Ls1Envy

iTrader: (6)

The other day my steel driveshaft let go on the dyno. I was there for tuning on my 2.73 car with a fresh H/C package. It let go on the 2nd pull@ about 6400rpms and around 400rwhp.

The driveshaft Completely separated from the Tailshaft housing and jammed up in the tunnel. The torque arm took a good hit also.

The car is at the Shop now and they said they could find another tailshaft housing and an Aluminium DS.

I'm just trying to figure out why it didn't let go on the 20 some passes and the 8 months of driving since I had it out. I never heard/felt any weird vibrations except for right before It went on the dyno, on a tight turn out of a parking lot onto the road. I recall it now, but just dismissed it as wheel hop or something at the time.

Do these high powered 2.73 cars have a history of steel driveshaft/tailshaft problems? It's odd that it would let go on the dyno and not on the street. The shop is waiting for the go ahead to fix it but I want to make sure that It isn't something else that I'm over looking.

skifast87

Well man i am afraid. Things break when they break. no one can say. Ok you have X amout of HP so your tranny is going to go in 1051 more miles. I would say after it was beat on for a while it just let go.

Ls1Envy

iTrader: (6)

I realize that. I'm just wondering if anyone has been in a similiar situation.

TheBlurLS1

iTrader: (8)

I wouldn't put a stock aluminum DS in it. Fix it RIGHT while you're at it. Use a 3" aftermarket steel, or a 3.5" aluminum.

The stock steelie shouldn't have broken with that power level and an auto, must have had some sort of flaw that didn't really show itself untill that day. **** happens.

I have this DS myself, barely heavier than a stock 3" Al, and it's plenty strong.

http://www.exoticperformanceplus.com....html?item=541

orangeapeel

iTrader: (18)

I have been standing next to a SS Silverado at the shop I used to work at when the magnacharged 6.0L spit out the aluminum DS and it bounced over a car on the lift next to it and damn near stuck in the wall. Steel all the way.

DANSBIRD

iTrader: (2)

I bet that would be scary as hell

TheBlurLS1

iTrader: (8)

G-Force had a little set of metal shelves next to their dyno at their old shop, and one of the shelves was beat/dented/bent all to hell. Mike said he was dyno'n an Avalanche and the driveshaft flew out the side and wrecked shop.

1fastz28nx

iTrader: (18)

Damn, that looks like a good investment since my DS is the weak link of my drivetrain now!

jam01

what is the torque rating on the shaft. i didnt see it listed.

TheBlurLS1

iTrader: (8)

Says tested to 1200hp, and unless it was used in a Poopra, it probably stood up to quite a bit of TQ too.

SMOKIN01TA has pulled a 1.38 60' on his 3.5" Al unit between some slicks and a 6-speed.

jam01

i was just curios. torque is what twists or breaks driveshafts. not hp, my other car needs an upgrade and they look like they are of good quality. they didnt give you spec sheet with #s.

TheBlurLS1

iTrader: (8)

Nope, no spec sheet. I can say that I couldnt ask for a more quality looking piece though.

Ls1Envy

iTrader: (6)

Whats the deal with posts I've seen about the steel driveshafts and location of the stock Torque Arm and the cracking of the tailshaft housings on these Autos. Anyone heard of this?

Ls1Envy

iTrader: (6)

I'll probably end up with a different tranny up there. Just got off the phone with the shop and they said 95% of the time the output shaft gets damaged when spitting a DS like that.