T56 carnage from the dyno...what happened?
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T56 carnage from the dyno...what happened?
Alright story time
(Note all pics were taken as the parts were found without any modification. Also bigger pics can be found here!
http://home.comcast.net/~camaro2002s...Fun/index.html )
K, so I finally get the car together to a 'close to stock' state, and wanted to drive it around for the summer. Ultimately trading/selling it at some point next year. I had a friend put a stock tune on it so I could just get emissions out of the way and then tune for the heads, cam, and airlid at a later point to maximize what potential was still there.
So Friday the 2nd was the day to get it all tuned up . Got it strapped onto the dyno and hammered out the first run up to 6000ish rpms. Run went smooth. So 2nd run was going to be just another baseline pull as well. this time brought it up to about 6150/6200 rpms, disengaged the clutch, positioned the shifter into the neutral posistion, decel began, and then the fun started. Something made a quick BANG! and the whole car started to vibrate rather violently (If I were to ever go to a hotel with a vibrating bed I can imagine it would feel something like I felt), the shifter was bouncing all over the place, and there was some smoke that decided to show up as well. Took a quick glance underneath the car and saw the pool of fluid.
Pushed it off the rollers and found the tq arm just laying on the ground, along with tranny fluid, shifter boot cover, and some metal shards.
Then just had it towed. Obviously the end of the dyno session for me, lol. So I didn't get any tuning done, although my baseline pull was 358hp
Had some time to get a better look at the carnage yesturday. Here are my findings.
-The edelbroke (as Curtis put it, haha) TQ arm broke in two places by the rear diff
-I previously thought the drive shaft was bent, but it looks like it didn't bend/twist(probably was just the angle I had when looking at it previously). The front of the drive shaft is however completely seperated from the yolk. The drive shaft loop served its purpose . Note the Y-pipe hanger bracket and how it was bent down..crazy!
-Rear end appears to be okay as well, no noise when rotating the wheels. I'll probably pull the diff cover to take a look anyway (been needing to change the fluid as well).
-The shifter could be easily moved around without catching any gear, turns out that the bottom shifter ball was dislodged from the square thingy (sorry don't know what thats called, haha).
-Tail shaft housing of the transmission is cracked in 2 different places that I can see. The top portion near the shifter plate is nearly seperated from the rest of the transmission, and there's a large crack at the bottom.
-Not sure if there is any more damage waiting for me at the engine or not. Haven't started it up since the incedent.
I'm still not entirely sure what happened. Any insight would be great. There were three points of failure (that I know of)..which one went first?
Anyone have a stock T56 M6 tranny layin around they'd like to get rid of?
Brian
(Note all pics were taken as the parts were found without any modification. Also bigger pics can be found here!
http://home.comcast.net/~camaro2002s...Fun/index.html )
K, so I finally get the car together to a 'close to stock' state, and wanted to drive it around for the summer. Ultimately trading/selling it at some point next year. I had a friend put a stock tune on it so I could just get emissions out of the way and then tune for the heads, cam, and airlid at a later point to maximize what potential was still there.
So Friday the 2nd was the day to get it all tuned up . Got it strapped onto the dyno and hammered out the first run up to 6000ish rpms. Run went smooth. So 2nd run was going to be just another baseline pull as well. this time brought it up to about 6150/6200 rpms, disengaged the clutch, positioned the shifter into the neutral posistion, decel began, and then the fun started. Something made a quick BANG! and the whole car started to vibrate rather violently (If I were to ever go to a hotel with a vibrating bed I can imagine it would feel something like I felt), the shifter was bouncing all over the place, and there was some smoke that decided to show up as well. Took a quick glance underneath the car and saw the pool of fluid.
Pushed it off the rollers and found the tq arm just laying on the ground, along with tranny fluid, shifter boot cover, and some metal shards.
Then just had it towed. Obviously the end of the dyno session for me, lol. So I didn't get any tuning done, although my baseline pull was 358hp
Had some time to get a better look at the carnage yesturday. Here are my findings.
-The edelbroke (as Curtis put it, haha) TQ arm broke in two places by the rear diff
-I previously thought the drive shaft was bent, but it looks like it didn't bend/twist(probably was just the angle I had when looking at it previously). The front of the drive shaft is however completely seperated from the yolk. The drive shaft loop served its purpose . Note the Y-pipe hanger bracket and how it was bent down..crazy!
-Rear end appears to be okay as well, no noise when rotating the wheels. I'll probably pull the diff cover to take a look anyway (been needing to change the fluid as well).
-The shifter could be easily moved around without catching any gear, turns out that the bottom shifter ball was dislodged from the square thingy (sorry don't know what thats called, haha).
-Tail shaft housing of the transmission is cracked in 2 different places that I can see. The top portion near the shifter plate is nearly seperated from the rest of the transmission, and there's a large crack at the bottom.
-Not sure if there is any more damage waiting for me at the engine or not. Haven't started it up since the incedent.
I'm still not entirely sure what happened. Any insight would be great. There were three points of failure (that I know of)..which one went first?
Anyone have a stock T56 M6 tranny layin around they'd like to get rid of?
Brian
#4
Well, I can guess as what happened. The yoke broke first, driveshaft now is banging the sheetmetal up causing the weird vibration, the torque arm brakes from the driveshaft being loose and putting stress on the rearend. transmission starts leaking from the broken tailshaft causing the fluid to spill and burning on the exhaust.
#5
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I broke a torque arm at the track before.
Launching 5500 w/ a 2 step on slicks.Mine the torque arm broke & bound up the drivetrain on the launch. It broke the drive yoke for the pinion.It twisted the input yoke for the driveshaft also. The output shaft twisted as well & the VSS reluctor inside the trans exploded. All that & 2 universals, all was well again.
Went with a alston torque arm this go around, has been a great addition since.
Launching 5500 w/ a 2 step on slicks.Mine the torque arm broke & bound up the drivetrain on the launch. It broke the drive yoke for the pinion.It twisted the input yoke for the driveshaft also. The output shaft twisted as well & the VSS reluctor inside the trans exploded. All that & 2 universals, all was well again.
Went with a alston torque arm this go around, has been a great addition since.
#6
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Well, I can guess as what happened. The yoke broke first, driveshaft now is banging the sheetmetal up causing the weird vibration, the torque arm brakes from the driveshaft being loose and putting stress on the rearend. transmission starts leaking from the broken tailshaft causing the fluid to spill and burning on the exhaust.
Dayum, never seen that before.
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#10
We had something similar happen on my brothers Small Block S10 with a th350 though. We were doing some tuning and took it down the road to get some heat in the motor, stopped, took off hard, shifted into 2nd and BAM, clink clink, then lots of smoke. He didn't have a drive shaft loop, but nothing happened thank god because of the shaft. But we climbed under the truck and the tranny was laying in there crooked and all broken. Total carnage was split bellhousing (came out in 4 or 5 pieces), broken yoke, bent drive shaft, alone with some other things I'm sure, it was about 3 years ago.
But in your case are you sure that you didn't put it into 1st gear or something? I know its a stupid question, but it happens. I don't see how the TA would break from the yoke breaking since theres a loop. Did the tranny ever give you any issues before?
Sorry to hear about the tranny and car man, that deffinately sucks but your car looks badass from the pics
But in your case are you sure that you didn't put it into 1st gear or something? I know its a stupid question, but it happens. I don't see how the TA would break from the yoke breaking since theres a loop. Did the tranny ever give you any issues before?
Sorry to hear about the tranny and car man, that deffinately sucks but your car looks badass from the pics
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Guess it's pure speculation on how it actually happened, but thanks for the really good insight on what could have happened!!
I am positive the tranny was in neutral as the shifter was easily movable from side to side. I didn't even engage the clutch prior to all the action. I just put this tranny in a couple weeks ago and gave it some street time/experience to determine if there was anything wrong with it. Tranny felt good in my opinion.
I am positive the tranny was in neutral as the shifter was easily movable from side to side. I didn't even engage the clutch prior to all the action. I just put this tranny in a couple weeks ago and gave it some street time/experience to determine if there was anything wrong with it. Tranny felt good in my opinion.
#13
Guess it's pure speculation on how it actually happened, but thanks for the really good insight on what could have happened!!
I am positive the tranny was in neutral as the shifter was easily movable from side to side. I didn't even engage the clutch prior to all the action. I just put this tranny in a couple weeks ago and gave it some street time/experience to determine if there was anything wrong with it. Tranny felt good in my opinion.
I am positive the tranny was in neutral as the shifter was easily movable from side to side. I didn't even engage the clutch prior to all the action. I just put this tranny in a couple weeks ago and gave it some street time/experience to determine if there was anything wrong with it. Tranny felt good in my opinion.
Again sorry about the car man, what aare you planning on doing?
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yeah I don't think I would reccomend the edelbrock TA to anyone.
As of right now, I plan on pulling the tranny this weekend to see what more damage I might be lookin at. If there is no damage to the motor, I'll just fix/replace everything.
As of right now, I plan on pulling the tranny this weekend to see what more damage I might be lookin at. If there is no damage to the motor, I'll just fix/replace everything.
#15
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Well, I can guess as what happened. The yoke broke first, driveshaft now is banging the sheetmetal up causing the weird vibration, the torque arm brakes from the driveshaft being loose and putting stress on the rearend. transmission starts leaking from the broken tailshaft causing the fluid to spill and burning on the exhaust.
I dropped a driveshaft on mine and it gave the tunnel a good hammering.
Its likely it also hammered the end of the trans on yours.
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I'll put money on the torque arm causing all that. The torque arm was in a bind from not having pinion angle adjustments on top and bottom. Being strapped down to a dyno probably didn't help it out (straps pulling on the rear end straight back). the torque arm broke, which caused the rear end to shift backwards (way + pinion angle). That put stress on the u-joints, drive shaft, and tail shaft. Causing the cracked tail shaft housing and blown u-joints.