Well after several months, I am finally revisiting this since my back is now better and can get under the car to change the fluid. Now I just need to get the fluid. The Shell Rotella ELC red stuff that Mark mentions seems like good stuff. I have been using the Pestone orange stuff in the past with good luck though (photo). This would be for the red 5S with aluminum engine and radiator, so I am looking for something good with aluminum parts.
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