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ANOTHER Rockridge4wd Creation!! Spare Tire Carrier Delete Cess Recovery Gear Snatch Tow Strap OffRoad @ ROCKRIDGE4WD15 x 8 Black D-Window Steel Wheels Set of 4

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Unread Yesterday, 09:23 AM   #1
mic6
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Backspacing quick question

Hello folks,

Quick question. If I replace my TJ OEM steelies (15x7 with 5.5 BS) with Ravines (15x8 with 5.5(?) BS) are the tires going to stick out 1/2" more? Tire will be the same (31x10.5x15).

I thought 15x8 Ravines had 5.25 BS but I keep reading that they have the same 5.5 as the 15x7 ones.

Thanks

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Unread Yesterday, 11:37 AM   #2
irnmadn88
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Rough illustration.

If BS is the same, the | marks the wheel mounting surface (WMS) which would be in the same location. Axle side is to the right.

-[--|-----] = 15x7

[---|-----] = 15x8
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Unread Yesterday, 03:39 PM   #3
JeeporJag
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I think... That if the wheel is one inch wider with the same backspacing it’s going to stick out ½ more and in ½ more.
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Unread Yesterday, 03:47 PM   #4
BigRodney
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If the backspacing is the same and the wheel is an inch wider then it's going to stick out an inch farther. Inside remains the same.

https://www.rsracing.com/tech-wheel.html
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Unread Yesterday, 05:58 PM   #5
JeeporJag
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Thanks for the correction BigRodney. Back spacing is "back spacing".
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Unread Yesterday, 06:16 PM   #6
irnmadn88
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Quote:
Originally Posted by BigRodney View Post
If the backspacing is the same and the wheel is an inch wider then it's going to stick out an inch farther. Inside remains the same.

https://www.rsracing.com/tech-wheel.html
The wheel will but not necessarily the tire.

The tire is centered on the wheel.
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Unread Yesterday, 06:27 PM   #7
BigRodney
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Quote:
Originally Posted by irnmadn88 View Post
The wheel will but not necessarily the tire.

The tire is centered on the wheel.
Yea I see what you're saying, tire is 10.5", hangs over some on either side, going to a 1" wider rim, might not end up with a full 1" wider. Let us know the results!
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Unread Yesterday, 11:49 PM   #8
mic6
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Thanks guys!
It is confusing isn't it?

So, 31x10.5x15 tires on stock suspension have more chances to rub on ravine wheels (15x8) than they do on oem steelies (15x7), correct?
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Unread Today, 06:36 AM   #9
irnmadn88
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Quote:
Originally Posted by mic6 View Post
Thanks guys!
It is confusing isn't it?

So, 31x10.5x15 tires on stock suspension have more chances to rub on ravine wheels (15x8) than they do on oem steelies (15x7), correct?
No.

Sticking with the same tire and switching wheels from 15x7 (5.5 BS) to 15x8 (5.5 BS) the tire is going to move out AWAY from the frame.

The change in wheel is changing where the centerline of the tire is relative to the centerline of the wheel.

How much more the tire will stick OUT = less than inch.
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Unread Today, 03:35 PM   #10
mic6
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Quote:
Originally Posted by irnmadn88 View Post
No.

Sticking with the same tire and switching wheels from 15x7 (5.5 BS) to 15x8 (5.5 BS) the tire is going to move out AWAY from the frame.

The change in wheel is changing where the centerline of the tire is relative to the centerline of the wheel.

How much more the tire will stick OUT = less than inch.
So ravines have less chances to rub than steelies ??
Or same?
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Unread Today, 03:50 PM   #11
irnmadn88
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Quote:
Originally Posted by mic6 View Post
So ravines have less chances to rub than steelies ??
Or same?
Less.

The Ravines will move the tire out away from the frame and control arms.

Something like a half inch or so.
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