thinner is better

[zoomzoom]

so there is a quite a bit of the difference between 5W and 0W... 0W is 59% thinner to be exact!!

I wonder what would plot look like for those two viscosities from 0F to 212F in 10 F increments?

 

[zoomzoom]

Is thinner really better?

I will have my answer next week. Just drained M1 0W-20 form my 2000 Mazda 626 V6 after 6000 miles and sent sample to Blackstone for analysis. Engine is enjoying an Auto-RX wash right now

Previous oil in the engine was GC 0W-30. I'm dying to see how M1 0W-20 wear numbers will look against GC . This along with your valued opinions will give me idea what to run during the hot DC summer in my zoom zoom machine

 

[JohnBrowning]

First a well designed car should not lose prime? Second how much faster does a 0W30 reach the main bearing then a 5W30 or 5W40 at 80F or even 50F? Have you evwer pushed the handle on a hydralic jack and had any disernable delay in the movment?

Oil pumps are positive displacment. Last I checked 10W30 or even 15W40 is not that diffacult to pump at summer temps. Some of the people on this site make it sould like the oil pump is pumping frozen icecream up hill in Alaska through a straw!

The only way to reduce start up wear is to pre-pressurize the system! THis can be done with an accumulator or a elctrical oil pump.

If start up is the main cause of wear why doesn't the Toyota Prius have insane wear metal numbers?

 

[labman]

quote:

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Originally posted by JohnBrowning:
snip....

Oil pumps are positive displacment. Snip....

If start up is the main cause of wear why doesn't the Toyota Prius have insane wear metal numbers?

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Yes oil pumps deliver a constant volume, but part of it can go straight back to the pan when it is too thick.

As for the hybrids, the engine only shuts off after it is warmed up. It won't cool off very much through even the longest light cycles, nor will the oil drain down much.

 

[rob-the-oil-nut]

I for one would LOVE to see UOA on a hybrid where the gasoline engine is starting and stopping all the time. I'd also like to have an in-depth article on how those engines differ from normal engines. I've never even seen such a hybrid. I'm TOLD that you cannot hear or feel the engines shutting off or coming back on.

Can we come to a general consensus that the main difference between a 0W and a 5W is below 10 F? Or shall I pour over the whole thread some more?

BTW I did my part in asking RedLine to come out with a 0W30 for typical street use. I doubt they'll come out with it any time soon, but I still hope!