What does it sound like when the rear diff goes?

[yat74]

I was getting ready to go on a great day of wheeling this past Sunday...When I started the rig up the service engine light and Stbilitrack failure light came on and the whole truck started to wobble or vibrate. As I drove around the block it seemed as if the RPM were running low and that some sort of binding (grinding) or lurching was present in the rear of the vehicle. I didn't take it offroad that sunday and started her up this morning and everything was normal. WTF...HELP...Going to the dealer this afternoon. The H3 is exactly 1 year old to this month and has about 18,500 miles on it. What does it sound like to you guys?