What MPG are you getting?

And you are a fucking nitwit. I suppose my 16.8mpg with 3.73 gears was pulled out of someone's ass? Leave it to you to go off on a extreme tangent. Btw, nothing about you could ever injure me lol.

You are coming off as ignorant. Guess what - I have achieved more than 16.8 mpg at higher than 1800 rpm. I cruised at 65 mph, 3100 rpm with 31’s and 4.10s and got 18.5 mpg.

There are times when more rpm will hurt mpg but it is not a blanket statement like the way you put it. There are many times when more rpm helps efficiency. Too low of rpm lugs the motor and hurts efficiency.
 
You are coming off as ignorant. Guess what - I have achieved more than 16.8 mpg at higher than 1800 rpm. I cruised at 65 mph, 3100 rpm with 31’s and 4.10s and got 18.5 mpg.

There are times when more rpm will hurt mpg but it is not a blanket statement like the way you put it. There are many times when more rpm helps efficiency. Too low of rpm lugs the motor and hurts efficiency.

It is yourself that is coming off ignorant. Feel free to go back and read any of my prior statements and you will see I never proposed any extreme measures such as super high gearing as a panacea. Many others have confirmed in this thread the value of lowering cruise rpm's....refer to post # 147 as an example. I fail to understand all the Captain Obvious moments in this thread...we are not talking about "lugging" a engine at all.
 
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It is yourself that is coming off ignorant. Feel free to go back and read any of my prior statements and you will see I never proposed any extreme measures such as super high gearing as a panacea. Many others have confirmed in this thread the value of lowering cruise rpm's....refer to post # 147 as an example. I fail to understand all the Captain Obvious moments in this thread...we are not talking about "lugging" a engine at all.

Post 147's wonderful gas mileage is because he's going 55 mph, and not 70. It is not from lowering cruise rpm. With that logic, my 3100 rpm at 65 would have gotten poor mpg due to revving 3100. Quite the contrary, when I had stock 3.55 gears, 65 mph in 5th was 1800 rpm on 31's and I got much worse mpg, like 15.

Looking through your posts, I have a question....do you provide anything here besides baseless, contrary claims? I can not find anything useful from you, just stirring the pot garbage in practically every thread you participate in with no facts to prove any of it.
 
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Post 147's wonderful gas mileage is because he's going 55 mph, and not 70. It is not from lowering cruise rpm. With that logic, my 3100 rpm at 65 would have gotten poor mpg due to revving 3100. Quite the contrary, when I had stock 3.55 gears, 65 mph in 5th was 1800 rpm on 31's and I got much worse mpg, like 15.

When you lower your speed as he did the cruise rpm naturally comes down...what do you not understand about that logic?
 
When you lower your speed as he did the cruise rpm naturally comes down...what do you not understand about that logic?

Are you fucking blind? So what about my experience, where I go 65 at two different RPM, and the higher rpm netted better gas mileage? what do you not understand about that logic?
 
Looking through your posts, I have a question....do you provide anything here besides baseless, contrary claims? I can not find anything useful from you, just stirring the pot garbage in practically every thread you participate in with no facts to prove any of it.

That right there is the only true reason you are even here responding... ;)
 
Are you fucking blind? So what about my experience, where I go 65 at two different RPM, and the higher rpm netted better gas mileage? what do you not understand about that logic?

Are you fucking stupid? You are the one that just made an idiotic statement...read what you post before submitting it boob.

Well documented in this thread where I state if one has a reason for lowering their gear (larger, heavier wheels, excessive weight, ect.) then yes, you could see an improvement. Having your foot buried in the throttle to maintain a given speed because of handicaps will certainly affect your mpg.
 
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Mine is getting 15-16mpg depending on if I do more highway or back roads to work. 4.0L/AX-15/3.73 gears with 31s. Not sure how since I'm not nice to it, but I'll take it. My lifted XJ could barely break 13mpg.
 
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Upon extensive research and testing I've determined the best way to improve Jeep mileage...
Commute on my Harley!! 😂🤣 37 mpg all day.
20211226_165632.jpg
 
Expecting my new O2 sensors to arrive tm...hoping that will clear up the CEL. If I'm not mistaken I think I read somewhere that by turning off the OD switch the converter in these Jeeps will actually lock up in third gear...I was unaware of this. I will put that to the test next as most of my driving is at 45mph or less here.

Just to reiterate... this Jeep with 33" tires and 3.73 gears with the 42RLE is probably right on the edge of being less than ideal. My 1800rpm cruising rpm from the other day would likely be slightly improved if the engine were between 2000 - 2500rpm. In the wind and on inclines I could sense the need for a little more throttle position (no cruise control). At the current 16.8mpg would it be logical for me to re-gear? Absolutely not considering how long it would take just to break even with the near $2000 cost. If this were a serious offroad vehicle would I consider a re-gear? Absolutely...no doubt it would be much more responsive to those needs and I would not even be in this thread lol. I just hate for someone to stumble in here and expect an automatic increase in mpg just from new gearing. One needs to consider all the angles to make that decision.
 
Expecting my new O2 sensors to arrive tm...hoping that will clear up the CEL. If I'm not mistaken I think I read somewhere that by turning off the OD switch the converter in these Jeeps will actually lock up in third gear...I was unaware of this. I will put that to the test next as most of my driving is at 45mph or less here.

Just to reiterate... this Jeep with 33" tires and 3.73 gears with the 42RLE is probably right on the edge of being less than ideal. My 1800rpm cruising rpm from the other day would likely be slightly improved if the engine were between 2000 - 2500rpm. In the wind and on inclines I could sense the need for a little more throttle position (no cruise control). At the current 16.8mpg would it be logical for me to re-gear? Absolutely not considering how long it would take just to break even with the near $2000 cost. If this were a serious offroad vehicle would I consider a re-gear? Absolutely...no doubt it would be much more responsive to those needs and I would not even be in this thread lol. I just hate for someone to stumble in here and expect an automatic increase in mpg just from new gearing. One needs to consider all the angles to make that decision.

Maybe I’m misremembering but I don’t recall anyone saying to regear for mpg. But, I’m not going back through all the posts to verify. The reason to regear is power delivery. If you get an mpg increase, yay. A regear is indeed expensive and it doesn’t pay off unless you went from like 11 to 18 mpg.

All I ever tried to say is that the blanket statement of “more rpm wastes fuel” is not true. It is true sometimes, nowhere near all the time. I suppose I can’t speak for the intentions of others in this thread but that’s the only reason I chimed in.
 
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Some time ago, when i only had rear regeared and front still had 3.07, i was gonna do a fuel consumption test by driving with two different gear ratios.
Plan was to drive a full tank with 4.56 ratio, and then swap drive shafts and drive another tank with 3.07 ratio. Still regretting for not doing it, that was a perfect opportunity to put an end to this shit once and for all.
 
I think main difference would be transmission only and yes I would expect that too in a perfect world. You think weight might cause that much of a difference? I have a hardtop on but back seat is removed

I have taken my hard top off and I have no rear seat, I got slightly better milage with the hard top so I dont think its weight?
Heavy foot or O2,s would be my guess as its a bit too soon for your cats to be clogged up on an 06 and wouldn't clogged cats cause less power as well? (Presuming both not telling)

The way you drive a Manual through the gears both up and down make a difference to fuel consumption, I have mainly only driven stick shift in my 44 years of driving, and I think I have only had one Auto.

With 3.07,s and a 6 speed your not meant to rev the balls off them, you should change up and down when the engine tells you to and ignore the rev counter, gear should match road speed its quite simple until you start changing things.

On a side note, I still can't see the problem with 3.07 gearing in my TJ and I will get flamed for it as always but the 3.07 with 6 speed suits my driving style is all I can say! mind you I have had 3 speeding fines in 3 months $100 each all under 5.5mph above posted speed all just over 3mph above posted speed limit. We have unmanned speed cameras everywhere
 
Anyone looking to understand the relation of rpm, mileage, and throttle position needs to research volumetric efficiency. Here’s a tip- watch your MAP readings (if you have the ability) or even basic vacuum (if you don’t) while driving under the higher rpm vs lugging scenarios.
 
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