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EPA Rules Rebuke... ESS dead?

azjl#3

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GabeBoyTheGreat

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This, ess not the mandate, mpg is. They did not have to use ess to get mpg
The design of the ESS system is mandated if you want the credits. That is why early cars ESS did not have a disable button at all, because that was the requirment. The requirement was later relaxed to allow for a disable button, but only if the default setting was ESS on.

Now I imagine the requirement will change to vehicles installed with ESS will get the credit regardless of default status, or they will remove the incentive altogether. In either scenario, the DESIGN mandate will have been removed. This is the topic at hand, not whether or not ESS is required altogether.

Edit: here is an article that explains why ESS cannot be permanently disabled by auto makers https://tflcar.com/2019/02/auto-stop-start-ask-tfl/
 
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GabeBoyTheGreat

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I personally do not like ESS, and I use Tazer to make it go away. But, I appreciate that the starter, flywheel and electrical systems on our rigs are built to handle it. If it gets eliminated, we can expect lighter flywheels, and less robust starters - that's the natural order of things.
You do realize that one of the major ESS compromises with the manual transmission is that they used a lightweight flywheel to prevent starter wear, right? If anything, removal of ESS would result in a heavier, more robust flywheel.
 

Terrymo

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Ohhh... that kind of Man-date!
Not this kind of man-date ?
Like when my friends and I take our Jeeps out on adventures...

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Beat me to it…I’m not here to judge.
 

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azjl#3

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You do realize that one of the major ESS compromises with the manual transmission is that they used a lightweight flywheel to prevent starter wear, right? If anything, removal of ESS would result in a heavier, more robust flywheel.
is that why a 2024 JL manual can overheat a clutch and a 2014JK can't? Can you use a 2014 flywheel and clutch in a 24?
 

GabeBoyTheGreat

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is that why a 2024 JL manual can overheat a clutch and a 2014JK can't? Can you use a 2014 flywheel and clutch in a 24?
I am no expert, but based on what I have read on this forum, Jeep used a lightweight dual-mass flywheel to reduce starter wear and/or decrease restart times due to ESS. ACT has a fantastic video series that compares the JK clutch to the JL clutch.

But bottom line, yes, the bane of Jeep's existence was all due to ESS. The JK has a heavier, single mass flywheel that is more robust, and the additional mass/inertia makes it more difficult to stall.

Edit: also based on reading this forum, there are a couple of aftermarket companies that have tried to make a heavier flywheel for the JL, but they typically fail around 10k miles for some yet to be determined reason.
 

4x4 Mule

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Maybe, while they are working on the ESS fix, they can add an icon to turn off the horn that blows every time you close the door while the vehicle is running. Just maybe.
 

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2nd 392

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The design of the ESS system is mandated if you want the credits. That is why early cars ESS did not have a disable button at all, because that was the requirment. The requirement was later relaxed to allow for a disable button, but only if the default setting was ESS on.

Now I imagine the requirement will change to vehicles installed with ESS will get the credit regardless of default status, or they will remove the incentive altogether. In either scenario, the DESIGN mandate will have been removed. This is the topic at hand, not whether or not ESS is required altogether.

Edit: here is an article that explains why ESS cannot be permanently disabled by auto makers https://tflcar.com/2019/02/auto-stop-start-ask-tfl/
Just don’t anyone dare use the term “Mandate” we all know it wasn’t, simply
Jeep Wrangler JL EPA Rules Rebuke... ESS dead? 23F29D3A-9318-43DD-8BAE-1A7138442C3F
 
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KCSgtMaj

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An even better alternative would be to stop putting ethanol in fuel. The MPG loss plus the amount of fuel used /pollution created in making the ethanol is crazy. It also wastes a huge amount of ground water.
Yep, I’ve crunched the numbers myself many years ago with my wife’s car. Less energy per gallon of ethanol laced gasoline than regular unleaded.

When I was on recruiting duty in the 90’s we had flex fuel vehicles and once a month we were required to burn a tank of E85. The cars computer even knew what kind of fuel it was which I could not believe. The miles to empty was always about 10-15% less than regular unleaded. The crux of the whole thing was I had to drive 70 miles one way to fill up the tank once a month. FOOLISH!
 

Crazyhorse1962

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At least for stellantis the existence of a dual battery S/S system has caused untold millions in warranty claims. It is *very* clear that the paltry amount of engineering/tooling expense required to delete ESS from the production line will save a significant amount of money down the line.

All it takes is someone high up at corporate who actually gives a fuck to reach that realization.

Hell, I wouldn't be surprised if the entire expense is less than a single week of stop/start related warranty claims. Every set of batteries is $1000+ warranty cost, and we do lots. Not including rentals, tows, or other common required warranty expenses.
Agree 💯 nothing but wear and tear on the engine I wouldn't have purchased a Rubicon if I was worried about gas and emissions
 

azjl#3

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I am no expert, but based on what I have read on this forum, Jeep used a lightweight dual-mass flywheel to reduce starter wear and/or decrease restart times due to ESS. ACT has a fantastic video series that compares the JK clutch to the JL clutch.

But bottom line, yes, the bane of Jeep's existence was all due to ESS. The JK has a heavier, single mass flywheel that is more robust, and the additional mass/inertia makes it more difficult to stall.

Edit: also based on reading this forum, there are a couple of aftermarket companies that have tried to make a heavier flywheel for the JL, but they typically fail around 10k miles for some yet to be determined reason.
Thanks! So, one could, replace the flywheel in a post 2021 JL and use a good clutch pressure plate and not have overheating? I still cant get my head around a 4500lb vehicle overheating a clutch driving in town. Can the temperature sensor be deleted?
 

yokramer

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Thanks! So, one could, replace the flywheel in a post 2021 JL and use a good clutch pressure plate and not have overheating? I still cant get my head around a 4500lb vehicle overheating a clutch driving in town. Can the temperature sensor be deleted?
Its not quite that simple the manual trans has a ton of other issues than just the flywheel theres a whole saga around here in one of the sub forums of sad robots issues after replacing her factory clutch/flywheel and tons of others joined in with their issues.
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