gears and mpg
- Thread starter LUISJG
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expedition4x4
Explorer
It really depends on the type of travel, terrain, and tire size
For Colorado where I reside I would want to have at max 33" tires on 4:10's due to hills. I am regearing my JK with 35's to 4:56's
For Colorado where I reside I would want to have at max 33" tires on 4:10's due to hills. I am regearing my JK with 35's to 4:56's
aristobrat
Observer
Do you have a JK? If so, which engine/transmission type (auto/manual)? There are some charts floating around that show the effect of tire/gear size.
JIMBO
Expedition Leader
:sombrero: With your 2014/4.10 gears, if you have a manual tranny, your stock 32" tires are about the best you can use for just mileage-
If you add any larger tires, your mileage will decrease, unless you regear-
With an auto, the 32" tires are right at the edge for mileage, if you wanted 33/35" tires you should regear-
If you're only worried about mileage, you don't want a jeep !
:costumed-smiley-007:wings: JIMBO
If you add any larger tires, your mileage will decrease, unless you regear-
With an auto, the 32" tires are right at the edge for mileage, if you wanted 33/35" tires you should regear-
If you're only worried about mileage, you don't want a jeep !
:costumed-smiley-007:wings: JIMBO
Depends on what you're running.
False. 2012+ 4.10 with 32s and the auto, is too low out of the box. RPMs at 60/100 is 2500, and one can barely eak out 20 MPG (that was a twisty road and I wasn't constantly doing 100). My best tank while stock on a decent highway (doing 60/100) was 18.6 MPG (had that 3 tanks in a row). Go to a light 33 and that'll drop your RPMs to ~2400. That will help - especially if you live in an area with no hills. We've heard constantly how the 2012+ with the auto and 4.10s is perfect for 35s. I'm running heavy 33s on mine, and if I don't have my trailer, it's great, and I won't hesitate to go to 35s. But the trailer and the mountain passes, I'm too high (and I have a ton of mountain passes to drive over when I drive south). But on the flats, I managed to get 18 MPG towing my trailer (with my heavy tires, and f/r bumpers).
JIMBO
Expedition Leader
:sombrero: This is notta black/white area, there are hundreds of opinions on this same subject and all the different terrain and driving habits and jeep mods, will determine the right/wrong
So the only WRONG advice is a single blanket statement-
:costumed-smiley-007:wings: JIMBO
So the only WRONG advice is a single blanket statement-
:costumed-smiley-007:wings: JIMBO
It's been pretty well stated and documented that the 2012+ with 4.10, auto and 32s, is geared too low. Which is why when you order one, it comes with 3.73 and 4.10 is an option.
Here's the gear chart at 60/100 with the 3.6L. Going up an inch or two (especially if it's a lighter tire) will have little impact on one's mileage - especially if they don't live in the mountains.
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JIMBO
Expedition Leader
:sombrero: The gear charts for the 3.8l/42rle auto have been documented for almost 7 years and there's still heated arguments over /4.10/4.88/5.13/5.38 diff gears--
It's gonna go on as long as the 2012 + jeeps are running around-
I know guys with the 2012 5spd autos, that are happy with 5.13 gears and they're daily Drivers-
It's a jungle out there so keep you mind open !
:costumed-smiley-007:wings: JIMBO
It's gonna go on as long as the 2012 + jeeps are running around-
I know guys with the 2012 5spd autos, that are happy with 5.13 gears and they're daily Drivers-
It's a jungle out there so keep you mind open !
:costumed-smiley-007:wings: JIMBO
expedition4x4
Explorer
My standard 2012 with 3.73's and 32" tires was great on MPG Now I am moving to 4.56 with my 35's
The auto has a lower ratio than the 6 spd.
Cole
Expedition Leader
Terrain and elevation can make a huge difference on that! If you live at 5k feet and drive to 13k feet weekly then you will use more gas with the higher ratio than the lower!
The OP lives in Texas. Unlikely he lives at 5k and is going to 13k weekly. And even the post you quoted stated "especially if they don't live in the mountains".
Edit, according to his location, and wiki, he's at ~440 ft.
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Cole
Expedition Leader
You still shouldn't make blanket statements about what is more efficient!
Load could also make a difference in the same way as my elevation example.