It might be easier to just get a new output shaft and get it cryogenically tempered. Actually you could get all the internals treated. I don't think it's very expensive.

Check out this site http://www.300below.com/deepcryogenics.htm

 

IllusionalTA

Your post suggests that you have actually converted your T56 to the larger spline output shaft. Did you have D&D do this or did you do it on your own? Has the upgrade to the larger shaft solved all of the T56 problems with broken output shaft and twisted splines in the yoke? Is there ary down side to this conversion like noise or vibration?

Thanks
Steve

 

That is a carbon copy of what I did to my 67 Camaro. I have a t56 just like you new boys. I am having a main/output shaft being made for me out of 4130 forged steel. If interested I will come back to you with a price for ya. I should have an update in about 2 weeks

Sean(Pig)

 

Sean,

Are you changing the spline size on your 4340 shaft? I saw the Powerglide boys use Vascomax or Vascalloy for their shafts. I'm sure that's just a trade name but it probably high Vanadium content. It might be worth looking in to.

Thanks
Steve

 

Steve, No I am not changing the spline size. A bigger diameter or more splines will not fit in a f body tail housing. The material that I am having this shaft made out of WILL hold! I also have the street twin.

Sean(Pig)