Gear ratio poll for 37” tires on 17” wheels 3.6 gasser

[JTGuy]

The difference between 4.88 and 5.13 is one less tooth on the 5.13 pinion gear. The 4.88 is stronger. Also the 5.13 really spins the driveshafts.

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[Sikjeep2]

Anyone who said 4:88 have you ever drove with 5:13? Man I love my truck with 5:13s.

Yes, Did 5:13 with 37s and regretted it everyday until I put 40s on.

Felt over geared, too much rpm running in 8th on the freeway. I wouldn't be against even 4:56 gears with 37s if a flat lander.

 

[Paulyester]

what gear? thats important

8th gear

 

[PuddleJumper]

8th gear

A little high for my taste and use but pretty spot on for most uses

 

[Lunentucker]

4.10 is stronger, but since you're not crawling it wouldn't likely matter.
4.88 is what I would do on it.

 

[Jeeperjamie]

I tow a 6048lb camper with mine on 37's stock gears. I get about 11 mpg going to Myrtle Beach. Around town about 17.2. I'm not regearing, that's perfectly fine for me. Mines a max tow though

 

[Wheelin98TJ]

The difference between 4.88 and 5.13 is one less tooth on the 5.13 pinion gear. The 4.88 is stronger. Also the 5.13 really spins the driveshafts.

4.88 is 39 on the ring and 8 on the pinion.

5.13 is 41 on the ring and also 8 on the pinion.

5.13 vs 4.88 on driveshaft speed is 5.12% faster.

I wouldn’t choose 4.88 over 5.13 based on strength. Not a big enough difference to matter.

 

[LostWoods]

If you've seen the pinion design you shouldn't worry about it's strength. That thing is thick all the way up to the teeth.

The 8AT has a super deep OD so 5.38 or gtfo. 5.13 on 37s is only slightly shorter than the stock Max Tow gearing which felt good but more gear is more better.

 

[Tommyd]

Yes, Did 5:13 with 37s and regretted it everyday until I put 40s on.

Felt over geared, too much rpm running in 8th on the freeway. I wouldn't be against even 4:56 gears with 37s if a flat lander.

Well I’m never on freeway and I pull stuff so I love it.

 

[intentsrig]

5.13’s all day. Had 5.13’s and 37’s on my JL for years.

Went with the same on the JT. Actually stays in 8th gear.

 

[bleda2002]

5.13s for sure. 4.88 and 37s is basically stock and 5.13s is just one step farther. The 1 step farther really helps with the extra weight, wind resistance and lift that usually come with 37s. On the highway the difference in rpm is less than 200, but I appreciate any extra torque off the line I can get, especially towing/hauling.

 

[Panthers65]

I love my 5.13s. I tow with my gladiator and wheel my gladiator, the 5.13's are so nice.

you aren't going to get great MPGs if your doing 90 on the interstate no matter what, you can throw that idea out the window. You are driving a vehicle with the aerodynamics of a brick, nothings going to change that. These engines are find sitting and reving a bit higher if that's your thing. Overgearing is the only way I've ever been happy in a Jeep, There's just no downside to selecting a deeper gear than you are thinking unless you run 90mpg 90% of the time.

Overgear, enjoy towing, offroading, and city driving.
Undergear and enjoy nothing.

 

[MPMB]

I love my 5.13s. I tow with my gladiator and wheel my gladiator, the 5.13's are so nice.

you aren't going to get great MPGs if your doing 90 on the interstate no matter what, you can throw that idea out the window.

This.

It's really easy to test what speed your JT maximizes speed and fuel, and what speed it uses more fuel to keep the speed up.

I was a little bummed I had to play tug-of-war with semis driving home on i44/40.

 

[dayusmc]

I do not rock crawl at all, I drive mostly on the streets and some sand roads.

My Mojave came with 4.10 and I put 37s and a Banks Pedal Monster on it, works great.

I probably won't regear it. If I do, I will put 4.88 in. The only extra weight I added was a Rubicon steel front bumper and skid plate, and the JL Audio stealth box and an amp (about another 70 pounds for the box, amp and 1/0 gauge wire).

If you are getting 37 KO2's I definitely wouldn't regear it if it has 4.10, I just don't think it is worth the money. If you are getting normal size 37s and you have 4.10 gears, I would try the Banks Pedal Monster first.

I think the 4.88 with 37s is just right. The question, is it worth the money.... If you have a lot of disposable income, I would do it. If you have to give up other modifications to do it, I would prioritize first. If you are adding a lot of weight to the truck that would make a difference also....

Just my $0.02....

 

[Badweather]

I really appreciate all the great responses and the poll results seems the consensus so far is 4.88 or 5.13.

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