[bandit0067]

Thanks Bob B. So, if one had Mobil 1 bottled before around 2011 , it would prolly not be made to that specification , correct. But that was not something that affected LS engines made from 2000 to 2011. Wonder what was changed in the engine internals that needed the new specs or by years of analysis it was determined there was a problem.
Was heading out on long trip and did use older Mobil 1 for the trip. I shall go purchase the newer Dexos speced oil....thanks much