Pennz Ultra and consumption

[timeau]

Originally Posted By: CELICA_XX
I've been using the old PU 5w-30 for 20,000 miles and I still use a quart per 3,000 miles.

In this case there is a question: what did you get using PU? What was the profit? Just fashion and because of everybody uses it?
Very often I read here: "I drive hard, so I need synthetic". Wrong. Mineral oil serves you just fine, could be even better. If your car has "cold" thermostat (85-90 C) and you are not living in Alaska, you just throw your money.
"Hot" thermostat (controlled by wire, about 100 C) has just BMW, AFAIK. May be some other "Germans" too. They need synthetic because engine oil temperature on idle could be up to 120C.
Why on idle? Because "German" controlled by wire thermostat increased the engine temperature on idle for ecology purposes. But if you press on a pedal and drive hard thermostat is opened and engine gets colder. See a paradox? Hard driving - less temperature, better oil condition. Traffic with a lot of idle kills oil, whereas driving, even hard, increase it's life.
One more thing against using synthetic "just because". This picture shows the difference between obsolete mineral and fancy synthetic. Pay attention what is inside of spoon. Same thing you have on your oil rings. And many-many synthetic oils are affected, especially Shell (Mobil1 is better, I mean safer).

Shell (i.e. Pennzoil) Ultra:

Mobil1:

 

[CELICA_XX]

Originally Posted By: timeau
if you press on a pedal and drive hard thermostat is opened and engine gets colder.

See a paradox? Hard driving - less temperature


You sound like you really know what you're talking about.

 

[timeau]

Not in your Celica: this was told about wired thermostat in BMW N-series engines.

 

[HangFire]

Originally Posted By: timeau
Pay attention what is inside of spoon. Same thing you have on your oil rings.


I would expect a 5w-40 SN to have high volatility than a 15w-40 SG. The pictures don't scare me off of US market synthetics. For one thing I question the true temperature control of the spoon apparatus.

The ASTM D5800 NOACK numbers of most all US market synthetic oils are published, the rest are available on the PQI website. Same with the ASTM D445 100C cSt. In turbos is where synthetics really shine by their ability to avoid coking. SOPUS's (Shell's) PU in particular passed industry standard tests and had the least residue on pistons and rings.

Yes for many non-turbo applications, synthetic is overkill, but it's hardly dangerous, at least good quality US Market synthetics like Shell/Pennzoil and M1.