Was at Wally World yesterday and they had a fresh supply of Chevron Supreme 5w-30 on the shelves for $1.07/quart. I picked up enough for two changes in my wife's '96 Taurus. The Taurus has seen only two brands since we purchased it in '98.....Castrol GTX 5w-30 and Motorcraft 5w-30. The car is driven 80% local short trips (school bus stop, supermarket, gym, etc) and has had regular 3000 changes.
My plan is to change to the Supreme and drain after 1500 miles then change again and run 3000 miles and send a sample in for the Blackstone/Dyson analysis. I'll be using Supertech or Motorcraft filter(I already have one of each).
Mikep