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Old 04-17-2012, 10:20 AM   #1
79 blue monster
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Wheel backspacing

Im about to look for wheels, but dont know the maximum/minimum backspacing. I have a 5.5/7.5 drop, and im gonna be running 20in wheels in front and back. What is the maximum width i can go in the front, and what is the maximum width i can go in the back? And what back spacing do i use for each? I need help !!!!
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Old 04-17-2012, 06:21 PM   #2
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Re: Wheel backspacing

anyone??????? i need help. what size are you running??? i ment to say OFFSET*****not backspacing.
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1979 GMC 3/4 ton camper special 454 (7/8in drop) UPDATE: CADDILAC 500 SWAP AND 4X4 SWAP
http://67-72chevytrucks.com/vboard/s...d.php?t=518625
1965 gmc 4x4 build : http://67-72chevytrucks.com/vboard/s...d.php?t=724972
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Old 04-17-2012, 06:27 PM   #3
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Re: Wheel backspacing

Not too many people have lowered 3/4 ton trucks. But on a 1/2 ton the rear would be 5" back space on a 10" wheel. I believe the rear end is 66" wide on a 1/2 ton too. Measure the width of your rear and go from there. As I think the rear on yours might be wider than 66". Sorry I couldnt be more help.
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Old 04-17-2012, 06:42 PM   #4
79 blue monster
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Re: Wheel backspacing

Quote:
Originally Posted by 74 stepside View Post
Not too many people have lowered 3/4 ton trucks. But on a 1/2 ton the rear would be 5" back space on a 10" wheel. I believe the rear end is 66" wide on a 1/2 ton too. Measure the width of your rear and go from there. As I think the rear on yours might be wider than 66". Sorry I couldnt be more help.
thanks, at least someone responded so that 5in backspacing, would be 0in offset right?
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1979 GMC 3/4 ton camper special 454 (7/8in drop) UPDATE: CADDILAC 500 SWAP AND 4X4 SWAP
http://67-72chevytrucks.com/vboard/s...d.php?t=518625
1965 gmc 4x4 build : http://67-72chevytrucks.com/vboard/s...d.php?t=724972

Last edited by 79 blue monster; 04-17-2012 at 06:49 PM. Reason: forgot to say something
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Old 04-17-2012, 06:50 PM   #5
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Re: Wheel backspacing

The 1/2T trucks use a 5" to 5.5" rear backspace on a 10" wheels, and the front 1 5.25" backspace on a 8.5" wheel. I would measure like 74 stepside said, and go from there. You can adjust as needed if your rearend is a little different.

Might be hard to find a "off the shelf" wheel in 8-lug that will have the backspacing or staggered backspacing for a lowered truck. Might have to look into a custom built wheel.
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Old 04-17-2012, 06:51 PM   #6
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Re: Wheel backspacing

You can run a 20x8 with a 5" BS up front.
(or 20x8.5 with a 5.25"-5.5" BS)
These are 1/2 ton numbers.

I know you want absolute answers,... but I don't have them for 3/4 ton trucks.
You need to measure your truck yourself.
Too much money involved to make a mistake.

You will also need to remove your front inner fenders or modify them.
Look at some of the other build threads and ask the members with the trucks you like.

Read this to learn how to measure for wheels.
http://www.carcraft.com/techarticles...t/viewall.html
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Last edited by lolife99; 04-17-2012 at 07:23 PM.
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Old 04-17-2012, 06:53 PM   #7
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Re: Wheel backspacing

An easy way to find out what backspace you need is to take a wheel off and support the axle/control arm at ride hieght, tape one string with weight on it to the fender lip, one on the inner fender, and one on the hub where the backside of the wheel makes contact. The strigs will give you plum line to measure from. Hope this makes sence.
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Old 04-17-2012, 07:00 PM   #8
79 blue monster
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Re: Wheel backspacing

ok thanks guys! im going to go measure right now.
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1979 GMC 3/4 ton camper special 454 (7/8in drop) UPDATE: CADDILAC 500 SWAP AND 4X4 SWAP
http://67-72chevytrucks.com/vboard/s...d.php?t=518625
1965 gmc 4x4 build : http://67-72chevytrucks.com/vboard/s...d.php?t=724972
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