I have always noticed a smell in our camper after traveling or when parked in driveway with the slides in. Today after setting up ladder to check roof I think I figured it out, it is the roof of the s...
I was just going to mention the sink traps. Since the smell appears after traveling, you may have shaken the water out of the sink traps on the road and the oders from your grey tank may be coming up through your sink.