Go 4.56 gears or don't use OD?
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JK Enthusiast
Joined: Apr 2012
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From: St Louis
Go 4.56 gears or don't use OD?
2016 JKURHR, AUTO, 3.73
285/75 Toyo ATs, aftermarket rear bumper and carrier, winch coming soon.
Need this thing to be super cool with the highway, like actually cruise the speed limit. Trips consists of 3000 miles. Want the ECO light on as much as possible... Its based off engine load, so when its on, MPGs improve.
Live in midwest, don't wheel here, sees lots of pavement.
Will maybe... and Im talking maybe , might go to 37s in a couple years.. no guarantee. But will for sure always be a 285 or 315 tire Jeep.
Looking to do Mopar 4.56 gears, cause from the chart, they could work both with 35s or 37s.
Right now my tire measures 33.5" on the Jeep, so 4.56s is spot on, or would even add some pep
Or just don't use OD and not worry about regear? Cause it drives great on inclines not using OD.
Not looking to gain MPG, but don't want it to go in the crapper either.
4.10s seem like a waste of time and $$
285/75 Toyo ATs, aftermarket rear bumper and carrier, winch coming soon.
Need this thing to be super cool with the highway, like actually cruise the speed limit. Trips consists of 3000 miles. Want the ECO light on as much as possible... Its based off engine load, so when its on, MPGs improve.
Live in midwest, don't wheel here, sees lots of pavement.
Will maybe... and Im talking maybe , might go to 37s in a couple years.. no guarantee. But will for sure always be a 285 or 315 tire Jeep.
Looking to do Mopar 4.56 gears, cause from the chart, they could work both with 35s or 37s.
Right now my tire measures 33.5" on the Jeep, so 4.56s is spot on, or would even add some pep
Or just don't use OD and not worry about regear? Cause it drives great on inclines not using OD.
Not looking to gain MPG, but don't want it to go in the crapper either.
4.10s seem like a waste of time and $$
JK Newbie
Joined: Oct 2015
Posts: 23
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From: Denton Texas
IMO 4.56 gears with 35's would be minimum. I ran factory 4.10 with 315/70/17 on a 16' auto and while it was acceptable it was not ideal. I definitely would have preferred 4.56. This was on a light 2dr without a bunch of added weight. With a JKU you are around 500lb heavier than a JK plus you are more likely to have more passengers, cargo etc. The 4.88's seem like a better choice and would be a better match if you do ever decide to go larger in the future.
My fuel mileage averaged about 17mpg with 4.10's and "35's". Now with 5.38's on D60's and 40's, I lost about 3mpg. I now run just under 3000rpm @ 70mph and my eco light is on quite often.
My fuel mileage averaged about 17mpg with 4.10's and "35's". Now with 5.38's on D60's and 40's, I lost about 3mpg. I now run just under 3000rpm @ 70mph and my eco light is on quite often.
JK Enthusiast
Joined: May 2014
Posts: 356
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From: SoCal
IMO 4.56 gears with 35's would be minimum. I ran factory 4.10 with 315/70/17 on a 16' auto and while it was acceptable it was not ideal. I definitely would have preferred 4.56. This was on a light 2dr without a bunch of added weight. With a JKU you are around 500lb heavier than a JK plus you are more likely to have more passengers, cargo etc. The 4.88's seem like a better choice and would be a better match if you do ever decide to go larger in the future. My fuel mileage averaged about 17mpg with 4.10's and "35's". Now with 5.38's on D60's and 40's, I lost about 3mpg. I now run just under 3000rpm @ 70mph and my eco light is on quite often.
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JK Enthusiast
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From: St Louis
JK Super Freak
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From: Thunder Bay, Ontario
JK Jedi
Joined: Jun 2013
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From: Willow Park, TX
Do yourself a favor and re-gear. You will thank yourself every single time you get in and drive the jeep. "not using overdrive" is not a solution....lol. It's pretty windy out my way.....and every time I'm on the interstate doing 75 in a strong headwind, I recall how I would previously have had to downshift from 4th to 3rd at times just to keep going. Now I just cruise along in 5th as I should. I had been on 37s and 4.10 gears before that, so 5th was non-existent.
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JK Enthusiast
Joined: Apr 2012
Posts: 271
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From: St Louis
Do yourself a favor and re-gear. You will thank yourself every single time you get in and drive the jeep. "not using overdrive" is not a solution....lol. It's pretty windy out my way.....and every time I'm on the interstate doing 75 in a strong headwind, I recall how I would previously have had to downshift from 4th to 3rd at times just to keep going. Now I just cruise along in 5th as I should. I had been on 37s and 4.10 gears before that, so 5th was non-existent.
You running 4.56s?
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JK Jedi
Joined: Jun 2013
Posts: 11,363
Likes: 2,089
From: Willow Park, TX
I'd agree with your original post that 4.56 might be best for you as it they would work with 35s, and still be acceptable with 37s if you ever made that jump. Moving to 4.88s would be a bit aggressive unless you already had 37s, but just my opinion.
I drove over a year on 37s with 4.10s......by the end, I was so worn down. Wish I had regeared sooner than I did.
JK Freak
Joined: Oct 2014
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From: Huntington Beach, CA
Thread Starter
JK Enthusiast
Joined: Apr 2012
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From: St Louis
Especially if battling winds.
I'm not worried about off road performance vs highway, due to the fact we only wheel in Moab and that is just once a year. If we make it that way. And 4.56 seem that they are manageable if I decide on 37s in the far future... Like that .5% chance if I do