Originally Posted By: bubbatime
You can run 5W20 or 5W30 as well with not a single issue at all. I would run Mobil 1 5W30 in your climate personally.
I bought my wife's 2010 Mustang GT 4.6 from a friend of mine who ran Mobil One 5W-20 the first 43,000 miles and changed it every 7,500 miles. The engine looked very clean w/o any varnish at all inside it. It did very well. I'm using Motorcraft 5W-20 in it now and changing it at 5,000 miles. You can use the other grade of Mobil One with complete confidence.
You can run 5W20 or 5W30 as well with not a single issue at all. I would run Mobil 1 5W30 in your climate personally.
I bought my wife's 2010 Mustang GT 4.6 from a friend of mine who ran Mobil One 5W-20 the first 43,000 miles and changed it every 7,500 miles. The engine looked very clean w/o any varnish at all inside it. It did very well. I'm using Motorcraft 5W-20 in it now and changing it at 5,000 miles. You can use the other grade of Mobil One with complete confidence.