Broken Diff
Bearings are all fine.
They were new when I assembled the spooled diff.
But you're right.
Something did move.
The bearing adjuster on one side (the part that screws into the cap and carrier) was blown out.The lock tab still had it in it's correct place but the bottom was blown out.
Whether this has caused things to move and the failure or whether the failure blew the adjuster out is hard to say.
Anyway,she's up and running again with posilok 3.55 489 centre.
It's booked in early new year to have the tranny pulled and disassembled.
My tranny mechanic was out there when I broke the diff and he doesn't feel I'd have hurt the tranny (it was built for the 493 stroker that's coming and is guaranteed to handle 800hp) but he said it'd be wise and good insurnce to check it.The box has done over 200 runs so he's interested to see inside it anyway.