Bruze

Well this could go on forever, lol.

So you're joining the troll club also?

JasonAndrew

I was going to chime in and say, I don't typically drive my car in the cold, so the "0W" wouldn't have any benefit for me.

demon340

LDB

Assuming the VI improver is stable (a nontrivial assumption) 0W is better than 5W for all drivers, including ultra hot places like Las Vegas in the summer. All oil is too thick at startup. That’s why knowledgeable drivers take it easy until the engine is warmed up. 0W is less thick than 5W at all startup temps, so you thus get less startup wear with 0W. The only downside of 0W is that it requires more VI improver to make, and VI improvers have historically had shear stability issues. A 5W30 full synthetic can be made without using VI improvers, but 0W40 can’t.

On Demon340's quote, I could quibble and say that it pumps just as fast since oil pumps are positive displacement, but once it gets there, it's too thick. So for practical purposes, our points are the same.

dmk0210

So with the 0w synthetic, you're trading better lubrication at cold start for shorter oil change intervals then?

Or at least a shorter oil life if you are using it under "severe driving conditions" (to quote the manufacturer term)?

.

LDB

I know that conclusion was correct when I retired in 2010. It is possible that VI improvers are better (ie, more shear stable) now than they were then, but I’d be surprised if they were as stable as good quality base oil.

dmk0210

Thanks. It seems like a worthwhile tradeoff for my use.

FortMorganAl

This thread went off the rails at 04:37 PM on 02-23-2018.

But it has been an opportunity for a very good class taught by LDB. I learned something almost every day.

Bruze

joeking

This oil is meant for the C-7 and mostly if the car is driven very hard. The C-6's will last for many, many miles if you use the recommended oil. It doesn't have to be a specific brand. Now why don't you tell me what is the best kind of anti freeze to use? Just kidding.