Do I need new gears on my 2013 Jeep Wrangler Unlimited Sahara if I install a 2.5" AEV lift and 34" tires? It currently has 3.73 gearing. It's a daily driver, though it sometimes sees the interstate when we go up to trails or over to Moab, camping, etc. I don't do any serious rock crawling; mostly muddy/snowy trails with my 4-year-old son who thinks it's the coolest thing in the world.

I'm asking because new gears are pretty expensive ($2k), and if I have to revise my budget that much, I'll have to go back to the boss for permission. And while she's beautiful, she's not always reasonable about Jeep expenditures...

 

You are fine with this setup unless you are unhappy with the performance "off the line". It will do better on the highway, you will just loose a little on the low end. I have 34" and 4:10 and it is fine. You will have slightly higher gears than me. As for a DD you will be fine and off road you may end up using low range a bit more often that's all.

 

I'm running the AEV 2.5 with true 33" Toyo OC M/T's on my 12 JKU auto with 3.73 gears in the hills of the Appalachian mountains. It's manageable and the AEV Procal was a noticeable improvement. I'd love to have 4:10's with my 33's but its not worth the cost. Once I step up to true 35's I'll opt for 4:56's at that time. Seems like you're right in between with 34's...

 

It just depends on what you like. I have the same setup. Hated the 3.73 even on stock tires. It could only be worse with bigger tires so I re-geared to 4.56 when the lockers went in.

My Jeep weighs 4900 lbs with no people in it. The gutless 3.8 running at 1600 rpm would not accelerate from 60 mph on the highway in 4th gear. Now it runs at 2000 and accelerates fine. With bigger tires it will run at 18-1900 rpm at 60 which will still be OK.

The factory gearing is all about federal MPG requirements. It wasn't geared for drive-ability or power.

 

You'll be fine with that setup.

 

I got 2014 Auto JKU 3.73, with 2.5" AEV AND 315/70/17 Duratrac. Love it on the road and off road!

 

 

He has a 2013 with 3.6 and should be fine with his setup.

Not a 3.8....

 

I'm running 35s with 3.73s on an auto and it's fine in the flatlands for sure. I did reset tire size in the computer and therefore shift points. However, when I vacationed in the mountains it wasn't so great. Long inclines keep it from upshifting. Even if I gave it more gas, it would downshift and then upshift again to the gear I was in but wouldn't hit overdrive, sometimes not even fourth. I guess what I'm saying is in the mountains the gas mileage will suffer.

 

No you don't... Not to be a smart ass but did you use the search function?