I have an 08 Mercury Mariner V6 with 198k miles. For 90% of the changes I've used Motorcraft 5w-20 blend and never a problem. In fact, I've used Motorcraft over 25 years in Sables, a Cougar, a Taurus and another Mariner.
This time, I'm thinking of Castrol Edge Extended or Valvoline synthetic. Would it be worth it?
This time, I'm thinking of Castrol Edge Extended or Valvoline synthetic. Would it be worth it?