Add me to the list of possible DexCool casualties. On 10/21/05 my 2000 Tundra with 106K miles was serviced with bulk DexCool by my local shop (only used Toyota Red before). At 139K the water pump was replaced due to a small leak during a timing belt change (I planned to change the pump anyway though). Immediately following the timing belt change, the radiator developed a leak and had to be replaced. At 143K, the thermostat housing developed a small leak through the seal. I replaced the entire manifold before the housing and the thermostat too. Coincidence? Maybe, but I took the truck to Toyota and had them hook up their flush machine and replaced the DexCool with Toyota Long Life Red on Friday. I'm hoping that I caught it before any more components start leaking. If I have a headgasket or intake manifold gasket start to fail now, I'm going to get very depressed.
Thank you BITOG'ers for alerting me to this DexCool incompatabilty issue!
BTW, the Red looks like it needs to be mixed with water. What kind of water is best to use? I have very hard tap water, BRITA filtered water pitcher (for drinking), and distilled water on hand.