14 bolt SF Swap - will the driveshaft fit?

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Mattchu60

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Hey All, I am knee-deep in my 14 bolt swap, almost have the new 10-bolt front rebuilt and starting on the rear end today.

A major question has come up and I cannot find a strait answer.

I know I need the trick u-joint for the driveshaft, but what about the driveshaft length? Does it need to be shortened? I hope not!

I cannot find a strait answer on the web, some say it does need to be shortened, others report no issues.

What will I need to expect? I was hoping to swap everything in the next few days.

My truck is not lifted, has stock suspension. Its a K10 now, will be putting the 3/4 ton axles from a 87' k20 into it. SF 14 rear and 10 bolt front, both with the HD brakes (8,600lbs truck).

Also, can I get the trick u-joint at Advance or O reillys?
 

crazy4offroad

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EDIT: just noticed the title 14 bolt SEMIfloat, disregard this post
 
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bucket

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The stock shaft will work. I got the #447 conversion u-joint at Napa.
 

Mattchu60

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I measured them best I could a moment ago, they seem to be close. The 14 bolt may be 1/2-3/4" longer, but its hard to get an exact reading due to the pumpkin.
 

Mattchu60

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Got the rear end installed tonight. Driveshaft fits just fine, no issues. Thanks to all for the information, I used the 447 ujoint from Napa and it worked great.

Waiting on the front end as Tirerack shipped the wrong lugnuts for my truck. Need to call them in the morning, hopefully I can get the right ones fast.
 

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