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Discussion Starter #1
In a nutshell, I have a completely stock 99 TJ. 4.0-5speed
Purchased in 2003, The dealer had put 30-9.5-15 BFG All terrains on it. Fast forward to yesterday, Finally put new tires on, no one makes the 30-9.5-15 any more so i went to a 31-10.5-15.

I rub on the control arm during turns, which leads to my next question. Does anyone know the rim size, more specifically the offset? I don't want to do spacers, was thinking if I did a new rim with a more positive off set, it would move the tire "out" the 1/2-3/4 of an inch that I am lacking.

If that doesn't work, I will put on 255/75/15 which are almost the exact same as the 30-9.5-15
 

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the simple fix is to add a washer to your steering stops. its probably the easiest mod i've ever done to a vehicle. https://www.stu-offroad.com/steering/stop/steerstop-1.htm

If you do want new rims, focus on back spacing and forget you ever heard of offset. for a 31" tire you'd be looking around 4.5" of back spacing on a 15"x8" rim. if you ever wanted to go to a larger/wider tire its recommended to go with a 15"x8" rim that has 3.75"-4" back spacing
 

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Id also find a new tire store to deal with being they told you nobody makes a 30x9.50x15 anymore. There is 3 pages of them on DT's website. everythig from BFG to Yokohama, you name it.
 

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+1 to the steering stop adjustment suggestion.

If your tires barely rub this is the easiest and cheapest solution. When I bought my 01 Sport used the PO had put 31x10.5R15 tires on it and they rubbed the lower control arms at full turn. One washer behind each steering stop eliminated the rub and the very minor loss to turning radius isn't even noticeable.
 

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BFG shows both the A/T KO2 and the M/T KM3 available in that size.

I can't find anyone that has 255/75R15 tires.

For BFG they only make two metric sized in the KO2 for 15" wheels, 215/75R15 and 235/75R15. They make 6 inch sized tires, the 30x9.50R15 and 31x10.50R15 along with 4 taller and wider tires.

Goodyear on the other hand only makes two 15" tires in Duratracs, the 31x10.50R15 and the LT235/75R15 (29" tall) sizes.

This reminds me why I stayed with 16" wheels when I put new wheels on the Rubicon. I had considered 15" wheels, but I wanted Duratracs and the extra width of the 31x10.50R15 tires I didn't want, so I stuck the the OEM size of LT245/75R16.
 

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Discussion Starter #6
BFG shows both the A/T KO2 and the M/T KM3 available in that size.

I can't find anyone that has 255/75R15 tires.

For BFG they only make two metric sized in the KO2 for 15" wheels, 215/75R15 and 235/75R15. They make 6 inch sized tires, the 30x9.50R15 and 31x10.50R15 along with 4 taller and wider tires.

Goodyear on the other hand only makes two 15" tires in Duratracs, the 31x10.50R15 and the LT235/75R15 (29" tall) sizes.

This reminds me why I stayed with 16" wheels when I put new wheels on the Rubicon. I had considered 15" wheels, but I wanted Duratracs and the extra width of the 31x10.50R15 tires I didn't want, so I stuck the the OEM size of LT245/75R16.
The issue is im away for work, the wife had a flat and took it to the only open tire shop. It is used as a spare vehicle/child training vehicle at the moment. (I am kind of proud that all my kids can drive stick) When the last kid goes to college I plan on tearing it down and redoing everything.
 

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Ah, the old mechanic sees the lady and sees $ sign syndrome. Maybe I'm being unkind to the tire guy, but I have seen too many blow smoke up a customers rear, including mine. There was a tire dealer here that gave me good service when I was here the first time in the late '70s. (Then got transferred to Va and then back in '89).

When I got back the management had changed and they were very adept at blowing smoke. They tried it with me and I left and never went back. Not surprisingly with a year or so they had shut down. That's when I went to the tire dealer I have done business at for 30 years. Interestingly the shop manager is a female and she has forgotten more about tires than I will ever know. She also tells it like it is and works with the customer. Their techs even use a manual torque wrench when the put the wheels back on the vehicle. They have a large component of their business is local and over the road delivery trucks and the Sheriff's patrol cars.

What's done is done, you will lose a little bit of turning radius, hopefully the tires are a good name brand and you have many good miles with them. You will want to check and see how much the speedometer is off and decide if you want to change the gear.

Generally speedometers are a little optimistic. If, as I believe, the original tires on the Jeep were P215/75R15 (28" tall), then the tire revolutions per mile were 755. If the speedometer was a little optimistic, say reading 60 when the Jeep was really doing 58. Then increasing the tires slightly to the 30x950R15 means the rev. per mile for the tire is actually 708 now or about 7% less. So now at 60, your actual speed would have been 62, not enough to really notice, unless you encounter a zealous cop.

But now you have 31x10.50R15s and the rev. per mill is 677. Now the actual speed when the speedometer reads 60 is closer to 65. Just allow a bit more cushion when your driving. If you have a hand held GPS or an app on your phone, you can nail it down closer.
 

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from my experience the OEM jeep configuration seemed to be more accurate with 31" tires. but those are all late model jeeps with the 42RLE trans. YMMV. at least now everyone has a gps tracker on their phone and can easily tell the actual speed. luckily the speedo gear is another very easy task
 

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Discussion Starter #9
Ah, the old mechanic sees the lady and sees $ sign syndrome. Maybe I'm being unkind to the tire guy, but I have seen too many blow smoke up a customers rear, including mine. There was a tire dealer here that gave me good service when I was here the first time in the late '70s. (Then got transferred to Va and then back in '89).

Well actually it was WE (the store) dont carry any 30-9.5-15. I will say the wife went and did what she does, and we wound up with 255/75/15 General grabbers. It will work for the next couple of years.

The plan is once the youngest masters the stick shift, the Jeep becomes mine.

At that point my plans are 4 inch lift, 33s, and a regear to 4.88s. along with a complete engine tranny rebuild.
 

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A 4" lift is a bit extreme for 33" considering that the Rubicon came with 31s and no lift. A 2" lift would be more than enough, considering that half the increase is below the axle. If I were going with 33s, I would probably put 1" pucks on and call it a day. But then I'm also in the flatlands of S. Georgia.
 
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