i twisted my output shaft but broke a ton of stuff inside before the output could break all the way. i know have a 4l60/65/70e flt lvl 7.

 

I broke 2, 4x4 output shafts. Both the same way and the only damage to the trans. These were GM, OEM, cryo treated shafts for 08 TBSS's (4l70e's i think). Snap!! Replaced the first with the second, then when It broke, I put a stock 2wd shaft in it and sold the tranny to a Fbody guy and runs 10's pulling the front wheels a it behind a NA 408.

 

from what i could see my output shaft looked like the back half of your lower shaft.

 

My LVL5 is at FLT right now because my 3-4 clutch pack wore out.Andy said everything else looked good inside.I've been running stock input and output shafts but I'm going to have them put a billet output in it while they have it.What is everyone's feelings on the input shafts?Do they need to be billet also?

 

yep she took a crap. No hardened parts, I spent so much to begin with I figured it should be fine with the power I was making I think its the input shaft because I still have park, I think now I can't remember Can a 4wd still have park if the output shaft broke??? I really need to pull it out and have a look. Is it common for the input shaft to break vs. the output.

 

i broke a stock and a hardened output shaft in my truck, went with a 80E and havent looked back

 

Mark, you see where both my output shafts are broke? I still had park AND reverse with them. I think the out put shafts break more then input shafts. Most of them break through the oil hole, like in the other pics in this thread. My first one, (the bottom one) was also cracked though the oil hole and you can see the twisting in the splines.

 

Update: Truck is back together but cyl #7 is dead. When the shaft broke the motor overrevved and killed the DOD lifter Time to start tearing it down and put in non-DOD lifters on both banks.....

 

update. Some info you guys might want to know...

When I pulled the 1900 off I found that the bottom part of each port on the spacers that go between the heads and the blower were blown out.

All eight of them. Not sure how fast this thing revved to but I did have my foot in it and the output shaft let go right at the shift about 6000rpms, so far more than that in a instant for sure.

Wonder how much boost it hit to cause the plastic spacers to burst

Cam, springs, pistons, lifter bore's all look good. Put in LS7 lifters and got the heads back on. Gotta wait and call magnacharger for a new set of spacers on Monday.

 

well hopfully if the ouputshaft broke and nothig else got damaged I might have a fairly cheap fix!! GOd I hope its cheap!!!