Smell oil or trans fluid burning

I already have and appointment to drop it off tomorrow so I'm set there. If I drive for any distance and stop for say and hour no issues with the truck at all, but if I drive someplace turn off truck and get back in with in about and hour and drive someplace when I get out I smell burning oil or trans fluid. It smells way stronger on the passenger side then the drivers side. I have crawled under and see no leaks and there is no drips on the ground either. I just drove it from CO to VT and it started a few days after arriving I had the maintenance done on it about a month before the drive so maybe 2500 miles on it since servicing Any ideas all wise ones

 

I am just repeating what @Jimmyh has been saying but grease is probably slinging off the u joints onto the exhaust. Did you have the u joints greased recently? I greased mine and sure enough I smell burning grease now just like Jimmy said would happen.

 

If they did it at servicing then yes. I haven't done it, but why would it only happen if I start the truck back up after sitting for a bit. That's the part that concerns me I'm just happy I have a work truck right now and don't have to drive it

 

Any leak point higher than the exhaust will be suspect.

Like valve covers, etc.

 

Thanks I have same issue and that makes sense