Here's a few pics:








Happened at around 100mph on the highway. I'm not sure if I was still on the gas or just let off when this happened. I was testing out my new 410s.

I'm trying to figure out the cause of death, but have run into a wall.

-Engine/tranny mounts were rubber and new.
-Driveshaft was balanced when I had it cut a while back and I've been running this trans and driveshaft for a long while.
-The rear had about 90 miles on it when this happened.
-I was able to find only 3 parts IN the trans that were definitely damaged: the stator (?) shaft on the front pump that holds the converter in place (broken in half), the rear (springs) bushing in front of the tail housing, and the sprag immediately in front of the bushing. The bushing and sprag are right behind the lo/reverse drum.

Anyone wanna guess as to how this baby died such an explosive death? Anywhere else I should look?

The tail housing completely exploded, so there was nothing left to investigate there. The front u-joint and yoke came apart from the driveshaft, but are not broken. A cap was missing from the u-joint.

The bellhousing was still bolted to the motor, but obviously the case broke.

 

I'd say the cap flew out of the yoke and the resulting
runout of the driveshaft caused the massive imballance
that wrecked the transmission(with 4:10s the
driveshaft had to be turning some rpm at 110 mph!)

 

But how did the input stator shaft break?

I just don't get it...

 

That got broken off by the broken transmission
thrashing around behind the converter.
BTW what did it sound like when this incident happened
and what did the car do?

 

don't know about you, but myself and all I've talked to who've also tried it agree that 700R-4s and 4.10:1s just don't mix. I love 4.10:1s with a built 200-4R, and while not a simple conversion, probably worth it.

 

I old have to say the driveshaft gave then the tail and bell broke then the shaft broke because it was trying to support it all , And i would say converter/trans and all are a total loss

 

Yeah converter, flexplate, and trans are dead.

The sound was like a ****ing bomb went off. All was well, and then BOOOOOOOM. The rear end locked up for a split second and then it was what you'd expect to hear, lots of grinding, breaking, and the awful noise of the driveshaft wanting to punch through the floor.

Thank god for driveshaft loops.

Wonder htf the cap fell off to begin with.

 

What brand converter is that? If it's a B&M(appears to be) it may have been part of the failure, otherwise I'd have to agree with what most others have said about the driveshaft/yoke/u-joint. - I'm not exactly understanding your discription of some of the parts that were hurt, but just from looking at the pics that is what I would guess to have happened.

Next time around, find a truck case. They're cast thicker, usually identifiable by a large "K" cast on either side the bellhousing, and/or the large convert cover bolt pattern made to accept 3 bolts on either side for the aluminum converter cover (not screws like the car case/tin cover).

As for gearing vs trans, that had nothing to do with it. The lower rear gears simply increased the shaft speeds and something either was already or became far enough out of balance to shake the living **** out of it.

On another note, if you ever see the results of an exploded reaction shell, you'll feel lucky in what you broke.