I have a 2012 Yukon xl slt and am currently in the black hills of SD. When driving up the long hill to get to the ski resort I notice a kind of rubber smell when we get to the top. I looked under the truck and saw no sign of anything rubbing on the tires. Is this the transmission getting too hot? How hot is too hot for the transmission, I can pull up the trans temp on my dash and it has not given me any warnings or anything. I don’t plan on driving back up the mountain only down when we leave on Saturday. Thanks