I was a mechanic before all of the rainbow coolants were created. I am aware not to mix different coolants, and I knew there were issues with seals and such. I am just shocked this could be a result of just mixing coolants. I am not saying it is not the case here. I am just shocked!Mixing coolants and the resultant glop is unfortunately real. Don't know if stuff precipitates out of solution, but I do know it's a great way to mess up a cooling system. Does a number on radiators and heater cores as well as the cylinder head. Seem to recall printed warnings on jugs of antifreeze saying not to mix unlike types.

