GM authorizes Pennzoil Platinum as replacement

[tenderloin]

Polf I believe you are correct. Wasn't there was a recall of Coastal oil just a year or a couple years ago for not meeting specs?

 

[endeavor to persevere]

I posted this in the Valvoline thread. I meant to post it here. Recent list of GM approved oils:

http://gm.com/corporate/responsibility/environment/maintenance/gm_approved_engine_oils.pdf

 

[Boomer]

But we don't know what the internal allowed deviations are. In ISO documents, it would be all spelled out. And maybe this is measured in conjunction with another property with some combo of results being what is verified. We don't know enough to make any judgements on this at all.