I've used and recommended Dexcool for about seven years in six cars with only one hitch (below). But I think it's time to survey the accumulated wisdom and experience of the Board to find out how others have fared. Mullah Fuqua's latest travails with the Mother of All Volvos gives one pause for concern.

Here's my experience with Dexcool: six cars (two GM A-series belonging to the in-laws and four 740/940 cars based on B230F/T engines.) I completely flushed the cooling systems in each case, added Dexcool coolant, and then filled with distilled water. Because of various hose changes, radiators, etc. the average coolant lifetime is only about two years, so it gets changed regularly. It also stays at the "min" level in the reservoir: no low coolant levels. I have had NO corrosion or leaks in any of the six cars with one exception. I have had no water pump leaks, no cooling system deposits on the insides of the hoses or coolant reservoirs, and no rotten thermostats.

That exception was a new Nissens replacement radiator (OEM had plastic cracks). After one year on Dexcool, the solder started to dissolve and leak. High-lead solders are a weakness for Dexcool, it turns out, so I should have known. Went back to the Blackstone OEM aluminum-plastic sandwich with no problems. The same is true in the GM cars.

What's your experience? Any leaks or failures on Dexcool? Which component failed? If so, what practices did you follow (flush, distilled water, low coolant levels over time, etc.)? Lend us your wisdom.