Rotella or Delo 10w30 is all you need in SoCal. Stop the Lucas and CSL. May not have done any harm, but you don't need it. I like Delo gear lubes. SynGear 75w90 is excellent, the Delo ESI 80w90 is very good. Either would be fine, the syn MIGHT a little better if towing, but that being said, I've run the ESI 85w140 in my F350 for a very long time with zero issues. I tow a TT frequently. It just holds up well, and the borate formula is unique to them.
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