2 piece driveshaft or not

[56hotrodred]

I am using a 1980 1/2 ton frame under my 56 and it came with the 2 piece driveshaft and the steady bearing in the middle! Also came with a Chevy truck 12 bolt which I am thinking on getting rebuilt with posi gears, probably 3.42 or 3.73.

My question is should I keep the 2 piece drive shaft or get a new 1 piece one built. I have shortened the frame by 2 1/2 inches so even the 2 piece one would need modification.

Right now I am finishing cleaning the frame before I sand blast it and paint it with the cab and box removed. This is a good time to cut the rivets for the centre steady bearing mount if I am going to do it.

Thanks much in advance.

[1-ton of fun]

for a shortbed truck i'd go 1 piece for sure

[Jemezcrusher]

Yep. Depending on the tranny, should only need about a 50-52" drive shaft.

[56hotrodred]

I was thinking about the 700r4 transmission.

[Jemezcrusher]

I used a 700R with an 8.8 in my 55 210. Have a T5 and 8.8 in my 50 3100 and looks like will be the same exact length shaft at 51 inches. Just measure from center to center at the u-joint caps on the yokes. Ordered mine from Southwest speed on Ebay for 200 bucks

[1project2many]

Long wheelbase trucks and higher driveline angles like found in lifted trucks can see benefits if the angle is split across multi-piece shafts. Otherwise stick with a single shaft.

[56hotrodred]

Thanks all very much for you replies. I have removed the steady bearing mount in preparation for ordering a new driveshaft. It is a little ways out but it was much easier to cut those rivets out now with body off.

[dsraven]

If in doubt, set truck on groundor drive it up onto some blocks so it is at ride height. Then cut a length of 1x4, or other that you have laying around, to be the length from diff yoke to trans tailshaft. Now jack the rear of the truck up until the shocks bottom out. Check to see if the board will still fit and not be too long. Now let it down off the jack and put enough weight on the rear of the truck to bottom on the suspension snubbers, get some friends who can sit on it or something. Then check the board length again. Thay way you will know for sure if the length of shaft will bottom out in the trans or seperate from the trans when the suspension travels. The slip yoke lenght only allows for so much and too much travel wears out the tailshaft bushing and seal.