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Old 02-18-2008, 09:18 AM   #1
s_nova69
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HELP!!!!!!!!!! Is a 68 12 bolt a different width than a 72 12 bolt???

I need to know quickly if a 12 bolt out of a 68 is a different width than a 72 12 bolt???
I am trying to get my chassis done for the car show on the 27th of Fed and I think my axles are too long. Please help thanks for any insight you can shed in advance.
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Old 02-18-2008, 09:25 AM   #2
Longhorn Man
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Re: HELP!!!!!!!!!! Is a 68 12 bolt a different width than a 72 12 bolt???

the 72 would be about 3/8 inch wider on each side.
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Old 02-18-2008, 09:26 AM   #3
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Re: HELP!!!!!!!!!! Is a 68 12 bolt a different width than a 72 12 bolt???

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72 is about 3/4" wider on each side I believe.....

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Old 02-18-2008, 09:28 AM   #4
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Re: HELP!!!!!!!!!! Is a 68 12 bolt a different width than a 72 12 bolt???

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Well I only missed it by 3/8" on each side...

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Old 02-18-2008, 09:32 AM   #5
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Re: HELP!!!!!!!!!! Is a 68 12 bolt a different width than a 72 12 bolt???

I have a 68 12 bolt. Since it is not as wide as a 72, does that allow me to run less back spacing for a deeper wheel?
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Old 02-18-2008, 09:45 AM   #6
oldspowered67C10
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Re: HELP!!!!!!!!!! Is a 68 12 bolt a different width than a 72 12 bolt???

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I have a 68 12 bolt. Since it is not as wide as a 72, does that allow me to run less back spacing for a deeper wheel?
Yes. Im sure youre aware of this but a 68 is 6 lug and a 72 is 5.
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Old 02-18-2008, 09:49 AM   #7
s_nova69
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Re: HELP!!!!!!!!!! Is a 68 12 bolt a different width than a 72 12 bolt???

So Longhorn man. In theory if I bought axles, say from superior axle for a 72, the surface that the bearing rides on should be enough and it should all be fine to use the 68 rearend. Right???

Oh I have been meaning to post some picts of a 70 Longhorn that I bought out of Boise but have just been to busy. You will know it when it is up. A beautiful blue with a white top.


Thanks again
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Old 02-18-2008, 12:03 PM   #8
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Re: HELP!!!!!!!!!! Is a 68 12 bolt a different width than a 72 12 bolt???

The 71-72 axle will not work in the 67-70 rear end. Even if the bearing surface was wide enough it would move the brake drum out the difference in the width. As I recall the difference is more like one inch per side.
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Old 02-18-2008, 12:42 PM   #9
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Re: HELP!!!!!!!!!! Is a 68 12 bolt a different width than a 72 12 bolt???

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Originally Posted by oldspowered67C10 View Post
Yes. Im sure youre aware of this but a 68 is 6 lug and a 72 is 5.
I am having 5 lug axles made for it, so I have more wheel options. Thanks for the answer.
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Old 02-18-2008, 07:27 PM   #10
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Re: HELP!!!!!!!!!! Is a 68 12 bolt a different width than a 72 12 bolt???

Rear end for a late 70 on back is 56" and the late 70 thru 72 is 57 1/2" wide. If using the wider axles in the early housing, you also have to use the late 70, 71/72 backing plates, brakes and brake drums. There have been a number of threads on this subject. Try a search for more info.
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Old 02-18-2008, 10:20 PM   #11
Longhorn Man
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Re: HELP!!!!!!!!!! Is a 68 12 bolt a different width than a 72 12 bolt???

personally, I wouldn't even consider running the wider axles in the narrow brum. But it seems planty have done it and got away with it.
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