34 inch tires
 

Hi guys. I have done a lot of searching and haven't really been able to get all the info I need. I have a 2008 jk x 6 speed which I am assuming has the 3.21 gears (I haven't seen a build sheet since I bought it used). There are so many opinions about driveability of 33-35 inch tires and I was just trying to see if I could get some more info and opinions from you guys that run these tires.
My plan is to run a 2.5 rough country bb lift and I have not decided between 33s 34s or 35s? From what I have read you will lose 6th gear with 33s anyways so why not go bigger. This is my daily driver and new gears would have to wait for a while. With that said I was looking at going in the middle with the maxxis bighorn 34x12.5 tire. What problems would I be dealing with compared to a 33x12.5 tire.
I also plan on getting some wheels to go with the tires. Thanks for any help, I know this subject has probably been discussed already.

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That's what I run, 34" Maxxis and 2.5RC coil lift. I have 3.73's and I use 6th when I'm on the interstate. I have been looking into regearing, but I'm not sure the cost is going to work out. I would rather get a tire carrier or other accessories with the money. In fact I think 4.10 would be just right for this, although I'm sure someone on here will tell you to go 5.13, but I think that would make 1st a granny gear. My rpm's are ~2300/2400 at 70ish mph.

e: I see it's your first post. Welcome to the forum.

OK for awhile but plan to regear
 

I also have a 6-spd with 3.21s which is in the shop right now getting 4.88s. I'm running 315/70R17 Duratracs which are nominally 34.4". On the Jeep at 30 psi, they measure 33.5". I went with a BB lift as well so I could fit gears into my budget. At first I thought, "this isn't so bad," but it was only a matter of weeks before I decided to get the regear.

On flat or slight downhill roads with no wind I could get into 5th at 45 and 6th at 55 but I was constantly dropping back into 3rd or 4th to get up the least little hill. For all practical purposes, my 6th spd was a 4spd. On the other end, starting out in 1st was a different experience, especially on a hill. It took more throttle and clutch finesse to get those bigger tires turning. What's going on at the high end is only half the issue.

The bottom line is, IMO, you can get along OK on 3.21s for awhile but should plan to regear ASAP. I went with 4.88s because my daily commute is a mix of country and small city driving with speeds ranging from 25-55 mph. If I spent a lot of time on the interstate I might have went with something higher to keep the revs down at 70 mph. Best of luck to you!

J C, I've asked you about these tires before, but what do these things actually measure, I believe the manufacturer states 34x12.2 Are they anything close to that? Also how far do they stick out past fenders?

In my 6-speed Sport, I regeared from 3.21 to 5.13 when I had 32's. Running 34's now and very happy. Re-gearing is the best thing you can do to enjoy driving your Jeep more.

X2. The first time my wife drove the JK after the regear, she said, "This thing finally has some balls." :ya:

very true- my old 07 had 488 on 33's and drove great, my new 10 still has the 373 on the same 33's and the first time my wife drove it she said it's OK but it needs gears. I see some possible 488's in my future!

I had no idea Maxxis made (or marketed) a 34" Bighorn. I run the Bighorns and they are the 315/75R/16 versions which are"considered" 35's even though that size technically measures around 34.6". I will say that the Bighorns run small so I would guess they measure around 33.5" when mounted and running at 26-28 psi. Actulally, not too different from the popular 35" KM2 tire. Most 35's will measure around 33.5" from what I've seen.

One thing to consider when deciding on your tire is what size wheel to get and what its made from. My brother in law's 35's (KM2's) weigh about 8o pounds a piece if I remember correctly and that's sitting on a steel 15" wheel. Mine weight about 98 pounds a piece sitting on a similar steel wheel but at the 16" size. While that doesn't sound like a huge weight difference on paper, there is some physics invloved that makes that weight differnece much more which can really impact the driveability.

If you decide to get a 15" wheel and stick with aluminum, you can cut down a lot of weight which may help if you don't regear. Not saying it will be perfect but every pound helps with driveability!


edit** just checked Maxxis website and I guess they do have a 34" tire. It looks to be the 12.2" width, not 12.5".

I know abunch of people who run 35's without regearing and just throw a programmer on it with a cold air intake and it runs fine. Its obviuosly a little more sluggish than factory but barely noticeable

Everyone I know who has reageared hasnt regreted it yet. You shouldnt either.