I have tested a lot of different API SP oils from the Walmart shelf and came to the conclusion that any API SP oil will have excellent iron wear results. Much better iron wear results then what I saw in API SN and API SN+ oils. However, the constant issue seemed to be fuel dilution and how will that effect the detergents in the oil to prevent high mileage sludge.
So I have picked Quaker State Euro 5W40 API SP as the oil for my Ecoboost engine. Its 20% thicker than typical 5W30s and contains a lot more detergent than typical 5W30 oils. When I look at this oil I feel like its a heavier duty oil then your typical 5W30.
One thing I was reading on the Castrol website was that motor oil was never designed for gasoline as an additive to the oil. However, these Euro style oils are designed for the turbo engines which have been used for a long time in Europe. So while your typical Pennzoil or Mobil 1 5W30 was not designed for gasoline as an additive this Euro oil was actually designed with fuel dilution (gas in the oil) in mind.
So I have picked Quaker State Euro 5W40 API SP as the oil for my Ecoboost engine. Its 20% thicker than typical 5W30s and contains a lot more detergent than typical 5W30 oils. When I look at this oil I feel like its a heavier duty oil then your typical 5W30.
One thing I was reading on the Castrol website was that motor oil was never designed for gasoline as an additive to the oil. However, these Euro style oils are designed for the turbo engines which have been used for a long time in Europe. So while your typical Pennzoil or Mobil 1 5W30 was not designed for gasoline as an additive this Euro oil was actually designed with fuel dilution (gas in the oil) in mind.