What's your MPG with large tires and re-gearing?

33s, stock TJR 4.10s, 19mpg when I hyper mile. 14mpg towing.
My '87 YJ, 33s, 3.07s, carburetor, Peugeot 5speed, 25mpg all day on the Interstate.

Don't ya love technology?
 
2.5, 3.73:1 gears, automatic, 31's (but when i measured them they were actually 29.5's). Roughly 50/50 highway and town, never had it over 70.
The best so far (had it 4 months) is 14
However, just installed the CORRECT oxygen sensor (NTK part #23506) ... can already tell better running engine, over entire rpm range, hope to get better mileage now

Oxygen sensor? What was the deal with that


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For a long time I ran my 6-speed, 3.73 4.0 on 33’s at 2500+rpms. I stayed in 5th on the highways so I could keep my speed from dropping off. I zipped around town and kept it peppy. Driving this way I consistently got 11-13mpg average including city, highway and towing. About 6 weeks ago I started an experiment based on some of @billiebob ’s ideas. Now I’m running around 2000rpm as often as possible and my average is 14-15mpg.
 
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2.5, 3.73:1 gears, automatic, 31's (but when i measured them they were actually 29.5's). Roughly 50/50 highway and town, never had it over 70.
The best so far (had it 4 months) is 14
However, just installed the CORRECT oxygen sensor (NTK part #23506) ... can already tell better running engine, over entire rpm range, hope to get better mileage now
We criticize lots of government regs, but getting down to it, those parts which reduce pollution today also increase fuel economy.
 
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Now I’m running around 2000rpm as often as possible and my average is 14-15mpg.
Thats why OD evolved during the 1970s gas crisis. It ain't new technology. And thats why todays cars with 7, 8, 9 speed transmissions have 2, 3 Overdrive gears.

Sadly the mentality of running 3K rpm all day is why you can no longer buy a truck with a clutch. Its not that computers are smarter, it is that computers are not stupid.
 
Thats why OD evolved during the 1970s gas crisis. It ain't new technology. And thats why todays cars with 7, 8, 9 speed transmissions have 2, 3 Overdrive gears.

Sadly the mentality of running 3K rpm all day is why you can no longer buy a truck with a clutch. Its not that computers are smarter, it is that computers are not stupid.
I must say, you make the more liberal arguments look good. But the removal of the freedom to choose a clutch in a truck is what I’m opposed to. If you want to be stupid and run 3k rpms all day, you have every right too. When we were running out of whale oil we found other oils. It will be something else if we run out of them....
 
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the removal of the freedom to choose a clutch in a truck is what I’m opposed to
Then we best educate those who feel gearing for 3K rpm on the highway is intelligent. I've owned over 30 vehicles, only 4 of them had slush clutches.

Sort of like smoking in a restaurant..... no you don't have every right to add to our air pollution problems.
 
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Then we best educate the idiots who feel gearing for 3K rpm on the highway is intelligent. I've owned over 30 vehicles, only 4 of them had slush clutches.

Sort of like smoking in a restaurant..... no you don't have every right to add to our air pollution problems.
Why do we need to educate them? Many of them probably already know. Education isn’t the issue, personal freedom is.

It’s not like smoking in a restaurant. The restaurant is a private business. They set the rules. You own the car, you have every right to redline it if you want!;)
 
Why do we need to educate them? Many of them probably already know. Education isn’t the issue, personal freedom is.

It’s not like smoking in a restaurant. The restaurant is a private business. They set the rules. You own the car, you have every right to redline it if you want!;)
lol, I think Chris has some perspective on that regarding Sport Bikes. Not critical of your opinion JMT but I think you might be disappointed.
 
Oxygen sensor? What was the deal with that


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@Nicholas, my 97 2.5L had a NTK 02 sensor, but the wrong part number! I even saved it.
It is critical the correct 02 sensor is used or your jeep won't run right.
Once I installed the correct upstream 02 sensor NTK #23506 it now runs great.
It's such a critical part, I got a spare 02 sensor, just in case :)
 
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We criticize lots of government regs, but getting down to it, those parts which reduce pollution today also increase fuel economy.
Economics Goal: Miles Per Gallon Vs. Cost per Gallon.
Facts: The politicians from both side of the party makes money out of it.

Who benefits? Last time I checked not the TJ drivers !

Sorry for going tangent :(
 
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35s, 4.56 gears, ax-15 and 231 tcase with an empty jeep averaging 75 I got whopping 12.2 MPGs. The next tank I ran empty going 70 and went to 14.2MPG
 
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I'm in the 14-15mpg range with 33s/5 speed/4.88. I can do better if I'm paying attention.

That makes me an idiot who runs 3k at 75mph. The reality is that most of my sustained driving is closer to 2500rpm.
 
It’s not like smoking in a restaurant. The restaurant is a private business. They set the rules. You own the car, you have every right to redline it if you want!;)

In some states and areas the government is controlling smoking in restaurants.

I think the difference between your right to pollute with your car or not comes down to the fact that you're using a shared maintained road where rules apply. It's like how you can't legally purchase an old Willy's new anymore due to pollutants, yet you can buy the Mahindra UTV version.
 
Economics Goal: Miles Per Gallon Vs. Cost per Gallon.
Facts: The politicians from both side of the party makes money out of it.

Who benefits? Last time I checked not the TJ drivers !

Sorry for going tangent :(

Regardless of the cost of fuel, last time I checked you can only carry so much in your Jeep. I like to make the most of those precious 19 gallons.
 
I missed the RPM debacle happening in this thread. I run between 2500-3000 RPM. Thats where all my get-up-and-go is. If I get below that I barely move. MPG wise when I was on 33s, my best came from about 2700 RPM, it was not uncommon to hit 17/18 miles per gallon that way.
 
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