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MPG and Range on the Ecodiesel

zouch

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i wonder how much variation there is based on people using the AC,… my Climate Control is almost always set to Auto.
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driventoadventure

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i wonder how much variation there is based on people using the AC,… my Climate Control is almost always set to Auto.
That, wind, and acceleration are probably going to be the biggest factors.

One thing I have been noticing, is that using manual shifting seems to improve my mileage - auto wants to down-shift way too much... Perhaps I will take the time and tanks to calculate the difference.
 

AC77

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Hello. My 22 ecodiesel gets 22 ish even with my 33x20 I tell you this pumping at Shell I get 400 on the tank. Any other like Chevron it says “ 373-393
Also I just installed the derringer tuner. Level 6 it’s still ok I get 21mpg. But I don’t have a heavy foot
 

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I do get a mileage hit when it's windy and it doesn't matter if it's a headwind or a crosswind because into a crosswind you have to tack into it....
 

zouch

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what is "too much"?
these 8-spd trannys are designed to break the work into 8 gear ranges, unlike trannys of old with fewer gears. i would expect them to (down)shift more to keep things in proper ranges, and don't think i'm going to be better at selecting that gear than the vehicle.


One thing I have been noticing, is that using manual shifting seems to improve my mileage - auto wants to down-shift way too much... Perhaps I will take the time and tanks to calculate the difference.
 

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Terpsmandan

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One thing I have been noticing, is that using manual shifting seems to improve my mileage - auto wants to down-shift way too much... Perhaps I will take the time and tanks to calculate the difference.
IMO the 8 speed on CC will downshift too quickly on inclines. I set the CC and lock it into M7 when I am in the hills near home, otherwise it will put a 8-7-6-5 or an 8-6-5 on me occasionally when 55 mph in 7th is about 1600 rpm and that is close to max torque. It should want to stay there but it doesn't....
 

driventoadventure

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what is "too much"?
these 8-spd trannys are designed to break the work into 8 gear ranges, unlike trannys of old with fewer gears. i would expect them to (down)shift more to keep things in proper ranges, and don't think i'm going to be better at selecting that gear than the vehicle.
Having that many gears is certainly better, since the goal is to keep your engine running at its most efficient speed at all times - hence why CVTs are so beneficial. Down shifting more does improve mileage when your power (specifically torque) bands are narrow, IE on all of the other engines for this vehicle except the hybrid, you have to be quicker to move to a gearing that allows the engine to run in that optimal band. When the max torque band is as long and flat as it is in the Ecodiesel, you don't need to down-shift to accelerate as frequently as it does since you can be getting maximum work out of your engine for a much longer period. This is one of the principles that many hybrids rely on to help their economy - having the torque of the electric motor allows it to provide acceleration and power while running the ICE at peak torque rather than peak horsepower to provide more economical work.
In my experience the transmission is too eager to downshift to provide more horsepower (which does provide faster acceleration) when there are plenty of times, such as just cruising through hills, where it could stay in the same gear and just run the engine slightly harder to maintain the same speed without sacrificing as much fuel economy. Anecdotally (and why I say I need to actually do some testing) while recently pulling a trailer and trying to maintain speeds, I could see observable differences of about 2.5mpg average more on a tank where I was using manual shifting and maintaining 8th gear much longer - using cruise control to manage throttle/speed keeping. Observing the economy indicator, would show that lugging the engine on a slight grade to maintain 75 would see approximately 11mpg while on a similar slight grade it would go down to 6 or 7 if it shifted to 7th to maintain a higher rpm. This doesn't represent more than anecdotal evidence since the conditions were not exactly repeated between observations, but it does serve as my basis to suggest more testing.
 

zouch

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i’m OK with letting it keep itself in it powerband and not working the turbo so hard at lower RPMs than it wants.
seems it should also do a better job of cooling itself at a given load if it’s turning over at a slightly higher RPM.

Having that many gears is certainly better, since the goal is to keep your engine running at its most efficient speed at all times - hence why CVTs are so beneficial. Down shifting more does improve mileage when your power (specifically torque) bands are narrow, IE on all of the other engines for this vehicle except the hybrid, you have to be quicker to move to a gearing that allows the engine to run in that optimal band. When the max torque band is as long and flat as it is in the Ecodiesel, you don't need to down-shift to accelerate as frequently as it does since you can be getting maximum work out of your engine for a much longer period. This is one of the principles that many hybrids rely on to help their economy - having the torque of the electric motor allows it to provide acceleration and power while running the ICE at peak torque rather than peak horsepower to provide more economical work.
In my experience the transmission is too eager to downshift to provide more horsepower (which does provide faster acceleration) when there are plenty of times, such as just cruising through hills, where it could stay in the same gear and just run the engine slightly harder to maintain the same speed without sacrificing as much fuel economy. Anecdotally (and why I say I need to actually do some testing) while recently pulling a trailer and trying to maintain speeds, I could see observable differences of about 2.5mpg average more on a tank where I was using manual shifting and maintaining 8th gear much longer - using cruise control to manage throttle/speed keeping. Observing the economy indicator, would show that lugging the engine on a slight grade to maintain 75 would see approximately 11mpg while on a similar slight grade it would go down to 6 or 7 if it shifted to 7th to maintain a higher rpm. This doesn't represent more than anecdotal evidence since the conditions were not exactly repeated between observations, but it does serve as my basis to suggest more testing.
 

NewbJLUOwner

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Hi All
I have a 2022 JLURD
Delivered 2/25
Today, my 1st real business trip all over Florida
I reset the computer just south of Daytona On I-95
I literally got to my hotel in Panama City FL,
Approximately 375 miles total
I "allegedly" averaged 77mph most of way......yuk yuk
I did refuel in Tallahassee, stopped at KFC, 1 rest stop for 5 mins
Computer says 25.5 avg as I arrived
Factory Tires & Wheels, 40 psi manufacturer specs I believe
I'm happy with that.
 

zouch

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if you RTFM (or just look at the sticker in the door sill that you climb over as you get in and out) i bet you'll find "manufacturer specs" are almost 10% lower than that.

pretty fair MPG though, otherwise, considering the fuel consumption on these things tanks exponentially as you get over about 65-70.

Hi All
I have a 2022 JLURD
Delivered 2/25
Today, my 1st real business trip all over Florida
I reset the computer just south of Daytona On I-95
I literally got to my hotel in Panama City FL,
Approximately 375 miles total
I "allegedly" averaged 77mph most of way......yuk yuk
I did refuel in Tallahassee, stopped at KFC, 1 rest stop for 5 mins
Computer says 25.5 avg as I arrived
Factory Tires & Wheels, 40 psi manufacturer specs I believe
I'm happy with that.
 

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driventoadventure

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...seems it should also do a better job of cooling itself at a given load if it’s turning over at a slightly higher RPM.
See, my past experience would totally agree with you, but I am finding that the ED seems to cool the oil better when it is lower and lugging. I found that allowing to rev higher, the eotect Delta would get to 35-40 deg f and the oil would get high enough to go into limp mode when towing in the Rockies... Forcing it to lug down to 1500-2000ish rpm and the deltas would come down to the high 20s and gauge mpg would increase. It wouldn't maintain speed as long obviously, but by not going into limp mode it certainly was faster overall​
Again, I need to do some testing, one thing for sure though - oil cooling is wholly inadequate on these...​
Forgive and misspellings etc, on mobile and autoassume is frustrating...​
 

zouch

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i hope you'll keep us posted on your results if you get around to some good testing!

(i hope you'll update us on what you meant by "the eotect Delta"; i know Eotect as an Optics company and am guessing that's not what you meant,...)


See, my past experience would totally agree with you, but I am finding that the ED seems to cool the oil better when it is lower and lugging. I found that allowing to rev higher, the eotect Delta would get to 35-40 deg f and the oil would get high enough to go into limp mode when towing in the Rockies... Forcing it to lug down to 1500-2000ish rpm and the deltas would come down to the high 20s and gauge mpg would increase. It wouldn't maintain speed as long obviously, but by not going into limp mode it certainly was faster overall​
Again, I need to do some testing, one thing for sure though - oil cooling is wholly inadequate on these...​
Forgive and misspellings etc, on mobile and autoassume is frustrating...​
 

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That, wind, and acceleration are probably going to be the biggest factors.

One thing I have been noticing, is that using manual shifting seems to improve my mileage - auto wants to down-shift way too much... Perhaps I will take the time and tanks to calculate the difference.
Elevation will have an impact too, but I'm not sure how significant it is with a diesel.
 

driventoadventure

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(i hope you'll update us on what you meant by "the eotect Delta"; i know Eotect as an Optics company and am guessing that's not what you meant,...)
Engine oil temperature Engine coolant temperature. It is a good Delta to observe for oil cooling performance. Sorry, borrowed the term from my power stroke experience since I thought it was fairly universal. Being on mobile doesn't help with formatting either.
 
 



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