impact on the displayed number.
Proof what you see is not for that trip, but the cumulative average since reset.

This is saying it's cumulative.......... the display isn't just for THAT "trip event" or start up to shut down event.
Jeep Gladiator What is Average MPG 1756664273960-yo


When I do a reset, I start with the screen I showed earlier, press OK to reset that,
Then I scroll down to the trip numbers, reset it for trip A, then scroll right and reset it for trip B.
If you don't do that, then it accumulates on that screen where the screen with the scale may show differently.
You can use the various screens to see your mpg average for an entire trip across the country and reset it when you get there, or for just that tank. It depends on which screens you look at or reset.
 

m998dna

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What is Average MPG?

The cumulative gallons of fuel burned while you're sitting and moving.

if you sit in your driveway with the engine running and watch the needle go to zero you will achieve zero miles per gallon. Once you start moving you will achieve more miles per gallon.

Divide the number of miles driven and gallons burned and there's your answer.

The average MPG on my 2025 Mojave X is 11.7 miles per gallon.

😉
 

ShadowsPapa

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What is Average MPG?

The cumulative gallons of fuel burned while you're sitting and moving.

if you sit in your driveway with the engine running and watch the needle go to zero you will achieve zero miles per gallon. Once you start moving you will achieve more miles per gallon.

Divide the number of miles driven and gallons burned and there's your answer.

The average MPG on my 2025 Mojave X is 11.7 miles per gallon.

😉
My X is doing 17. About 4300 miles on it
 

m998dna

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My X is doing 17. About 4300 miles on it
Yeah... mine has about 2,000. I'm perplexed with an 11.7 AVG. It moved up a bit this past weekend to 12.7. Got a little freeway driving in. I hope after 5,000 miles it gets better.
 

ShadowsPapa

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Yeah... mine has about 2,000. I'm perplexed with an 11.7 AVG. It moved up a bit this past weekend to 12.7. Got a little freeway driving in. I hope after 5,000 miles it gets better.
Mine started out in the 15s, then went to the 16s, and has been hanging around 17s lately.
Hope it gets at least a bit closer to what my others, the Overland versions, did.
 

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Chasm

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Yeah... mine has about 2,000. I'm perplexed with an 11.7 AVG. It moved up a bit this past weekend to 12.7. Got a little freeway driving in. I hope after 5,000 miles it gets better.
Mine did high 16s low 17s for the first 1500, then started ticking up to mid 18s now with 2500 miles.
 

Gladiatorx2

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My current Rubicon is the worst so far at a lifetime average of 16.8 mpg. I believe th as that the culprit is I am running fairly heavy 37's and wheels. I also have a heavy front bumper and winch...with a 3.5" lift.
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