THSCC Forums

Chuck, what you are describing is localized shear....and in my research is common among all multigrades oils or some straight weights (which do have a small amount of viscosity index improver polymers in some cases). The degree to which this happens is lesser in higher quality group IV/V PAO/POE oils (ie Euro oils ). I think higher HTHS is indicative of a lesser degree of localized shear for given circumstances.

Then there is permanent shear which is what we've been talking about and that's a whole other ballgame .

I'd be interested in reading/browsing that book you mentioned.

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2011/2012 Autox VP
2013/2014.5 President
2013 Top Gun

2015 Fit

22R-EC => 4G63 => D16Y7 + D16Y8 => EJ255 + K24Z2 => K20Z3 + K24Z2 => K24Z2 + M54 => L15B

Yep, exactly, I'm thinking about localized shear like in a rod bearing which was my impetus to study this book. Forget permanent shear for now -- it's hard enough trying to understand this crap as it is. Amazingly, there are still many areas that haven't been fully researched in this subject. I say amazingly since I feel like "after this long" just about everything you could think of should have been beat to death in an engine (specifically thinking about oil delivery to rod bearings, entrained air effects, cavitation problems, etc).

You're welcome to borrow the book James. It's 832 pages of light bedtime reading.
http://www.amazon.com/Engineering-Tribology-Third-Gwidon-Stachowiak/dp/0750678364/ref=sr_1_1?ie=UTF8&qid=1291251779&sr=8-1

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Current stable:
2019 BMW M2 Competition slicktop 6MT
2011 BMW M3 sedan slicktop 6MT
2007 BMW 328i wagon (slushbox for now)
1975 CanAm 125MX2

Thanks for the tip. I needed to do the 328i so I picked up 12.

The guy at the store wasn't pleased. He told me they get no credit for on-line purchases picked up at the store and next time to bring it in and he'd honor it. He was even less pleased when I showed him that they were $4.00 off. The receipt they printed out at the store showed full price, I had to show him the confirmation email on my iPhone before he'd believe it.

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Colin O'Connell

'94 BMW NASA SPEC 3
'02 F350 tow vehicle (not bad for a tow vehicle)
'97 Miata STO (autoX and sunny day spoils vehicle)
'97 BMW 328i (loaner to the kids when their cars don't work vehicle)
'05 Toyota Highlander

should have picked up 14 so you could do 2 full oil changes on your car or one on the 328 and one on the 325.

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#77 nasa spec 3
e36 M3

I just put in a second order, same store, same name, same CC. Went through fine... 30 min left

Back to putting shocks on the wrx....

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Mike Whitney
whit32@gmail.com, 919-454-5445
V10, V8, V8t, I6, I6, V6, F4t, I4, I4, I4, I4, I2, 1, 1

Thanks for the heads up, I got mine ordered. It is funny though that if you whisper oil in a room full of car nerds a fight would break out

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2002 MCS, 2003 MCS Track Rat, 2003 Generic White Yukon, 2003 BMWk1200rs, 1973 CB350F, 02 996. 08 Cayenne Turbo
http://www.clinehallagency.com

Thanks for the info. Picked up 12 quarts on way home today.

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Richard Casto
1972 Porsche 914
2013 Honda Fit Sport
2015 Honda Fit EX
http://motorsport.zyyz.com
Money can't buy happiness, but somehow it's more comfortable to cry in a Porsche than a Kia.