Had the Duster at the track and second pass after the burnout car slowed at the hit and rear end hopped, drive shaft will not turn in any gear.
verified its not the rear end, fluid is clear and good, no issues with linkage checked convertor bolts. Thoughts?
this is on a 12.80 340 car any help would be great
I am going to talk to the guy who just rebuilt it in the AM but just searching for clues
Thanks

Output shaft seized in the rear support. First thing popped into my mind. I don't know how bad a roller clutch or gear set would have to come apart to lock the whole thing up.

should also note that its got new sprag and billet front drum going to take it out this weekend

Guess I’d be dropping the pan to see if it hatched a porcupine egg. If you’ve seen a major trans failure and the ensuing mayhem stuck to the magnet, you’ll know what I’m talking about.

Yup, the pan will come off first. Question. is there anything that can come out of place and make this happen? No trans guy I am

CM’s scenario is a possibility..... I can’t think of anything off hand that isn’t the result of a major part failure. We’ll be waiting to see what is discovered.

Sounds to me like you may have been unlucky and lucky at the same time.

If the fluid's clean, it's not a friction element(s) welded itself together. Parking pawl is in the tail housing but never heard of one of them doing this. Anything failed to cause that will be in the back half/geartrain I would guess. If you start the engine and drop it in gear, does it act like it's in gear or does it free-rev?

Cocked servo piston holding it in two gears?

Every seized output shaft/support I've seen had cherry red clean fluid.

Not a 727, but I broke part of the converter snout off of a 904 way back. Happened at highway speed and locked up the driveshaft. Good times right there! I can't remember what the rebuiler said but I'm guessing it shot enough large bits through system when the broken piece made its way into the front pump to wedge fragments in throught the system. I do remember the fluid still seemed fine because it had no time to scorch and the bits were big enough to sink in the pan and not show up on the dipstick.

Maybe the parking pawl return spring broke?
More likely a broken rear sprag.

No "egg" pretty clear fluid, but not as clean as I would suspect
some fuzz on the magnet but not much

no change in rpm from gear to gear

Dropped the pan and fluid does have quite a bit of fine shiny stuff.
Took it in and wound up the sprag failed and chewed into the case,
clutches in the front drum some were coming apart.
So at this point not exactly sure what caused the failure but any ideas on that would help

Question when you did your burnouts where you starting out in first gear.

what kind of new sprag ?

Drive with a stock valve body, that may be the problem

A & A super sprag

I'd sure like to see a picture of this ORC failure.

Got one?