Sorry for the newb questions but I'm trying to learn here about regearing.


I'm running an automatic 2009 Jku with a 2 inch lift, 33's, with I believe the stock 3.12 gears. Im not sure. The jeep lacks power especially going up hills. Its very sluggish. I've been reading about the gears and it sounds like I need to regear in order to gain back the power lost from the mods.

My questions are:

Will changing the gears make a big difference in how it pulls?

Should I go with 4.88s? I will eventually switch to 35,s. so I would be running the 33s for awhile with it.

Will it improve my mpg? Currently averaging 13.5 mpg. What kind of improvements have you seen?

Will I need to upgrade any other parts to accommodate the new gears? Like the axles or anything?

And last question, for those of you who have regeared, what did you pay the shop? If you dont mind saying. And was it worth it?

I do go off roading also if it makes a difference and this is my daily driver. Apart from bike that is.

Thanks

 

Oh and here is my jeep

 

I believe the only gears available that year for non-Rubicon automatics was 3:73.

33s should make very little difference over stock. Gears are one of the best power mods you can make but might not be necessary right now. Try a Superchips and/or a Sprintbooster. If later, you do go 35s and gears, the Superchips and Sprintbooster will still be useful and compliment your gears.

4:88s or 5:13s would be best. 4:88s are safer to run, but 5:13s will give you a little more torque.
Don't waste your money on intake or exhaust.

Regear prices are all over the place. 1-2k dollars is the norm.

Ripp has a headers and tune for about 2k dollars, and although it has proven to boost horsepower and torque, I prefer my Jeep quiet. Lots of videos on youtube

I am happy with my set up(in my signature)

 

Interesting. I was not aware the 2009 non rubicon models were 3.73 only. Good to know. My tires are actually LT295/70R17 which I believe is just over 33 inches but I just feel that I need more power. The throttle lags. I just did a little research on the super chips thing. Looks the same as the aev pro cal I was reading about. So this in essence will probably give me what I'm looking for then huh? The procal chip is $150. Not too shabby I guess. I'll have to do more research then.

If anyone reads this part and can chime in more on these chips I would appreciate it. Like if there is a difference between the different ones, which one is best and if you have really gained a significant increase from using it.

Thanks

 

The AEV is not an actual programmer that will increase your HP & TQ. What it will do is allow you to adjust your tire size which will calibrate your speedo/odo and since you have an automatic trans it will bring the shifting back to optimum specs. If you are looking for added performance you can choose tuners from Hypertech, Superchips, Bully dog and Diablosport, to name a few.

I had an '08 JKU which I ran 33s and 35s with 5.13 gearing. It handled well with both tire sizes. For added insurance you can always weld on gussets on your front "Cs". With the 33s, I loved the added torque the 5.13s provided. With the 35s it was just right for my driving style.

Take it from a guy you ran 33s with the stock 3.73s, I was not impressed and dreaded driving it, even with the OD turned off. If you want that added uummpppphhhh, then you should regear. As far as mileage, I averaged 14-15 mpg city driving.

Here's a gear chart to help you decide...



A pic of my old 2008 JKU

 

thanks for the responses. regearing sure does sound like its what i want to do. Im going to spend the $150 on the procal for fun and games just to see what it does. Ill let yall know once i install it.

worse case, ill reset it and sell it i guess.

 

Changed my mind. Going with the superchips instead. Reviews sound awesome especially for automatics. Will let you know.

 

Check out the Sprintbooster as well.

 

**UPDATE**

i installed the SUPERCHIPS flashpaq 4 days ago. i have only used the 87 octane tune map so far and it has upped my MPG from 13.5 to 16.5. I no longer need to press more pedal going up hills and i can tell the shift points are different, much better. Im planning on doing the 87 octane for at least 2 tank fills, then i will try each other tune going 2 tank fills on each one so i can get a good grasp of how each performs.

in a few months, i should have a solid opinion on all the tunes available and i will go with the best one for my needs.

so far, im very satisfied with the purchase. i bought it for $315 with free shipping off of ebay. thansk for all your help, i wouldnt have ever considered doing this if not for this thread. you guys rock!! definitely no need to regear. Unless i go to 35s one day, then ill start thinking about it again depending on how it changes the ride.

 

Sorry for the noob questions, I am at the exact spot you were (based on your first few posts)... 09 sport, 3.73 gears and will need new tires by the end of summer. I want to go to a 33" tire until my kids are a little older/bigger. If a 350.00 superchips can save me 1000 or so in gearing until I can figure out if the "lift and tire" bug is going to bite thats a heck of an investment.

never used a superchips before, is it something that you plug in and leave there?