I have a 2005 Ford Thunderbird (3.9 L V8) with 18,000 miles. When I got it last year, my thought about the oil was "I'll get this schlock Ford Motorcraft oil out and put some great Mobil 1 or Amsoil in there once the engine's broken in." But I discovered this website and came to realize that Motorcraft is not schlock (plus I have free oil changes the first 25,000 miles). The car is used mostly on highways and will sit out most winters, so I figure semi-synthetic may be adequate protection for this kind of driving and maybe better corrosion protection than full synthetic. Also, I have to change the oil at least every 5000 miles for the first 100,000 on account of warranty issues, so figure that full synthetic may not be preferable for this reason as well.
This engine has also been used in a lot of Lincoln LS's and Jaguars, so I figure it has some kind of track record in terms of maintenance approaches and longevity. What I'd like to know is: can anyone give me a good reason to consider using another semi or full synthetic oil? I'm still thinking about Amsoil XL 5W20, Shaeffer 5W20, or Mobil 1. I'm using MC filters, but might consider the Amsoil Ea type, if it ever becomes available for this engine. Also, do semisynthetics provide a similar level of startup protection as full synthetics above 25 degrees Fahrenheit?
Thank you,
Cbird
This engine has also been used in a lot of Lincoln LS's and Jaguars, so I figure it has some kind of track record in terms of maintenance approaches and longevity. What I'd like to know is: can anyone give me a good reason to consider using another semi or full synthetic oil? I'm still thinking about Amsoil XL 5W20, Shaeffer 5W20, or Mobil 1. I'm using MC filters, but might consider the Amsoil Ea type, if it ever becomes available for this engine. Also, do semisynthetics provide a similar level of startup protection as full synthetics above 25 degrees Fahrenheit?
Thank you,
Cbird
