Great Read Regarding Oil Choice!
 

Its long, save up some time and read this. Its internet gold.

http://www.bobistheoilguy.com/motor-oil-101/


Thanks to @ATL BRZ, @dsgerbc and @mav1178 for posting it. One of the most informative things I've read on the internet regarding oils.

I did a 24/25 on the test BTW :D


Edit: More great info on Bob is the Oil Guy forum regaring 0w-20 Oil, thanks to @bluesubie (who I consider Subject Matter Expert on Oils) and @dsgerbc)


More great info:

Thanks for that information, I will have to read through all of it at some point.

It seems like you struck internet gold! lol

Nick C.

@dsgerbc

Gotta give credit where it's due: http://www.ft86club.com/forums/showp...04&postcount=3

The link in that thread to 0w-20 oil talk on BITOG is also very useful, with lots of further links. Not sure it's worth linking that, but I thought I'd mention.

Share it, I'll add it to the OP. Thanks for the find.

http://www.ft86club.com/forums/showp...84&postcount=4

-alex

here, as posted here by @bluesubie
Pay more attention to posts by Shannow and Molakule.

The white papers written by Molakule in the Technical and White Papers forum are worth a read as well. "Tom NJ" also has a great write up on synthetics in that forum.

http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=postlist&Board=53&page=1

Those guys are experts. I'm just an oil geek. :D Occasionally at bitog you will see replies to threads by Doug Hillary. He has worked in Oz for many of the oil majors (Castrol, Mobil, Shell, etc.).

-Dennis

So let me try to understand what bob is trying to say.

0w-20 Synthetic oil is the better oil because it does not do as much damage on cold start as much as the other higher weight oils? And it really doesn't matter once it heats up because they all have the same pressure at normal-high operating temperature?
hmm... thank you Subaru/Toyota for making this car 0w-20. :)

That article gets linked on almost every thread in the mechanical maintenance section and no one bothers to read it. Definitely changes the way you think about maintaining your engine

For clarity, it wasn't written by "Bob" or anyone that works in the oil industry. It was written by Dr. Ali Haas, a plastic surgeon. ;) He does know a lot about oil though and an oil was named after him. (Renewable Lubricants Inc. 0W-30 Dr. Haas version, or something like that).

What he's trying to say is that most oils are too thick at start-up, but a 0W oil is usually thinner than say a 5W so it will flow more quickly at start-up.

I say usually because there are always exceptions. If you're talking start-up at 0C/32F, then there are 0W-'s thicker than 5W-'s and even 10W's thinner than 5W's. The first number is a representation of the apparent viscosity based on the results of the cold cranking test at -35C for 0W oils. Unfortunately, it does not tell you the viscosity above those temps.
http://www.pqiamerica.com/coldcrank.htm

But no, oils will not have the same oil pressure between different grades. Even within the same grade, a 0W-20 can have varying oil pressure based on the actual kinematic visocisty at 100C and High Temp High Shear. The second number on the bottle represents a range of viscosities but does not mean a specific viscosity.

A 20 grade oil (or 20 weight which people love to call it) can have a viscosity of anywhere from 5.60 cSt's to 9.29 cSt's. It's not correct to say that 0W-20 or 5W-30, for example, has a specific viscosity or thickness.
http://www.bobistheoilguy.com/viscosity-charts/
You have to find out the specific viscosity of the oil you're using by looking at the product data sheet for that oil. You can also do a virgin oil analysis.

HTHS viscosity affects oil pressure as well. You usually find HTHS on an oil manufacturers product data sheet. Here's a good write up on HTHS:
http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=1988816
Unfortunately, it's also written by an oil geek and not someone in the industry.

Oh wait, here's some HTHS info written by someone in the industry.
http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=530501&page=1

-Dennis

That was well worth the read :thumbsup:

Good read. I just follow the owner's manual recommendations for every car I've ever owned and I've never had a problem in 50+ years.

Me too, only 40 years. Many of my own oil changes also. I stopped when the environmental regulations added the need for a return trip to the hazmat depot. That added enough time and effort to the job I just take it to the shop now.

Driven many of these cars over 100,000 km and currently own two at well over 200,000 km with no oil related problems. No engine I have owned from new ever used significant amounts of oil, except the Alfa which is designed to use oil. Correct break in and correct oil changed at the specified intervals, not more or less frequently than specified, pretty much guarantees a trouble free engine for the life of the car nowadays.