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Discussion Starter #1
I've got a '68 Convertible with a Jim Butler 474 in it. The previous owner had changed the tranny out and was using a 200 4R built for raceing but now it's starting to slip. I don't plan on racing it at the strip and want to put the TH400 back in it. I just won one on ebay out of a '69 goat. Any ideas about drive shaft modifications I'm going to have to make? Haven't picked up the tranny yet so I'm not sure if it's physically longer than the 200 4R that's in it. Any one ever done this tranny swap?
 

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200R4 uses the 350 drive shaft but the 400 mount location. The 200R4's yoke is smaller same one as the 350. So a 400 drive shaft is needed or yours changed over to the right front yoke and length.
 

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Discussion Starter #3
Thanks a lot, I new someone here would know! I'll start looking for a drive shaft.
 

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Discussion Starter #4
I've found a 31 spline yoke for a BOP TH400. Also a complete drive shaft. Is the yoke all I need or do you know if the 350 and 400 shafts are diffrent lengths? I think the drive shaft may have came out of a Buick GS. Know if they used the same saft in the GS/GTO?
 

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GS 400TH shaft should be same drive shaft as GTO 400TH or any other Abody with a 400TH, I believe from 68 to 72. Someone correct me if I am wrong.
 

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Discussion Starter #9
Think all I will have to do is change the yoke or are the shafts different lengths? Was planning on taking it to a shop and having it balanced, I just want to make sure the drive shaft that is in the car now with the 200 4R is not too short before I go and buy the new yoke for it. Starting to collect parts now for winter projects. Snows just around the corner I'm afraid, about time to put the ragtop away for her winter nap!
 
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