Another Driveshaft Question

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Kilian

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Looking to swap a 1975 14 bolt FF into an 83 K2500 that has a 14 bolt SF, 350 V8/TH400/NP208 setup. From doing research on this site and in the parts catalogs, it appears that the current semi-float driveshaft is shorter than what is needed. I think.

Just wondering if a driveshaft that would fit this application (TH400/NP208/FF) exists in the wild without fabrication? Maybe I'm overlooking something from the late 70s when the TH400/208 was coming in and FF were still in 3/4 tons.

Please point me to any existing threads if this topic has been horse whipped in the past. Thanks!
 

Craig 85

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K30 SRW
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454/TH-400/NP205
I googled this, so someone correct me if I'm wrong. The 84-86 K30 Military (CUCV) trucks had this set up. I will make an assumption one would fit out of those trucks without issue.

"What transfer case is in CUCV?

All models used the NP 208 aluminum case, chain-driven, transfer case except the M1028A1 and the M1031, which was a chassis cab."

You may check with Boyce Equipment.
https://www.boyceequipment.com/
 

Kilian

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Thanks for the info. Did any non-military K30s from that period have the same TH400/NP208/14FF setup as well, or did the K30s come with the NP205 instead? I'm going to guess that the 205 and 208 call for different shaft lengths...
 
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BKING33

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My CUCV has a TH400, NP208, and 14 full floater. Ill try to get a measurement tonight when I get home from work.
 

BKING33

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Driveshaft is 54 3/8" length from centerline of joints
 

Kilian

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Thanks for the info. I've got a CUCV driveshaft ordered from Hillbilly Wizard.
 

Craig 85

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1985
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K30 SRW
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454/TH-400/NP205
Thanks for the info. Did any non-military K30s from that period have the same TH400/NP208/14FF setup as well, or did the K30s come with the NP205 instead? I'm going to guess that the 205 and 208 call for different shaft lengths...
I believe all the civilian K30's of this era had the TH-400/NP-205 set up.
 

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