I need to shorten my driveshaft by a decent amount. My question is this. I am a decent welder. I'm not a professional, but I'm decent. At MIG and TIG on steel. I was thinking of shortening it myself and then just taking it to get rebalanced. My question is, how does the rear part of the driveshaft (where the weld is already) attach to the tube? Does it slide in or do the two just butt up against each other? I was plannig on trying to cut there so I dont have a weld in the middle of the shaft somewhere. Or am I thinking this is simpler than it is and should I just pay the $100 to get it shortened and rebalanced? I cant go farther on my exhaust till I get this done.

 

usually they slide in maybe a 1/2 inch and you weld the gap up but you have to make sure that the end yoke is almost perfectly round in it or you'll end up with a vibration and a wobble we had to spin it on a lathe and use a mic. to get it within .005

 

if you dont have the proper jigs and equipment, done do it your self. Probably end up wrecking it.

100 bux is not a bad deal to have it done right, but what is you current shaft? stock or aftermarket.

 

I was thinking I could make something fairly easily to hold it while welding. I also have a magnetic base dial indicator to measure runout. The driveshaft is a Spohn shaft. I may end up just waiting to get it done by a shop. After thinking about how much money I just spent, I'd hate to have the car drive like crap becuase the driveshaft isnt straight.

 

You can grind the weld off that you are asking about and the rear or front part will slide out. Grind the weld till you see the parting line, and the end should knock out. When you line it back up to weld back measure the end caps where u joint goes and get same measurement for each side. The weld should be the same all the way around, no clumps. That way it will balance better. Its pretty simple I have made dozens.

 

If you were welding up a driveshaft for a low speed rock crawler, doing a backyard weld is fine. For a street car, have it professionally done. A proper driveline shop will weld the driveshaft on a lathe or a roller table and if they're a good enough shop, they'll also balance it. They'll need the tranny slip yoke to balance the shaft.

I had mine custom built. New 1350 yokes and a 3" x .083" steel shaft. Cost somewhere around $300 many years ago but well worth it.

 

Alright, you guys talked me in to just waiting to get it done right. My shaft is the same specs as your Alky. Its chromoly too.