I washed my X today, waited way too long again like usual. I always have the problem of tar on my X on the lower panels. I always just leave it on there as I didn't have anyway to get it off. I hadn't gotten and tried any bug and tar remover yet. As bad as the tar was I kind of think it might not have done that much. Well when I was washing it today I still hadn't gotten any but wanted to get the tar off so I can claybar and polish it soon. I sprayed it down first and got whatever loose stuff off. Scrubbed the lower panels with a brush. Ended up scratching a bunch of the tar off with my fingernails. So then I thought of trying the WD-40 to cut through the tar, and let me tell you it worked pretty well. I would spray it let it soak for a while, scrub off what I could and repeated a few times. It would desolve it enough that you could actually see tar streaks from where it was running off. I don't know what it would do to the paint and plastics. I kind of think that as long as it didn't have prolonged contact it would be ok. So after I did that I washed it. So now my X is a lot more tar free than it's been in years.