Regearing with Overland Setup

[pearlxman]

Looking for confirmation I'm going in the right direction.

Current Setup:
2020 Rubicon automatic 3.6L
Alu Cab Canopy Camper
Steel bumper/winch
Fully loaded with batteries, water, etc.
3" AEV Dualsport lift kit
35" tires 20" wheels (came with JT used)

Currently I have pretty much lost 8th gear on the highway 65mph-75mph cruising speed and pretty much always 7th.

I want to change my tire setup to 37" tires on 17" wheels. From everything I've read, 5:13 gearing is what is recommended to get back 8th gear on the hwy and more power overall back to stock.

Is this the consensus or 4:88 or even higher than 5:13? Current setup pic *before bumper/winch add*

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[JT1]

Looking for confirmation I'm going in the right direction.

Current Setup:
2020 Rubicon automatic 3.6L
Alu Cab Canopy Camper
Steel bumper/winch
Fully loaded with batteries, water, etc.
3" AEV Dualsport lift kit
35" tires 20" wheels (came with JT used)

Currently I have pretty much lost 8th gear on the highway 65mph-75mph cruising speed and pretty much always 7th.

I want to change my tire setup to 37" tires on 17" wheels. From everything I've read, 5:13 gearing is what is recommended to get back 8th gear on the hwy and more power overall back to stock.

Is this the consensus or 4:88 or even higher than 5:13? Current setup pic *before bumper/winch add*

You are going to get a ton of opinions now.
5.13s in 8th are the same as 4.10s in 7th. So if you only need another 100 or 200 rpm to hold it in 8th, and you don't drive 85mph everywhere, look at 4.88s or 4.56s.

This calculator is handy: http://www.grimmjeeper.com/gears.html

 

[whysoserious]

As @JT1 said, the opinions will flow. I personally have 5.13's (Dana) and 37's (Mickey Baja Boss AT) and am very happy. I went with this due to having the same gearing and tire size in my '17 JK and it worked well for me.

You have a few JT folks there in Sac-o-tomatoes, on this forum. Maybe find one that will let you drive the difference? Hopefully they will chime in here. If you were here in Texas, I'd let you take it for a spin.

 

[Zachanadandy]

4.56 is closest to stock gearing and 37s. You've also added lots of weight and wind resistance. However I do tend to drive everywhere at 80-85mph so I'd stick with 4.88s. The idea that you're gaining any power back is more of a myth. As stated above, 5.13s in 8th is the same as 4.10s in 7th and it pretty much works it's way down from there. The only place you really gain anything is 1st gear, and even with 4.10s and 37s I've never felt it was lacking from a stop. It will spin the tires if I hammer the throttle. If you want to gain power buy a supercharger.

 

[deekyn]

 

[professorkx]

Yup, you are going to get a ton of opinions on this topic. I have regeared a lot of jeeps in my shop, including my son‘s Gladiator to 5:38 gears, but this change was to address towing, nothing more. He was actually expecting better mpg by getting into 8th more often, but it wasn’t realized…although towing was improved.

I didn’t buy a Gladiator (or any of my jeeps) for the gas mileage, because it drives like my corvette or because it‘s a great tow rig, I bought it because IMHO Jeeps are simply the best off-road (for me rock crawling) rig available that I can drive long distances to/from the trails in relative comfort and not damage parts on the trail.

I never changed from the 4.10 gears in my JK with 37s and just accepted that I would be slowing down driving over mountain passes…and I only tow a trailer once in a while, so towing isn’t my primary use.

With the automatic, my Gladiator has more acceleration power with 37’s than I ever expected, and it has plenty of power for passing. At this point, I’m not planning to swap gears, I‘ll just drive a little slower in the mountain passes and be happy with my 16ish mpg.

The best suggestion so far has been to find someone who has swapped gears and take their rig for a drive, you might be surprised…

 

[Churro]

Looking for confirmation I'm going in the right direction.

Current Setup:
2020 Rubicon automatic 3.6L
Alu Cab Canopy Camper
Steel bumper/winch
Fully loaded with batteries, water, etc.
3" AEV Dualsport lift kit
35" tires 20" wheels (came with JT used)

Currently I have pretty much lost 8th gear on the highway 65mph-75mph cruising speed and pretty much always 7th.

I want to change my tire setup to 37" tires on 17" wheels. From everything I've read, 5:13 gearing is what is recommended to get back 8th gear on the hwy and more power overall back to stock.

Is this the consensus or 4:88 or even higher than 5:13? Current setup pic *before bumper/winch add*

I went 4.88 with 37s. I was talked down from going with 5.13s because the pinion, I believe, gets pretty small and is weaker. Unless you have beefy built axles, be careful. I also shaved some weight with forged 17” wheels and C rated tires.

 

[RubiDukkie]

My setup is similar to yours. I am running Revolution 5.13 gears as was recommended by my 4x4 shop. Only a few weeks past the initial break-in. Been very pleased with how easily it sees 8th gear. The shift points feel good. Will be going back to Moab next month, so it will get a good workout driving there from Virginia.

My setup (hopefully gives you an idea of weight compared to yours):

2021 Rubicon automatic 3.6L
RSI Smarcap (heavy, but lighter than a full Alu-Cab setup)
OEM Steel front/rear bumper
Warn 12s winch
Accuair 4" Dynamic Lift
37" mud terrain tires 17" Method wheels including same for spare
44" metal toolbox in rear to hold recovery gear, tools, etc. (heavy)
ARB Hydraulic Recovery Jack (heavy)
5-gal. Jerry Can for fuel (currently empty)
5-gal. spare water can (currently empty)
In addition to OEM armor, skids for front & rear diffs, front & rear LCA (axle and frame side), rear lower shock mounts (all metal, not aluminum)
Rock Hard 4x4 Patriot Series Tube Sliders (replaced OEM sliders, heavier than OEM)
Adam's 1350 front driveshaft (not sure how weight compares to OEM)

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