I am not sure if this post/issue is still open for comments etc.. I have a 2008 Dodge Sprinter,(Sprinter has 21,000 miles on it), Cargo version. Last week on a 2.5 hour night time trip home- windows open, outside temps were in the 90's- I was driving 75 mph for 1.5 hours straight when it started to feel, (or I just then noticed), like the heater was on. I felt around trying to locate the source of the heat and realized the seat bases were super hot. I pulled over and looked underneath and didn't see any glaring issues that could be causing the heat so I continued home. I drove around 60 mph the rest of the way- between that and going over a 1000 foot pass which then put me on the ocean side of the mountain where the ambient temp dropped into the low 70's the seat bases started to cool off. Yesterday I drove 20 miles- outside temp was 103 and the seat bases got hot again. I am not sure if this has always happened or it is something new. The Diesel Particulate Filer is right under the passenger seat and it gets hot as heck and the Transmission and Catalytic Converter are a little forward but might be part of the issue as well. All heat shields are in place and look to be in excellent shape. The next day I started vehicle and felt for exhaust leaks until I could no longer take the heat and I did not feel any leaks. I called the dealer and they said they have never heard of such a problem. Did anyone ever come up with an answer as to why this is happening? Is it normal? Thank you, Jim