37's and MPG

tjeeper

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12-13. This is at 80-85 mph, and it usually is windy in Utah.

City about 14-15.





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DodgeZ

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Anyone change gears and get better performance and mileage?
 

Gorilla57

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37’s on TR beadlocks and 4.88’s......15 around town, 15 on the highway. Not great, but not bad. 75mph just kills mpg. If I stay 65mph, I’ll get 17-18mpg.
 

DodgeZ

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37’s on TR beadlocks and 4.88’s......15 around town, 15 on the highway. Not great, but not bad. 75mph just kills mpg. If I stay 65mph, I’ll get 17-18mpg.
were the gears worth it?
 

Gorilla57

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were the gears worth it?
I would say yes. Jeep doesn’t struggle at all and it uses all 8 gears. It accelerates just as fast on the on-ramps and passes cars easily on 2 lane roads. This thing is just a brick at highway speeds and the lift, tires, wheels, armor, etc all combine to kill the MPG.
 

Dkretden

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High 17's / low 18's around town driving. High 18's / low 19's highway 4.10 gears 3.6l
This is quite great. I am lucky to get 16mpg around town (urban) with my unmodified rubicon. Good stuff.
 

gbr

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37" Milestar Patagonia and 3.5" Metalcloak Gamechanger.

City: 17.7 if I drive really careful.
Hwy: 19 if I stay around 60-65 MPH

Stock 4.10s.
 

Gorilla57

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And just an FYI for those wondering about MPG. Don't necessarily believe the high numbers people claim to get. Are they hand calculating and did they add a Tazer or something similar to adjust tire size, gear ratio to get the odometer/speedo right? My numbers are low and it's due to all my extra weight and lift height. But, my tire size and gear ratio is adjusted via a Tazer, speedo is GPS verified and I hand calculate my MPG. I hit 8th gear by 50mph and just purrs along nicely at that speed. I knew I wouldn't get stock MPG numbers ever again, but I'm ok with that.
 

DodgeZ

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And just an FYI for those wondering about MPG. Don't necessarily believe the high numbers people claim to get. Are they hand calculating and did they add a Tazer or something similar to adjust tire size, gear ratio to get the odometer/speedo right? My numbers are low and it's due to all my extra weight and lift height. But, my tire size and gear ratio is adjusted via a Tazer, speedo is GPS verified and I hand calculate my MPG. I hit 8th gear by 50mph and just purrs along nicely at that speed. I knew I wouldn't get stock MPG numbers ever again, but I'm ok with that.
My question is... do you need gears? Do you get better mileage with 37s if you regear
 

Gorilla57

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My question is... do you need gears? Do you get better mileage with 37s if you regear
You need gears in order for the engine and trans to “try” and work like normal. You’ll never get the stock 4.10’s to push the 37’s as nice as 4.88’s will. Simple physics. I’d do it again.
 

Petey003

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What kind of mileage are you guys getting with 37's and the 3.6L?
18.5mpg 72-77mph
20.5mpg 62mph

37" General Grabber X3's (81lbs)
4.88 Gears in JLUR Auto
 

Varilux

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I keep a notebook in which I track (among other things) every tank of gas... yes, I know I have OCD.

With the stock 33" tires (before I deleted the spare), I was getting 17.7mpg (70% highway, 30% city).
With the stock 33" tires (after I deleted the spare), I was getting 18.8mpg (same split of driving).
With 37x12.5" Nitto RidgeGrapplers (used Mini-Tazer to reset tire size and still no spare), I get 16.7mpg.
 

No IFS

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When I did my 37’s noticed that my miles per gallon dropped a little but my smiles per gallon went up a lot, so it’s a push. Lol
 

efitzger

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High 15's mixed driving at elevation with stock gears and heavy 37x13.5 Cooper STT's. I can eke out 17-18 on road trips if I keep it around 65. Anything above 75 and it starts dropping really quickly.
 

Gorilla57

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A little update/addition to this thread. Helped nurse home a broke down truck from Flagstaff to Tucson yesterday. We peeled off when we hit south PHX, they were doing fine by that point. Averaged 62mph and got 19mpg. I was plenty happy. Got 15.0mpg going up to Flag going 70-75mph.
 

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