Author Topic: driveshaft length when going from 3spd to th350  (Read 1269 times)

Offline 4chevyman

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driveshaft length when going from 3spd to th350
« on: June 21, 2009, 07:56:05 PM »
I've got a 76 lwb that had a 3spd and I am thinking about putting a th350 in.  I've got a long tailshaft 350 out of a 78 lwb.  i measured both trans and the 350 was about 3 in longer i think.  anyway i know they are different lengths.  the driveshaft is gone out of the 78, so can i go to the junkyard and get the first section of an auto driveshaft or do i need the whole driveshaft or can i use a shortshaft trans with my manual driveshaft?

Offline zieg85

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Re: driveshaft length when going from 3spd to th350
« Reply #1 on: June 21, 2009, 10:43:33 PM »
I did that very same swap in a 79 I had.  The truck I got the trans out of was a 78 and it had a single piece drive shaft as opposed to the 2 piece with carrier bearing in the 79.  Everything bolted up fine and I was on my way.  I had to tweek the exhaust pipe because it rubbed with the single piece shaft but no biggie. 
1985 C30 Custom Deluxe Ext. cab 5.7L TH400 3.21 
1985 C20 Scottsdale 7.4L 4 speed 3.21
1986 C10 under construction