I've been here long enough that I feel stupid for asking but here goes. Two weeks ago we traded the Grand Am on a 2003 Taurus wagon, 3.0L, calls for 5w-20. Looks like fresh oil and filter, I'm assuming that's what the Ford dealer where we bought it put in. OTOH, I'm a Mobil 1 guy. The 0w-20 M1 says it's okay to use in 5w-20 vehicles, but I'm hearing the siren song of the cheaper 5 qt jugs of 5w-30 M1 at Wally-World calling my name. On the third hand I'm not one to worry about saving $5.00, the 5w-20 so far does not come in 5 qt jugs. I will get a UOA at 20k, meaning the oil will have roughly 3800 miles on it (we bought the car with 16200), assuming it was changed then with Motorcraft 5w-20. Whaddaya all think? I don't mind paying for UOA's on all three and I will use a 5k OCI with a Motorcraft FL400S filter regardless. Thanks.