Have this EcoTec engine and thinking of switching to Pennzoil Platinum Synth Oil at 235,000 miles. Good shape (2006 yr). I have experienced immediate oil leaks with two Japanese cars ('92 and '97 vintage) in past after such a switch (but to different oils [Redline, Amsoil]).

Has anyone done this switch with Ford V6 and have knowledge good or bad? Please mention the oil brand if you recall. Thanks.

 

At this stage, I wouldn't make the change to synthetic.It could clean things up too well and could cause leaks. Your engine has made it to 235k miles. I would continue using whatever oil/ filter combination that has gotten your engine to 235k.

 

I agree, with those miles, and good results, why look for trouble.

 

Both, above - good practical comments. So oil/filter change last week was done as usual. Thanks for reality check.