Do you have snow where you live? If so, how do they treat the roads?

 

Yes I do. I live in Iowa. Treated with salt and whatever else they spray. The smell started on the way home after a trip up north camping where the roads were worse.

 

Sooooo... the reason I ask, is because I'm in Buffalo, NY. They use:
A splash of beet juice, a dollop of molasses, a squeeze of cheese brine. In the coldest weather, the recipe for safer roads often goes beyond the usual sprinkling of salt.
This makes for some strange odors for sure....ESPECIALLY after a long road trip where the exhaust is hot as hell.
Take the truck through a carwash with an under-belly wash and you should be good.

 

does the smell happen if you just let it sit and idle? that can help you rule out everything from the output bearing of the tranny to the brakes

 

So.....anything burning has a fairly distinctive difference in smell. Even the difference between burned power steering fluid and oil or even tranny fluid. Burning brake pads are VERY different than anything. Also is the origin from outside or inside the cab? What are the details of this smell so we can better help you?

 

It's probby from that skunk you ran over and you were too snaked up to remember!!