I have a 92 DeVille with 142k+ miles. I have had very few problems with it and still seems to run fine, although since last winter I noticed gradual coolant loss. It was quite noticeable in winter and had to add good bit in the reservoir tank. It wasn't as bad as weather got warmer and in the summer it was barely noticeable. But come the fall with lower temperature the coolant starts to disappear again. There is no temp gauge in these cars so I can't even check for coolant temp. The coolant loss for now is very gradual; about half inch increment lower in the reservoir tank since topped off about 3 weeks ago (And I read the coolant levels in the morning after the car has been sat overnight). Is there anyone experiencing similar problem? Having lost another 92 DeVille to blown head gaskets a few years back, I'm really concerned. Any inputs would be appreciated.