In a fleet operation they switched from Mobil 1 5w-20 to Motorcraft 5w-20 for vehicles specd for 5w-20, with at least equal performance. The comparison might be a bit unfair to Mobil 1 because they were doing 5k changes. The lesson learned here, for us, is that the new breed of 5w-20 conventional oil is good stuff. The thing that triggered the testing and lead to the change was several increases in the price of Mobil 1. Motorcraft is a lot cheaper and under these conditions is working just as well as the expensive stuff. Several mechanics in the shop are now switching to Motorcraft, too. They are usually the last ones to come around to something new in engine oil.
