DEF Usage

40”JLURD

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Loving my Diesel Rubicon so far but I don’t believe we will get anywhere near the 10k miles per DEF tank that I heard previously. Mine was almost full when purchased and after about 3k miles I’m less than 1/4 of a tank. I prob have more miles on mine than most people but has anyone else noticed their usage of DEF? Not a big deal but just curious if my rate of DEF usage is typical.

5D16EA09-2FFD-4A22-8B0C-F7DC0EB89627.jpeg
I’m at about 1800 miles and only have 1/3 tank left. Started off full upon delivery





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rickinAZ

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No one appears to be getting anywhere near 10,000 miles/tank. Which doesn't alarm me in the least. But, FCA, why not just set expectations better aligned with reality? It's like the Demon's 9.6 second quarter mile time that they advertised the crap out of. I haven't seen a publication get within one second of that time. If the stars have to align to meet a metric, why put it out there as the result customers should expect?

What ever happened to under-promise, over-deliver?
 
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JLURD

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No one appears to be getting anywhere near 10,000 miles/tank. Which doesn't alarm me in the least. But, FCA, why not just set expectations better aligned with reality? It's like the Demon's 9.6 second quarter mile time that they advertised the crap out of. I haven't seen a publication get within one second of that time. If the stars have to align to meet a metric, why put it out there as the result customers should expect?

What ever happened to under-promise, over-deliver?
How many forum users are running bone stock weight and keeping the skinny pedal off the floor consistently enough to get the 25mpg average? Mine gets pretty damn close to their quoted diesel to DEF consumption ratio regardless. Not to mention, we still have a lot of folks figuring out that a “full” gauge does not equate to a full tank. I’d love to see a spreadsheet of only DEF use rates from people who hand filled to the neck, then adjusted for their actual fuel consumption.
 

AZ-Chris

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My rig is stock Rubicon plus a Warn Zeon 10s winch, RSE Rock Sliders and ARB twin compressor. I've currently got 6,100 miles on the clock and I consistently get 25 mpg in all around driving.

My DEF tank was topped off when I took delivery, and I've added 2 full, 2.5 gallon jugs of Blu-Def myself. My def tank guage is at 3/4 level right now. Def fluid isn't like liquid gold, so the cost is virtually inconsequential to me, but my consumption rate seems to be out of whack with what Jeep advertised. Though, considering it is still very early in the life cycle of my vehicle, perhaps the def consumption rate will revert to the rates stated by Jeep. Time will tell, I just want the engine to run trouble free for many years to come.
 

No Spark V6

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I've got 3200 miles on mine. Avg 27mpg, stock. 3/4 of a tank of def upon delivery. I wish I filled it but I didn't. I'm a little under 1/4 tank. The gauge is probably not accurate enough to extrapolate usage.
 

rickinAZ

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So...it looks like people are getting decent fuel economy, but their Diesels are guzzling DEF. How does that jive with the fuel and DEF usage march in lock step thought?
 

JNewton918

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I have a 2021 JLUR 3.0 I took delivery on Sept. 19th and I currently have round 4200 miles. I've already went through one tank of DEF. My average fuel economy is still in the low to mid 20s, roughly 22-24mpg. I do mostly highway driving as where my primary residence and my work location are 250 miles away one direction. When I do work I have a place to stay in town and will travel back home for reserve duty and days off of 3 or more.

I'm going to try what others have said on here about filling the DEF without going off the measurement in the instrument cluster and see if that changes anything. I did notice that my window sticker range for fuel economy is different then of MY2020s that I've seen. Maybe it's different programming or changes they made? Other than the DEF usage I've had no issues with the Jeep so far.
 

BoiLator

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Hi all, new to the Jeep club. Last night I purchased a 2021 JLUR w/ecodiesel. Today, although my DEF indicator was just shy of 3/4 full, I decided to top the DEF off. I was able to put 2.5 gals in and the indicator is still not showing full.

Does anyone believe the DEF indicator is accurate? Curious why it would show almost 3/4 full but I was able to add 2.5 gals. Indicator should have been registering just shy of 1/2 IMO.

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Hi all, new to the Jeep club. Last night I purchased a 2021 JLUR w/ecodiesel. Today, although my DEF indicator was just shy of 3/4 full, I decided to top the DEF off. I was able to put 2.5 gals in and the indicator is still not showing full.

Does anyone believe the DEF indicator is accurate? Curious why it would show almost 3/4 full but I was able to add 2.5 gals. Indicator should have been registering just shy of 1/2 IMO.

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The gauge is trash and it seems to be overestimating on most, if not all examples. Hence why anyone claiming terrible DEF range without hand-filling their tank to the neck is reporting inaccurate range.
 

BoiLator

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The gauge is trash and it seems to be overestimating on most, if not all examples. Hence why anyone claiming terrible DEF range without hand-filling their tank to the neck is reporting inaccurate range.
I’ve read that here on this forum, and maybe you were the one who stated hand filling to the neck; which is why I attempted to fill mine. Was a little taken back when the gauge didn’t change much even though I added a full box of DEF.
 

Yankee1019

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All DEF sold in NA should meet the ISO 22241 standard for AUS 32. Never overfill your DEF tank. This will likely cause an inaccurate gauge reading and can also trigger a fault code in the ECU. DEF usage will continuously vary based on the engine conditions (throttle, load, ... etc) so comparing DEF usage between vehicles probably isn't very useful.
 

Plongson

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All DEF sold in NA should meet the ISO 22241 standard for AUS 32. Never overfill your DEF tank. This will likely cause an inaccurate gauge reading and can also trigger a fault code in the ECU. DEF usage will continuously vary based on the engine conditions (throttle, load, ... etc) so comparing DEF usage between vehicles probably isn't very useful.

I'm not gonna call total bullshit on this post, but I've not only filled this DEF tank to the TOP more than once, I overfilled it to where it overfilled and made a miserable white frigg'n mess, and it never had any ill effects on the gauge or the performance of the engine....overfilling DEF will not hurt your Wrangler diesel, jez, don't scare people.

Now, I will say you are ABSOLUTELY correct that DEF usage is directly proportional to loading...the harder work a diesel the more DEF you are gonn'a use. Rabbit stop'n go, climbing grades with your foot planted and pulling heavy loads will all increase the DEF usage...period. To get 10k out of 5 gallons of DEF, you'd have to be putting around at 40 mph the entire 10k miles. So yes, comparing DEF usage between people is not useful.
 

Yankee1019

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I'm not gonna call total bullshit on this post
I can assure you that I know more about the SCR system than you. Just because you haven’t had an issue with overfilling the tank doesn’t mean anything other than you’ve never experienced an issue. With the way the level sensor works if there is no air gap between the DEF and the top of the tank it is possible for the system to interpret that as the tank being empty.
 

Plongson

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Ughhh, Respectfully, I'm not even going to get into discussion with you over this topic, or argue how you came upon such profound knowledge...there are more important points to consider like driving your Wrangler with a tin foil hat.
I will say you should consider changing your profile name to Chicken Little.

No offence, I just don't believe your postulation.
 
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Compression-Ignition

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All DEF sold in NA should meet the ISO 22241 standard for AUS 32. Never overfill your DEF tank. This will likely cause an inaccurate gauge reading and can also trigger a fault code in the ECU. DEF usage will continuously vary based on the engine conditions (throttle, load, ... etc) so comparing DEF usage between vehicles probably isn't very useful.
And how pray tell, would one go about getting a 'full tank'? Only fill when empty?

I like to fill when convenient to me. In the winter I'll trust the gauge and just make sure I'm going to keep it at least above a 1/4 tank. But once the temps warm up, I'm filling to the top of the neck. Mid Fall Season I'll fill to the neck again.
 

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