Driveshaft length

03teej

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Getting ready to pull the trigger on a Currie Rock Jock 4" lift (CE-9801HS)
I need to get a new rear DC shaft. Plan to do a TT but not right now, was wondering if the driveshaft would still be right length after TT
 
The distance between the pinion yoke and the transfer case yoke would increase by a few inches installing a TT.
You can either guessimate the distance between the yokes by adding a couple inches or just wait until you have the TT installed and measure the distance between the yokes for the correct length DC driveshaft.
Personally I would wait and measure the distance between the yokes with the TT installed.
This would save you the trouble of returning the driveshaft to change the length or running a driveshaft that is a little short.
 
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The Tummy Tuck will affect the length by maybe an inch. It can be calculated here https://www.calculatorsoup.com/calculators/geometry-plane/pythagorean-theorem.php. Drive shaft length is hypotenuse. I don't know what side a is going to be in your vehicle so I used 8 inches as an educated guess, it might be less than this but you can measure. If side a (the vertical height difference between your yokes) is 8 inches before the TT then the TT increases that to 10 inches, the length of the shaft (hypotenuse) will increase by about an inch. Use the calculator above and some easy measuring to figure out exactly what it will be. Or measure your yoke to yoke length now and your vertical height difference is now and tell me what those numbers are and I'll do the math. :)

So what should you do? If the yoke to yoke shaft length is currently 16" or more you should order the shaft with our X spline and XC slip yoke then add 1/2" to your length to lead the target a little. In that scenario your drive shaft length will never be more than 1/2" from a perfect fit and the XC slip/spline combo can easily accommodate that.

Or, worst case, as @cpwolf noted above, if you get a shaft from us and need it lengthened we can do that relatively inexpensively.
 
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Thanks guys, I'll do some measuring after I get lift in and see where I'm at. I might just do the TT now too, hopefully the wife doesn't make me sleep out in the garage with the jeep
 
Does anyone know the part numbers for rancho 5000 shocks needed for 4" also have a 1" BL
 
Check this out! How much vertical change affects drive shaft length is a pretty common question, this thread inspired me to create a calculator to help answer this question. It's basically the Pythagorean Theorem I linked previously but this time it is in a hand calculator that is purpose made for determining changes in drive shaft lengths. Calculator is at the bottom of this page:

https://4xshaft.com/blogs/general-tech-info-articles/driveshaft-length-after-lift
 
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Check this out! How much vertical change affects drive shaft length is a pretty common question, this thread inspired me to create a calculator to help answer this question. It's basically the Pythagorean Theorem I linked previously but this time it is in a hand calculator that is purpose made for determining changes in drive shaft lengths. Calculator is at the bottom of this page:

https://4xshaft.com/blogs/general-tech-info-articles/driveshaft-length-after-lift