10mpg w/37's

[Trippin01]

I keep seeing mileage all over the place from individuals on this forum. There are several that don't understand why I don't care for my JT as a daily Driver, well, 1st of all, I love my JT, but with 5.13 gears, 5x 76lb tires, I am truly getting just 10 mpg's on the highway. Now to be fair, when I throw my 33's with the stock wheels on, I get 20mpg. When I had the stock baloney skin Desert Dueler's, I got 22 mpg, great right? When I have the 37's on, and I go about 45-ish, I'm up to 18. and I'm not complaining about my JT's mileage because I know how to get better mileage, but once again, I have a car for that. My truck has never done better off road since I put the 37's on and changed the gearing. I wouldn't change a thing. My main point is, It's all a trade off, and different parts of the country require different setups. I live in the Rockies, go to MOAB and Ouray every year since I've had it, 2 now, going on 3. I hate the mileage going to the play areas, but I love the truck when I'm at the play areas. Big Bear was the deciding factor for going to the 5.13 gears. Rock gardens were painful with 37's and stock 4.10 gearing. Now that its assembled, it is a blast. I don't mind it being amazing for trails, and horrible as a DD, it's the nature of the beast with a 40 mile round trip to work. Gas cost alot, and the tires were $450 ea. last time I checked, so while I am a true believer the JT is not the ideal DD, it is a hell of a truck if you build it the way you need, and I'm sure I'm on the off-road end of the spectrum. So what ever you use your JT for, make it the best and share with everyone here what you use it for, so we can all learn. I love seeing JT's everywhere, but my favorite place to see them is in the wild, on the trails, in the Jeep Meca country and I love seeing the smiles and the side panels plastered with BOH's. So until gas is completely out of hand, I will save the bulk of my miles for trails, and the not the pavement jungles of the city. I'm going to hit 4-5 more trails this year, and I really hope to see you and your JT on those trails, because thats where the smiles are the biggest and the JT was meant to shine. Yes, Mr. Tazer has adjusted the math for Tire size and regearing. Smiles per gallon......................

Sponsored

 

[Gvsukids]

I keep seeing mileage all over the place, and individuals on this forum why I don't care for my JT as a daily Driver, well, 1st of all, I love my JT, but with 5.13 gears, 5x 76lb tires, I am truly getting just 10 mpg's on the highway,

Your choice. Either drive with lighter tires, or save more money for fuel. A salesman friend of mine has Kenda 35's and uses his as a DD.

 

[Smess]

I am guessing this is a gasser, my launch gasser with 4.10's and 35's was perfect. I probably could have gotten away with 37's if they were light.

5.13'S????? thats the reason

and if the speedo is not re-calibrated that avg number on the dash is wrong also.

I will say it one more time, if you want larger than 35's or care about fuel economy I would highly recommends the diesel

 

[HouseOfWolves]

Did you recalibrate your system with the new tire size?

Peeps neglect the impact of rotational mass and how it effects MPG. You have to include the weight of the tires, and the wheels vs. stock setup.

I love the look of 37s -- I don't need them. So, at some point I will bolt on 35s on the stock wheels I have.

 

[Rummie]

I keep seeing mileage all over the place, and individuals on this forum why I don't care for my JT as a daily Driver, well, 1st of all, I love my JT, but with 5.13 gears, 5x 76lb tires, I am truly getting just 10 mpg's on the highway,

Something is not right. I get better than that on the highway with very heavy 37s, 5.13s, and pulling a 3500 lb camper.

 

[Fcmalie]

Did you recalibrate your system with the new tire size?

Peeps neglect the impact of rotational mass and how it effects MPG. You have to include the weight of the tires, and the wheels vs. stock setup.

I love the look of 37s -- I don't need them. So, at some point I will bolt on 35s on the stock wheels I have.

I always considered 35s to be the biggest I would go, now I'm rethinking that because my tow vehicle is pushing the limits. I will probably stick to stock 33'sfor a while now.

 

[HouseOfWolves]

I am guessing this is a gasser, my launch gasser with 4.10's and 35's was perfect. I probably could have gotten away with 37's if they were light.

5.13'S????? thats the reason

and if the speedo is not re-calibrated that avg number on the dash is wrong also.

I will say it one more time, if you want larger than 35's or care about fuel economy I would highly recommends the diesel

Not trolling with this -- I haven't done the math -- does the MPG improvement on the diesel offset the costs in the fuel?

 

[NachoRuby]

Is your speedometer recalibrated for 37s? Seems extremely low, but then I'm stock other than 35s

 

[HouseOfWolves]

I always considered 35s to be the biggest I would go, now I'm rethinking that because my tow vehicle is pushing the limits. I will probably stick to stock 33'sfor a while now.

I have a 2020 JTR -- the black one in this pic. It is side-by-side with same model year JTR on 35s on stock wheels. 35s on stock wheels is the way as far as I am concerned.

 

[Average Oregonian]

Not trolling with this -- I haven't done the math -- does the MPG improvement on the diesel offset the costs in the fuel?

It depends on what numbers you use to calculate it, what economy you'd actually get in the real world on each version, and what the cost of gas vs diesel is in your area. When I played with the numbers, the payback period could be as soon as 36k miles or way out past 100k. Using the current prices from my closest station for regular versus diesel, and assuming an average of 15mpg on gas or 25mpg on diesel, it would be around 42k miles. If I use the values from the window stickers of 19mpg vs 24mpg, that takes it to something around 110k. But that does not account for the extra maintenance costs (DEF, oil changes, fuel filters, etc.).

Note: I am neither pro nor anti diesel, heh. And it's definitely a great option for those looking to run tall and/or heavy tires.

 

[HouseOfWolves]

It depends on what numbers you use to calculate it, what economy you'd actually get in the real world on each version, and what the cost of gas vs diesel is in your area. When I played with the numbers, the payback period could be as soon as 36k miles or way out past 100k. Using the current prices from my closest station for regular versus diesel, and assuming an average of 15mpg on gas or 25mpg on diesel, it would be around 42k miles. If I use the values from the window stickers of 19mpg vs 24mpg, that takes it to something around 110k. But that does not account for the extra maintenance costs (DEF, oil changes, fuel filters, etc.).

Note: I am neither pro nor anti diesel, heh. And it's definitely a great option for those looking to run tall and/or heavy tires.

I am in the camp of -- whatever whatever. I almost bought a JTRD. I liked the idea of additional Torque. Though, I wasn't committed to needing it.

Thanks for the info and back of the napkin calculations.

I use to live in Ontario -- have spent a ton of time all over Oregon. God's Country.

 

[RustySeatbelt]

Is that consistent? I recently did a trip up to the Little Rock area from San Antonio, wind was awful going up and I averaged about 11mpg. Coming home there really wasn't any wind and I was averaging 16. I'm on 37's with 5.13's also. I've definitely noticed that wind plays a massive factor on my mpg. I always set the adaptive cruise to 75mph, so wind (and sometimes hills) is really the only factor that changes. How fast are you normally cruising at?

 

[Toyfrog]

3k RPMs at 60 and in 7th gear?

 

[Stratus109]

Lol OP def does not have his ecu recalibrated for tires or gearing.

 

[HouseOfWolves]

Lol OP def does not have his ecu recalibrated for tires or gearing.

No need to be a dick.

I think we are collectively trying to figure out the root cause of the issue at hand.

Sponsored