Looking for some coolant advice. My 14 Passat TDI is currently getting its engine replaced after clogging the heater core for the third time within a year. Dealer says VW is replacing every component that was in contact with coolant. The car has about 135000 miles, and is almost out of the emissions warranty. With that said my question to you all is, should I stop VW from install G13 and switch to a Heavy Duty Coolant like Rotella ELC? I plan on having the car tuned and deleted once all the bugs are worked out. I just want to make sure the coolant issue doesn’t start again. Thanks for any recommendations you have.