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Old 01-07-2013, 09:31 PM   #1
2wd73blazer
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Will 20x9.5 with +25 offset fit the front?

I have a 89 1 ton crew cab. I found a set of 20x9.5 rims with +25 offset. I need to know if they will fit and look right without scrubbing. If im thinking right thats about 5.75 in of backspacing on them. Anyone know?
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Old 01-07-2013, 09:35 PM   #2
f.monroe
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Re: Will 20x9.5 with +25 offset fit the front?

If its a true 9.5" wide wheel then a +25 mm offset will make it 6.25" of backspace. I do not know if it will fit but that's the backspace.
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Old 01-07-2013, 10:33 PM   #3
2wd73blazer
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Re: Will 20x9.5 with +25 offset fit the front?

Thanks. I didnt know exactly how to figure backspacing. How do you find it when they give you offset?
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Old 01-07-2013, 10:59 PM   #4
f.monroe
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Re: Will 20x9.5 with +25 offset fit the front?

A wheel that is advertised at 9.5 inches is actually 10.5" measured from the outside of the wheel . The beads are usually about 1/2 inch each on aluminum and the same on steel wheels because of the rolled lip. The centerline of the wheel would be exactly one half of the total width so that makes the center of that wheel 5.25 inches (10.5 divided by 2). That is what you add or subtract from. If its a positive offset you add it to the center measurement. 5.25"plus 25 mm which is the offset. One inch equals 25.4 mm so I just added the 25 mm (or one inch) to the cent measurement. 5.25"+1" equals 6.25 inches of total backspace. If its a negative offset wheel you subtract so if it was -25 mm offset it would be a 4.25" total backspace .
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Old 01-08-2013, 12:51 AM   #5
2wd73blazer
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Re: Will 20x9.5 with +25 offset fit the front?

Thanks. I see where i made my mistake now. I didn't factor in the rolled lips.
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Old 01-08-2013, 03:28 AM   #6
lolife99
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Re: Will 20x9.5 with +25 offset fit the front?

Google wheel offset chart in Google Images.
There are tons of charts that show offset vs backspacing on the Internet.
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