Viscosity Index Improvers are not bad.

[userfriendly]

A quick read on turbocharger deposits. There's a section which addresses VII (OCP vs Star). Might be worth reading if you're one who likes to run HDEO such as T6 in the hotter running turbo-gasser.

LINK

Duron 15w40 in my 2014 Ford Escape 2L turbo. There's no oil consumption between 4,000 mile oil changes, so in theory, the engine oil should have no impact on turbo deposits or emission system components.
I think that duty cycle has more to do with engine deposits than any other factor.

 

[BMWTurboDzl]

Duron 15w40 in my 2014 Ford Escape 2L turbo. There's no oil consumption between 4,000 mile oil changes, so in theory, the engine oil should have no impact on turbo deposits or emission system components.
I think that duty cycle has more to do with engine deposits than any other factor.

Your turbo shaft and bearings are lubricated/cooled with oil. This is the area of concern rather than oil deposits forming on the vanes themselves.

 

[wpod]

So my 8v-71 DD in my Ladder Truck will do fine on 5w40 CJ instead of SAE40 CF-2 ?

8V71s need to die.

 

[JohnnyG]

All good info from 7 years ago. Has anything changed since then?
Most issues I hear about today are (or seem to be) caused by oil cooking in the rings, sticking them, then causing oil usage and eventually cylinder wall damage. 20 years ago, I was told that was the result of poor VII's high temp performance.

The first post addressed cold temperature performance, and overall upper viscosity, but really doesn't address high temp performance in the ring areas of modern turbocharged engine.

Have there been any improvements in high temp PCMO performance? Is there one component or rating, or even BASE STOCK that can be used by the novice to determine which oil will resist stuck rings the best?
Since a lot of refiners make a PCMO that meets the various car manufacturers specifications, is that the only thing we should look for?

 

[userfriendly]

All good info from 7 years ago. Has anything changed since then?
Most issues I hear about today are (or seem to be) caused by oil cooking in the rings, sticking them, then causing oil usage and eventually cylinder wall damage. 20 years ago, I was told that was the result of poor VII's high temp performance.

The first post addressed cold temperature performance, and overall upper viscosity, but really doesn't address high temp performance in the ring areas of modern turbocharged engine.

Have there been any improvements in high temp PCMO performance? Is there one component or rating, or even BASE STOCK that can be used by the novice to determine which oil will resist stuck rings the best?
Since a lot of refiners make a PCMO that meets the various car manufacturers specifications, is that the only thing we should look for?

Well, after 19 1/2 years on BITOG, I'd like to know what you think.
Do you need a multi-grade in Daytona Beach?
Would using a viscosity that prevents oil consumption help prevent "oil cooking" in the rings?

Only your hairdresser knows for sure.

 

[JohnnyG]

Well, after 19 1/2 years on BITOG, I'd like to know what you think.
Do you need a multi-grade in Daytona Beach?
Would using a viscosity that prevents oil consumption help prevent "oil cooking" in the rings?

Only your hairdresser knows for sure.

20 years ago, Viscosity improvers were a problem. At least that's what I was told by a GM engineer. 7 years ago, I'm not so sure. See the recent post by OVERKILL on today's motor oil blends, it appears that base oils are the biggest problem for oil burning in the rings. Viscosity improvers are still used, but the amount depends more on the base stocks and not the oil grades. Plus there have been improvements in their high temperature performance.
Oil consumption can be caused by many different things. Even the amount of "crosshatch" on the cylinder walls. It's important that any oil that does end up in the rings (which is necessary for long engine life) that 1, can drain back out as needed, and 2, can withstand the ever increasing higher temperatures being present in that area.
Not my choice, but maybe a 0W-16 from new might be the best choice.
And, no, I don't need a multi grade oil in Daytona.

Further, I USED to think that the narrower the viscosity spread the fewer VII's are present. Which was mostly true 20 years ago. That no longer seems to be the case. It's more dependent on base stocks.

 

[userfriendly]

20 years ago, Viscosity improvers were a problem. At least that's what I was told by a GM engineer. 7 years ago, I'm not so sure. See the recent post by OVERKILL on today's motor oil blends, it appears that base oils are the biggest problem for oil burning in the rings. Viscosity improvers are still used, but the amount depends more on the base stocks and not the oil grades. Plus there have been improvements in their high temperature performance.
Oil consumption can be caused by many different things. Even the amount of "crosshatch" on the cylinder walls. It's important that any oil that does end up in the rings (which is necessary for long engine life) that 1, can drain back out as needed, and 2, can withstand the ever increasing higher temperatures being present in that area.
Not my choice, but maybe a 0W-16 from new might be the best choice.
And, no, I don't need a multi grade oil in Daytona.

Further, I USED to think that the narrower the viscosity spread the fewer VII's are present. Which was mostly true 20 years ago. That no longer seems to be the case. It's more dependent on base stocks.

What do you make of this?

Chevron Delo 400 SAE 10W
40C 45
100C 7.0

Havoline 0W16
40C 37.3
100C 7.2

Petro-Canada Synduro SHB 46
40C 47
100C 8.3
VI 151
PP -60C
FP 254C
oxidation stability 24 hrs @ 200C .4 TAN increase.

The first two are engine oils, the third is an industrial lubricant.