Originally Posted By: demarpaint
I seriously doubt Ford would spec a 20 grade oil if they felt they would have problems. I'm sure they tested the engine, and are certain it will work properly on a 20 grade oil.
IMO, The car only has to last the expectant life consumers think it deserves. Gone are the days where we keep cars for more than 150,000 miles before we either expect to do repairs, it gets totalled, or we feel its just about worn out anyways, so we sell it, or toss it away and get a new one. If they (the car manufacturers) calculate that it can meet this expectation by cutting corners on various items, everyone perceives the process hasn't failed. Marketing is a powerful tool, the more credentials, qualifications (low maintenance, CAFE approved etc)you can put behind your product the better it is perceived.
My :2cents: