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RaptorSentry · 02-15-2015, 08:58 AM

I just got my engine rebuilt and my machinist said I should be running either 15w40 or 20w50, with an API of SL or earlier with ZDDP. So far the only street legal oils that that meet the above criteria I can find are the Royal Purple HPS 20w50 or Amsoil ZRod 20w50. Anybody know of any other street legal oils that meet the above criteria, and which one provides the best protection? As I want to keep this 350 running as long as possible.

02-15-2015, 08:58 AM	#1
RaptorSentry Registered User Join Date: Jan 2012 Location: Honolulu HI Posts: 36	Recommended Oil? I just got my engine rebuilt and my machinist said I should be running either 15w40 or 20w50, with an API of SL or earlier with ZDDP. So far the only street legal oils that that meet the above criteria I can find are the Royal Purple HPS 20w50 or Amsoil ZRod 20w50. Anybody know of any other street legal oils that meet the above criteria, and which one provides the best protection? As I want to keep this 350 running as long as possible.