I am about ready to change my ATF in my 2001 Ford F-350 Powerstroke Diesel. I have almost 90,000 miles and have been changing it every 30,000 miles. I have always been using Mobil 1 ATF but I have read a lot of good things about Specialty Formulations AutoGlide. My truck requires Mercon rated fluid. I know that the Specialty Formulations is a synthetic blend while the Mobil 1 is fully synthetic. Are there any advantages to swithing to the Specialty Formulations? I know that I would save a lot of money by switching.