High mileage oil rabbit hole

[ironllama]

You know how you google something simple, like 'buick lucerne quaker state defy high mileage oil' and you start off reading one post about oil and gm6094m and how quaker staye defy is rated API SL which apparently means its for vehicles older than 2004 and it isnt on the gm6094m list of 'acceptable' oils but then you read a post saying that not all 'compatible' oils actually made that list and then you start to read up on oil engineering and you realize that maybe the oil you've been using isnt good for your engine and you start to worry and then u realize youve spent 30 mins looking at posts and you still havent answered that question:

Is Quaker State Defy High Mileage synthetic blend 'good' for my 2008 Buick Lucerne 3.8 that has 210,000km on it?
(Please answer...please)

 

[polarzak]

I cannot advise you on oil because I am one of those who think as long as it is a conventional detergent oil, and has the stamp of approval, ....oil is oil. As far as I am concerned, synthetic is a waste of money. That is just me, and no lecture intended.

My 06 was bought new and for the first oil change I did myself after the free dealer offer was over, and ever since, I have used Canadian Tire Formula 1, and a Canadian Tire oil filter. You can get a four litre jug on sale almost every week for about 15 bucks, five for an oil filter, which comes to around a $20 oil change. MY Lucerne 3.8 is pushing (maybe today) 300,000 km on the car, doesn't burn oil, and the engine purrs like the day I drove it off the dealers lot. My belief is that as long as we follow the manufactures viscosity recommendations, we need not to over think oil.

 

[ironllama]

So i checked the tech sheet for this oil and it says api sn compliant which is newer than sl.
So i just got in from changing the oil (made a mess on the road - dont change oil on a windy day) and thats that. Not gonna overthink it 😉