12 jk with 35's power lose
 

I put 35's on my jk and have severe power lose what gears should I swap out to?

Not just gears you also need a programmer. I recommend Superchips flashpac for jk. As for gears 4.10 should do fine.

4.56.....

This is great, I've been waiting to see a thread regarding gearing :naw:

4.10 or 4.56. If you do a lot of highway driving and like to drive closer to 80 mph, you will likely be happier with 4.10. If that is not the case, and you also like to wheel your Jeep, then 4.56. If you look at the gear ratio charts, subtract 1" from the tire size to see where your RPMs will be at when driving 70 mph.

And if you are going to be in there swapping gears, put lockers in! You're already paying for the labor.

I put 315s on my 13 and I honestly don't think it's as bad of a dog as most have stated, only real time I notice it is getting on the highway. But I can cruise at 70 and I'm happy. Would the 4:10 increase mileage? I'm around 15-16 consistently, that would be a nice change if I could improve mpg.


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^^^This. I'm guessing you have 3.21s now. If you want to get back to near stock shift points you can use this formula to figure out what you need.

stock gear ratio/stock tire size x new tire size. Then round up to the next available gears.

For example on my rig I have 3.73s with stock tire size of 32 and went to 35s.

So, 3.73/32 = 0.1165625. 0.1165625 x 35 = 4.08. Since the next gear size is 4.10 that is what I would go with to go back to stock. Paying all that money to change one gear size wouldn't be worth it so I will go to 4.56s. My highway rpm will be a couple of hundred rpm higher than stock but nowhere near 3000 so I feel okay with it. And you will need to reprogram tire size in the computer to get back to the correct shift points.

Edit: I don't believe the charts take into consideration overdrive either.

All good info I knew about the programmer the gearing is what is throwing me off. I have a 6 speed, most gears are horrible but on Highway driving in sixth I actually start losing speed. Factory gearing is 3.21 and factory tire size was 225/75/16

If I'm doing math correctly I would need to find gears near 3.87 correct?

So those are 29s. (3.21/29)x35=3.87 so 4.10s should get you close to stock. Manuals tend to require, from what I've read, one numerical larger size than autos. If it was me, I would go 4.56s. Maybe someone with 35s, manual, running 4.56s (or 4.10s or 5.13s) will jump in with a little more insight.

4.10 would be best man.