Short Box drive shaft? What fits?
 

By any chance are there any drive shafts to fit a short bed with a 402/T400 and a 12 bolt rear? Maybe something from the wrecker from some different year of truck?


Reid

I'm getting a new one fabbed this weekend by a guy who does driveline's for Busch/Winston Cup cars. It is for a '71 SWB 350/350.

All I has to do was measure from the transmission output shaft to the U-joint cup on the yoke, and run a string between those two points to measure the clearance through the hole on the crossmember (ride and drop). This is to insure that the driveshaft does not hit the crossmember when going over bumps, ect. Someone put a 3'' OD shaft in mine at one point and it did not have enough clearance through the crossmember hole...and got beat up. Very shaky, to say the least.

He is going to use the piece that goes into the trans...but everything else will be new (and balanced)...U-joints included. The new shaft will be 2.5'' OD but made of some kind of thicker walled steel that he uses in the race cars.


Total cost: $170 US. :D


A driveline shop may be the ticket you are looking for. Good luck!

350/Th350 short shaft on a SWB = 4 foot 10 inches.

So did these have a 2 piece shaft orginally?

Not trying to take this thread off topic- but who is doing that for you? I need my 2 piece drive shaft balanced. I'm getting a lot of vibration since putting in new u-joints. I'm afraid I am going to have to take it back apart to have it balanced:mad:

JP

REPO:

I've read on another thread that some had 'em...some didn't.

My particular truck shows no sign of ever having a center joint (for 2-piece) so I assume it was always a one piece unit.

The engine and trans had been swapped from a '76 ....so they might have put a different driveshaft in as well. It is probably why it didn't have the proper clearance...and got dinged up.

My truck has heavy-duty trailing arm/coil spring rear and after measuring the clearance with the rear suspension in the 'hanging' position (using the string as a centering line), the driveline tech determined that the 2.5'' would have plenty of travel room...even with a heavy load. We'll see....


I think the type of differential (and transmission) will determine the proper length of the shaft you need for your truck. When having a shaft custom built you will need to measure carefully (and twice). I measured my length and clearances 3 times...just to be sure.

I have a 12-Bolt (Corp.) and a 350 TH transmission and the distance between the bottom of the U-Joint cup (rear yoke) and the very end of the output shaft (transmission) was 62.5'' (5 foot 3 inches). Like I said, the engine and trans are not original to the truck.

cheatham,

You have a PM. :)

Yeah, your '76 tranny (if an automatic) would have the long tail shaft. Also, it sounds like it may be in the 6 cylinder/4X4 location.

"Also, it sounds like it may be in the 6 cylinder/4X4 location."

Are you refering to the engine/trans...or the crossmember with the hole through it?

The glovebox sticker shows that the truck came with a 350/350 combo...but judging from what I've run across while fixing her up I would not be suprised if the last "mechanics" who worked on her put the engine and trans in upside down. These guys were a real piece of work. :rolleyes:

i was actually refering to the engine and tranny...but after re-reading it, I realize I am totally wrong.