How to measure your driveshaft correctly?

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82sbshortbed

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When I pulled mine out it's been beat to **** and is dam near impossible to remove the ujoints. But, I have another one my neighbor gave me a couple of years ago. Now I need to know if it will fit and hopefully can go with that one. If not may just buy a new one.

This has 3 different ways to do this in this article. I don't know which is correct way.

https://www.yourmechanic.com/article/how-to-measure-driveshaft-length-by-dave-crowley

Hopefully someone can help me out here.. I know this isn't correct but,, I measured from outside of the ujoints and got 59 5/8" or about that.

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If I subtract the ujoints hole size from one end that would put me on center of ujoints holes? Right?
 

Blue Ox

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Correct.
 

Keith Seymore

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U joint(s), center to center is how i do it

This.

But - if you have a shaft made the manufacturer will probably have a specific way they want it done, and will make you go back and re-measure it their way.

And then still make it too short.

Or so I'm told.

K
 

Keith Seymore

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When I pulled mine out it's been beat to **** and is dam near impossible to remove the ujoints. But, I have another one my neighbor gave me a couple of years ago. Now I need to know if it will fit and hopefully can go with that one. If not may just buy a new one.

This has 3 different ways to do this in this article. I don't know which is correct way.

https://www.yourmechanic.com/article/how-to-measure-driveshaft-length-by-dave-crowley

I know this isn't correct but,, I measured from outside of the ujoints and got 59 5/8" or about that.

If I subtract the ujoints hole size from one end that would put me on center of ujoints holes? Right?

If you go from one edge of a u joint and then the same edge of the other U joint you don't have to do the math (you can read the correct result directly).

K
 

Bextreme04

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If you go from one edge of a u joint and then the same edge of the other U joint you don't have to do the math (you can read the correct result directly).

K

Well, only assuming you have the same size u-joint on both sides, which is not the case on my truck
 

DoubleDingo

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I'm a center to center measurer, and the times I have to get a driveline built I gave them the measurements as center to center, and they made it correctly and it fit perfectly.
 

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Accurate measurement would be center to center, but if you have both driveshafts, couldn't you just set them side by side and measure/compare?
And make sure the u joints are same cup dia/length/style. You can get adapter u joints though in common sizes if necessary.
 

82sbshortbed

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I'm gonna check them when I get home from work. I have the other one under the truck with the yoke in the transmission because it was leaking oil when I pulled it out. Lol
 

82sbshortbed

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No question they're not the same length. Lol

Guess I'm buying a new one.

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Preston Tucker

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No question they're not the same length. Lol

Guess I'm buying a new one.

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just get it cut, its not that much if you use the old ends.
 

82sbshortbed

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just get it cut, its not that much if you use the old ends.

The ends are beat up that's why I need a new one. Summit couldn't find one fir me. I'm having a hard time finding a new one.
 

82sbshortbed

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Center to center is about 58 1/4 -5/16" give or take 1/16.

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So you don’t have a drive shaft and need one made. How much movement do you give the slip yoke at the transmission before you measure from trans yoke to diff yoke?
 

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@82sbshortbed,

It looks closer to 58 3/8" to me. But I agree to cut it off, use center to center and weld it. When you say the ends are beat up are you talking about the u-joints need replacing? And as far as the slip yoke, you're measuring to the center of the slip yoke u-joint anyway aren't you? That is your shaft that you are showing with the slip yoke on it isn't it? Or is the short shaft the one that came out of your truck?
Did someone take a hammer and beat the hell out of the part that the u-joint goes into, the straps that hold the u-joint? Use the u-joint ends of the other shaft. Or, yeah, just to avoid the hassle buy another one. But you said you're having a hard time finding another one? A shaft shop will have it, or they will make you one. That's my opinion is to measure center to center, but ask the shaft shop how they want it done to.
 

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