Thank you all for the info! Chris, I also take the same approach to cooling the engine before parking - but I wasn't sure if the problem was specific to me. It's been a while since this topic was brought up, but a mercedesshop search on redline water wetter doesn't really give a definitive answer. Does this stuff really work? - and is it safe for the cooling system components? It seems that if it does it would certainly alleviate this overheating problem if not solve it entirely. I trust the advice received here and if you guys give it the go-ahead I'll gladly order the product - I intend for this car to last me awhile yet!