I don't have a stainless steel bottle (yet) so I can only offer a perspective from the original bottle. I try to keep mine about 1/3 full and I check mine when the car is warmed up. (easier to do with the original bottle) Obviously you don't want to open the bottle while the car is hot, so how to check with the stainless bottle is a good question. Generally, if my bottle is empty when the car is cold, I add coolant until it just starts to fill the bottle bottom, then warm the car up. I use prestone coolant in my system, but I mix it 50/50 with water myself before putting it in so I wouldn't have any qualms about using the premixed stuff. My 1992 Buick Century had a coolant leaking problem similar to what you describe. In the winter the car would leak after I drove it, but in the summer it never leaked. At the time I didn't have the $ to get the problem fixed so I just kept adding coolant. According to my mechanic the problem was indeed caused by the shrinkage of a seal. So it sounds very plausible to me. -Kevin VIN2234 ____________________________________________________________________________________ Sucker-punch spam with award-winning protection. Try the free Yahoo! Mail Beta. http://advision.webevents.yahoo.com/mailbeta/features_spam.html To address comments privately to the moderating team, please address: moderators@xxxxxxxxxxx For more info on the list, tech articles, cars for sale see www.dmcnews.com To search the archives or view files, log in at http://groups.yahoo.com/group/dmcnews Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/dmcnews/ <*> Your email settings: Individual Email | Traditional <*> To change settings online go to: http://groups.yahoo.com/group/dmcnews/join (Yahoo! ID required) <*> To change settings via email: mailto:dmcnews-digest@xxxxxxxxxxxxxxx mailto:dmcnews-fullfeatured@xxxxxxxxxxxxxxx <*> To unsubscribe from this group, send an email to: dmcnews-unsubscribe@xxxxxxxxxxxxxxx <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/