Bought the truck with 100000. I have 217000 now. It had been "professionally flushed" to green coolant by previous owner. I have flushed it at least 3 times since I have had it now. So last week it started leaking coolant. It was coming from teh intake manifold gasket. Too cold to do it myself so I had my mechanic do it.

Fixed now, but he told me it happened because no matter how "professional" the first flush by the previous owner was, the old dex cool and new green react together and break down gaskets over tome. He said that the intake mani problem I had is always teh first sign. He also said teh head gasket usually follows suit within 10k after. Thoughts on this? Is he just freaking me out or is this a fact? I heard the coolants react badly together but the car has been over 10ok on green with no issues? Should I unload it while I can before the HG goes? Or should I not worry about what he said about the HG??? Help!!

 

I wouldn't worry about the head gasket. The "old" version of Dex-cool tended to turn to mud & clog everything up. With 217k miles, your not going to sell it for very much anyway.

I use the new universal prestone "green" anti-freeze that mixes with either type of coolant, dexcool or regular green.