I think I had this at Hello during the show yesterday:
A broken motor mount causes the “KurClunk!” when it downshifts. The mount may have broken because it’s a Jeep and the owner mentioned actually driving on rough roads occasionally – or maybe it’s broken just because it’s a jeep! But to be fair, my Honda CRV also had a similar KurClunk which I thought would be trans, but turned out to be motor mount. Take the broken mount plus KurClunk, and eventually the exhaust gets a crack between the manifold and catalyic converter. She’s slow enf in the parking lot that she smells the sulfer. How bout them apples? I hope she isn’t also getting CO inside the car at all speeds.