I had my 8-3/4 3.23 rear end blow up like that a few years ago.
I was merging into traffic doing about 70kmh going up to 80kmh (50mph)
When easing off the gas a loud clunking and bouncing from the rear end started. WTF??
So hazards on, pull of the road.
I assumed the drive shaft had popped off the differential but failed to disconnect from the tranny.
Nope, it's still still there.
So I fire her back up and slowly move it forward. clunks once every 8 feet or so.
Phone AMA and wait 2.5 hrs for them on the side of a 6 lane road...
After my mechanic pulled it apart, we found that 2 teeth from the ring gear had snapped off. One of them had become lodged in the ring gear and was being crushed by the pinion as it went around.
This is also when I discovered that the rear end was not a sure grip as I was told when I bought it, but a semi ceased diff that turned only under load
I found a used diff with 3.23 gears, had it all assembled and it held since.
So I separated the broken ring gear and pinion. One of these days, I'll turn it into a clock for the garage.
