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What backspacing and width wheels for 37 12.50s?

samw5

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If going from the stock 7.5 to a 9" wheel wouldn't you wanna add a 1.5 wheel spacer value to the stock wheel to properly compare?
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samw5

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Lol that was actually for my enlightenment ;)
 

samw5

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What I meant is that when you calculate how much further a tire will stick out, don't you need to take into consideration the wheel size change?

So for instance, if I'm going from a 7.5 stock to 9" wheel, that's an added 1.5".

I think I just answered my own question... the added 1.5" would affect the backspacing but in terms of comparing a 7.5" wheel with 6" backspacing and 9" wheel with the same 6" backspacing then technically speaking both should be the same amount from the inner side of the hub.
Now the 9" wheel since 1.5" large will stick another 1.5" out...

So moving to a 5.5" backspace on a 9" wheel, that would equate to 2 inches further out than stock (wheel size +1.5, + 0.5 added backspacing).

Is my math correct?
 

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Renegade

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What I meant is that when you calculate how much further a tire will stick out, don't you need to take into consideration the wheel size change?

So for instance, if I'm going from a 7.5 stock to 9" wheel, that's an added 1.5".

I think I just answered my own question... the added 1.5" would affect the backspacing but in terms of comparing a 7.5" wheel with 6" backspacing and 9" wheel with the same 6" backspacing then technically speaking both should be the same amount from the inner side of the hub.
Now the 9" wheel since 1.5" large will stick another 1.5" out...

So moving to a 5.5" backspace on a 9" wheel, that would equate to 2 inches further out than stock (wheel size +1.5, + 0.5 added backspacing).

Is my math correct?
This is exactly why I prefer to compare different width wheels using their offset rather than backspacing...I'm not really following your question well enough to do the math in my head. There are plenty of online wheel offset/backspacing calculators with visual comparisons. I would input your values and let it work for you.
 

kaeo_15

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What I meant is that when you calculate how much further a tire will stick out, don't you need to take into consideration the wheel size change?

So for instance, if I'm going from a 7.5 stock to 9" wheel, that's an added 1.5".

I think I just answered my own question... the added 1.5" would affect the backspacing but in terms of comparing a 7.5" wheel with 6" backspacing and 9" wheel with the same 6" backspacing then technically speaking both should be the same amount from the inner side of the hub.
Now the 9" wheel since 1.5" large will stick another 1.5" out...

So moving to a 5.5" backspace on a 9" wheel, that would equate to 2 inches further out than stock (wheel size +1.5, + 0.5 added backspacing).

Is my math correct?
One thing to keep in mind is that width adds equally from the center point, so +1.5” in width will add 0.75” to each side. So, if the offset is the same as stock, the 9” wheel will poke 0.75” more along with being 0.75” closer to the spring. This is also where backspacing takes into account both width and offset. The backspacing for the examples above are:

7.5” width +44 offset: 5.98”

9” width +44 offset: 6.73”
 

samw5

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Hope I didn't screw up ordering some 17x9 +12 (that's 5.5" backspacing) with 35x12.5 tires...
I'm hoping for them not to poke out too much since I'm in PA and apparently people don't like that around here...
Worse would probably them not sticking out far enough and rubbing inside.
 

kaeo_15

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Hope I didn't screw up ordering some 17x9 +12 (that's 5.5" backspacing) with 35x12.5 tires...
I'm hoping for them not to poke out too much since I'm in PA and apparently people don't like that around here...
Worse would probably them not sticking out far enough and rubbing inside.
It won’t poke much at all. Would be a lot less with 11.5 inch wide tires. AEV wheels are 17x8.5 +25, and are tucked under the fender pretty well. I run 17x9 +18 37x12.5r17 and have very little poke in the back and a little more in the front (wider axle). So, you will have 6mm more poke than I do. Here is your new setup compared to stock Rubicon on the calculator.

Jeep Gladiator What backspacing and width wheels for 37 12.50s? C2FADB30-4685-4081-A271-558D095DE0CE
 

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samw5

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So you have a pic of the front?
I was hoping for it to stick out just a tad so I think I should be on the money.
Hope I don't get inner rub but hopefully the teraflex 1.5 should help a little with that too.
 

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Hope I didn't screw up ordering some 17x9 +12 (that's 5.5" backspacing) with 35x12.5 tires...
I'm hoping for them not to poke out too much since I'm in PA and apparently people don't like that around here...
Worse would probably them not sticking out far enough and rubbing inside.
Should look about like this:

Jeep Gladiator What backspacing and width wheels for 37 12.50s? C5F5C35F-0D7E-4BE0-B4A8-8AA8FBC43E4C
 

kelkolb

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Hope I didn't screw up ordering some 17x9 +12 (that's 5.5" backspacing) with 35x12.5 tires...
I'm hoping for them not to poke out too much since I'm in PA and apparently people don't like that around here...
Worse would probably them not sticking out far enough and rubbing inside.
What trim? On a Rubi or Max Tow that should be a great wheel spec. Could potentially rub on a narrow axles trim.
 

Jocww

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So I am going with the mopar lift on my JTRD will the stock wheels work with 37s without rubbing? Or will I have to go aftermarket for wheels when I get back to ca?
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