Hello Everyone,

I am in the process of looking for a used 4 door Unlimited X JK. It will be a daily driver with very little offroad use. It will get me to the timber during deer season and take me back through some soft corn and bean fields durning planting season and harvest. I am looking for one with an automatic transmission so my wife can drive it if she ever needs to.

One of my main requirements is that it must have atleast 373 gears in it. (I would prefer 410's) I have found a few but I am wanting to put a mild lift on it with either 33's or 35x12.50's which leads me to my question.

I was wondering, if a Jeep 4 door JK with an auto trans that has 373 or 410 gears could handle 33's or preferably 35's without a bunch of added stress to major components? What do you have and/or recommend?

Anyone with any experience in this category would be greatly appreciated! The more input the better. I want to save myself from making a wrong decision.

Thanks,

Barry
Illinois City, IL

 

My dad has a 2011 jk unlimited automatic with 373 gears and 33 and it seems under powered I would not recommend 35 .

 

If you find a used Rubicon, they have 4.11 gears from the factory, plus a lower geared low range in the transfer case. They also come stock with 32's, so 33's require nothing more than a budget boost coil spacer lift. The coil spacers come in different size lift heights, so depending in the size you get, you may look into new shocks. My fronts (before the full lift kit) were 1.75" and hhe rear was .75", and i ran 33's with absolutely no rubbing, trimming or anything. 35's would require slightly more lift, or a 1" body lift.

 

Just make sure to loosen the adjuster on the drag link (attached to pitman arm) and re-center the steering wheel after lifting any amount, or the ESP/computer will think you're in a skid, and activate, applying braking to various wheels.

 

Can't remember what thread this came from but this was a great help to me...

 

That's in the FAQ on the 'sticky' at the top of the 'Modified JK Tech' page, I believe. Posted by WoL.

 

If you are wanting to run 35's, you will want at minimum the 4.10's. Then get a programmer to calibrate the speedo and correct the shift points. And a performance tune will help restore some if the power that is lost

 

I would love to get a Rubicon but I just do not have the funds.

I really like the looks of 35's. I think 33x12.50R17's on a 4 door JK just do not look proportional. I would rather not change gears if I don't have to. Would a programmer help gain some performance back? What programmer do you recommend? Superchip? Am I going to run into added stress on the existing major components?

Thanks again!

 

Don't waste your time. Either find the cash for a re-gear or learn to live with tranny abuse and no power. 3.73's are tolerable with 33's, but just barely. Google the Grimm Jeeper gear calculator. Input all your info and you'll be able to see what works. I run 4.88's with my 35's. . .it's decent because it sees highway miles but the more time I spend on the trail, the more I wish they were 5.13' s.

Bigger tires without re-gear requires sacrifice. . .you just have to decide how much of one you are wiling to make. The only power adder worth spending your pennies on is the RIPP charger, but that's a lot of pennies. The gains from chips and intakes are so minimal it never justifies the cost.

 

Regardless of new gears or not I will need some sort of a programmer to change my shift points, correct? I am here for the people with expertise in this area because I honestly do not know.