Yo Jan,
It must be ELC (extended life coolant); nothing else will do (maybe that Evans NPG+ stuff). I am not recommending Dex Cool as this is not the same thing. Here is a Shell web page pdf that explains better than I can. It is good for 300,000 miles or 6,000 hours before you need to add a booster; then it is good for another 300,000 or 6,000 more hours -- CRAZY. There is also no silicates in this stuff, so no green goo will crap up your tubes of the radiator. Anyway, judge for yourself on the following web page:
Shell Rotella ELC
Catch you later and GOOD LUCK!!!!
Mark
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