Anyone Break A Billet Output Shaft?

[Bowtie70SS]

Just curious what my $600 bought me. I really can't afford to rebuild this thing a 5th time. I did find a core with 50miles on it from a crash test vehicle as my last output shaft pretty much wiped out everything except the case and rear planetaries. What will I break next? Input drum/shaft? Which is best? Any other tips?

 

Dave

[misterp]

There are 3 output shafts -

 

1) stock - depending on the year of trans may or may not be heat treated, rated by Borg-Warner at 375 ft-lbs;

2) aftermarket hardened - this is what 90% of vendors sell as their "billet" shaft, it is really a stock GM/Borg-Warner shaft which has been further cryogenically hardened and rated at around 550 ft-lbs;

3) billet - shaft cut from a round 4340 billet on a CNC lathe, sent out for heat/cryo hardening, then finish-ground to final dimensions; I have only located these from Chris Kokonis (CK Performance) and when I asked him how strong they were he just told me "you won't break it" At $490 a bargain IMO but they are made to order so availability is always an issue. I'm getting one next week so we'll see from there how it does. I have it on reliable word that BenKey has been using Chris Kokonis' parts in his tranny, remember he has a 413...

 

Factoid - the output shaft on 2WD trucks has a better service record because it is a couple inches longer, so it twists more than the 4WD shaft without breaking.

 

CK also sells a reinforced input drum, and there is also a reinforced input drum called the Torque Drive (PATC); they are much improved but still you cannot have a bang shift with them or it just work-hardens the splines and it WILL fail in time (mine did).

 

Mr. P.

Edited September 21, 2007 by Mr. P. (see edit history)

[Bowtie70SS]

So what you are telling me is that the "Billet Shaft" that I bought from FLT is really a cryo'd stock shaft? If that is the case then I have a modern day case of the ass since I would have bought one from CK performance. Damn why do I always find out after I pull the trigger and buy something.

 

Dave

[Krambo]

So what you are telling me is that the "Billet Shaft" that I bought from FLT is really a cryo'd stock shaft? If that is the case then I have a modern day case of the ass since I would have bought one from CK performance. Damn why do I always find out after I pull the trigger and buy something.

 

Dave

 

Depends on what you ordered. Did you specify the "Billet 4x4 Output shaft" or the cryo'd output shaft that comes standart on the level V (last time I checked). There is a difference however, snapping a billet output shaft isn't out of the question but I would suspect that something else would give first.

Edited September 21, 2007 by Krambo (see edit history)

[zippy]

The billet shaft is very strong and shouldn't break. Breaking the stock 65E shaft which is hardened over a 60E shaft is impressive enough. You may want to look into having a bit of your line pressure dropped. It almost sounds like your trans shifts a bit too hard.

[Bowtie70SS]

I ordered a billet shaft...was like $580. My line pressure is at stock level or lower. I have Sonnax billet servos and a Zippy shift kit with a TBTC. The shift isn't that harsh...not to me. 1-2 is the hardest shift but the others are good and "firm". I have not raised the pressure manually via the set screw on the valve body. I guess we'll see pretty soon here.