Wheel Backset

Starting out wrong! I purchased a 1999 cherokee, added a 3" Rusty"s lift, purchased 31x10.50x15 tires and had them mounted on AR-23 American Racing 15x8 rims. Well now the tires rub the fenders "big time" in the front when turning. I ordered the wheels per year/model! These wheels only come with a 3.75 back set! I am new at this and would never have thought about that being a problem! I want to keep the stock fender flares. What is the answer? What size tires can i put on these wheels and not rub? Please help before i mortgage the house on this project.  

5"...  
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"Scrub Radius". The distance measured from the center line of the wheel width to the steering knuckle.

As the scrub radius increases (less back space), the tire moves through a greater arc when turning, which causes the tire to contact the fender.

By increasing the back space, it will move the wheel/tire further inside the fender opening, and reduce the scrub radius. Then the same width tire will not rub the fender.

"Offset", "Back Space" and wheel diameter are all inner related. You can't change one without affecting the other.

For your 10.50 tire/vehicle combo, the wheel should be 7" diameter, close to zero or positive "offset" and 4.75"-5" "Back Space". Your wheel specs are way off.

Back Space and Offset ARE NOT THE SAME THING. The same back spacing will produce different offsets depending on the wheel construction and wheel width. Get the full spec sheet for any wheel you choose so you will know the offset and the back spacing.

The wheel "Offset" which affected the "scrub radius" is causing your tire rub. It's not the tire width (alone).  

Pick a style of wheel, then check the sizing. If it does not come in the "right size", keep looking.

It's frustrating, I know. But, after-market wheels are made to "fit" nothing and "go on" everything.  

Thanks, so do i "scrub" the tires or the wheels? I now understand the back spacing and off set lingo. Is there a tire i can put on these 15x8 wheels or do i look for new wheels? I bet i am not the only one that has run in to this problem!  

New wheels, without question. Your tire size is perfect for your vehicle and lift.

Do you have your stock wheels? Put the tires back on them if you do. They will fit great and you will see what a difference offset can make.

Then go wheel hunting. Remember, it's "offset" your trying to address. When sizing the wheel, here is the order of importance. And this is based on the fact you already have the tires.

Wheel diameter & bolt pattern (given), offset (-5mm - +15mm), width (7" or 8"), back spacing (5" or less).

Don't "filter" by back spacing, just know what it is. If it is 5" or less you will not have tires rubbing on your springs and spring pockets.  

Thanks for the help.  So for an 8x15 wheel i need to stay in the 4.5 to 5 inch range? Need some AR 23 8x15 wheels! Just for the record i was specific when i asked the folks at "Buy Wheels Today" if these wheels would work and even wrote it on the order. Of course they did not even ship the wheels to the correct location that i had written on the order! I guess they just wanted to sell wheels today!  

The AR23s come in a 15x7 with a -6mm offset. That is very close. Might work with 10.50 tires, but no promise. (Clearance wise) (The tire will fit the wheel)

Your wheels have a -19mm offset. Both the 15x7 and 15x8 have a 3.75 back spacing. See what I mean.

The -6mm offset wheels will give you .5" more clearance through the turning radius than the -19mm offset. Is that enough?  

Yeah, it all makes sense now. I wish i had researched better at the beginning. I like the little off-set look as compaired to the stock wheels but do not want to make a mistake twice. It seems to be no problem to find the correct bolt pattern but then be careful! I will maybe take your advice and put the tires on the 7" stock steel wheels and continue my search.
Thanks for all the help!I will definitely come back here for more advice.  

Before you mount up the tires on your stock wheels, measure the the back spacing.

If the tires are removed:

Lay the wheel FACE UP on a flat surface. Measure from the flat surface, through the center cap hole, to the bottom side of the wheel mounting surface.

If the tires are still mounted:

Lay a straight edge across the backside of the wheel lip, making sure it does not contact the tire. Then, measure from the wheel mounting surface to the bottom edge of the straight edge.

What is it?  

I will check that when i get home to Va. In Detroit today earning a living to pay for those wheels! Does not look like shopping for the wheel style i want and keeping the Cherokee stock (fender flares) is going to be a piece of cake. The motion of using those Ar wheels was inspired by the many pictures on the net i saw: "3" lift, 31" tires, 15x8 wheels, sounds easy, Maybe some of those guys need to state how bad their tires rub!  

I have an '01 Lightning and an '07 Escalade. Neither has the wheels I wanted because of fitment issues. I went with my tire choice first and then got wheels that worked. But they were not the wheels I really wanted. Try buying wheels for any new GM truck. They don't exist (Yet, I hope). No Sympathy.

I'm running Black D Window Steel wheels on my TJ that are custom offset from U.S. Wheel. Cheap to buy, $60, but they come bare steel. Then $70 to have them powder coated.  

Why 15x8? I ran 33x10.50 for years on my AR Stic5 15x7 wheels for my TJ. You will be more successful in your wheel search if you include 15x7. They are fine for a 10.50 tire.  

yep, 10.5's belong on 7" wheels...  
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