If it works for this application I will be shocked. That said, I have been shocked before seeing what JB Weld held up to.

The fluid in the transmission normally reaches 180 to 200 F, which means the case will reach at least that temp. Add to that the exhaust heat and vibration and there's very little chance that this will hold.

I guess it's worth a try, but I wouldn't be too hopeful.

Good luck,