Projects TH350 Swap Question for 58 Chevy

^^^^I think you have your answer why the 9 inch extension housing TH350 was used, along with a one piece driveshaft. If you don't want to have a new driveshaft made, or try to find one that will swap using the 6 inch extension housing TH350, then it's time to swap output shafts and extension housings, and keep the existing driveshaft.^^^^ I am Butch/56sedandelivery.

 

Did you try taking the springs out and jacking the rear UP?

 

But as mentioned before...you changed the tranny, right?

So how did you get the driveshaft out then?

Reverse the process....

 

With the new info about the one piece driveshaft, you need the long tail shaft transmission. That is why gramps went to the one piece shaft. With the short tail shaft you will probably need to go to a 2 piece driveshaft due to interference with the X frame. Gramps knew what he was doing when he built it.

 

I don't think there is any way you can run a one piece drives shaft in a 58 Chevy, there should be 2 bolts that run up in the X of the frame that mount the carrier bearing in place! Remove those blots and the drive shaft should be easily removed.

 

I am curious , you said you changed the tranny. How did you get it out without taking the drive shaft out ? Or did you just pull it back far enough to change the transmission ? I would have done what Squirrel said and swapped the output shaft. A transmission shop would have charged you a couple hundred bucks or I would have done it myself.

 

I have to agree with Dick Stevens. I don;t see a a one piece drive shaft working.

 

Think this is possible. Long tail, maybe a little relief at the X, ...NO Gabriel Hi-Jackers LOL. Could work.
But I think we're being BS'ed or spun a bit.
Let's see..We went in there and found out it's all re-built, but we can't change the output shaft??

 

A one piece driveshaft worked with the long tail shaft transmission, so why change what works. Swap the tail shafts on the 2 transmissions and put it back together the way gramps built it. I worked that way before, why change what is proven to work?

 

I'm pretty sure that you would have to relieve so much in the X that the frame would no longer support the car!

 

There are threads here where guys say they've done it.
The o/p says it's already there. He apparently does have a 58.
Of course, he says he changed the trans without removing the driveshaft, so...??

 

I'll just leave it at, I would have to see it with my own eyes to believe it! His posting doesn't make me confident he knows whether or not it is a one piece or two piece driveshaft. General Motors didn't put in the two piece driveshaft just for the hell of it. Wish you were close to me so we could crawl under my 58 and then see if you still believe a one piece would work.

 

There are conversion, one piece shafts out there, but it requires the "X" member to be modified. You tend to see it more with the 62-64 X-frame cars that run on the drag strip. I still think Gramps knew what he was doing when he put the car together, but we'll never know for sure unless photos are provided. JMO. I am Butch/56sedandelivery.

 

Ok sorry I was in Mexico for a few days and had no internet. Yes I swapped tranny's with the drive shaft pulled back and resting in the X-frame tunnel. Also I am can confirm it is a one piece drive shaft cause it won't bend in order to pull it out through the rear as a two piece would have worked perfectly. I will try to submit some photo's tomorrow. Also I have been calling around to get bids for extending the shaft. How is a shaft measured? the actual tubing itself from weld point to weld point is 52 inches, but I don't know if you include the U-joints and yoke or not.

 

Never noticed a carrier bearing and the shaft is one piece. I will get pics ASAP

 

Do yourself a favor and don't spend any money yet. You just might have a real problem by making that shaft 3 " longer.
Do this:
Put the rear of the car up on jack stands.. on the rear end housing tubes. (ride height). Put the short shaft into the transmission all the way until it stops. Pull the shaft back out, 3/4 of an inch. Line the the back of the shaft up to the pinion flange, as close as you can get it , by eye. Use another jack stand or wooden blocks, or similar.
Now , take a picture of the clearance between the driveshaft and the back of the tunnel, at the bottom. Or slip something in there like paint sticks, and measure them.
Show it to us here.

 

Johnny, Most driveshaft guys I ever knew would show you to the door, if you ever came in with something like this.
We're not building a custom race shaft here. This is basic, every day stuff.
We'll address the length when need be.
BTW, driveshaft measurements are traditionally , from center of U-joint , to center of U-joint. (cross to cross).

 

^^^^^ To each his own. Most shop's I know won't accept CL measurements.

 

Here are some basic photo's under my car showing my drive shaft.

 

See the pics?

 

Why re invent the wheel, swap the transmission tail shafts and you are done, you know it will work. It worked when gramps had it!!

 

Not the one I asked for.
Agree with BJR.
Surely someone in Lancaster, Ca, would change that output shaft over for a couple of hundred bucks.
What do you suppose a re-done shaft with a new tube would cost? Plus the clearance issues, with a longer shaft??

 

I am questioning if the OP is clear on what a 2 piece shaft is. In the pics.... why is the front shaft caked with dirt and grease and the rear is not? Isn't there a splined slip shaft in the center?

 

Depends on your area, I got a shaft made in Cali and a few here in N.Y. and they all wanted the measurement from back of tail shaft housing to yoke on rear like in that diagram.

 

I understand all that, if you're buying a complete new shaft. They need something to go by.
I would always tell the shop what I wanted and needed ,rather than the other way around.
In this case, the o/p already has a yoke. He just needs to insert it, pull it back an inch, measure + to +, at ride height.
Done. (if it even clears the tunnel)
All those measurements are just going to confuse him more. We surely don't want that.
Plus they'd be hard to get , through the tunnel, with the old driveshaft still in there. ;-)

 

Every shaft I have ever had made they wanted it measured just like Mark Yac described. All the measurements are taken from center of the yolk U joint to the the center of the pinion U joint.

 

I had a beautiful aluminum driveshaft to use in my 40 coupe but it was 3” too short so I used the longer yoke from Speedway in my T-350. pushed all the way in and pull back out 1”. Works perfectly. No vibes.

 

Well I had one quote to have my shaft re-tubed/lengthened for $180, so that would the cheaper option. Although I am researching the tranny tail shaft swap to see if I am confident with doing that, as I have never done anything with transmissions before. I would just hate the fact of working backwards with removing the tranny I just put in. Also clearance isn't an issue. I am not understanding how 3" causes a clearance issue. Both transmissions are the same, so it would line up the same, just extended 3".