? about 1 of Pennzoil's responses about Ultra

[lonestar]

In the response from Pennzoil about Ultra there was a question about DI engines, specifically the GM 3.6L DI. The question pertained to the NOACK % of PU & potential impact on intake valves. Pennzoil’s response was as follows:

Oil volatility is not a significant factor for inlet valve deposits in a direct injection gasoline engine. The significant factor is viscosity modifier type and concentration, so using fully synthetic narrow span viscosity grades such as 5W-20 is beneficial. In North America, there is no specification calling for NOACK of less than 10%. The most important thing for DI engines is engine design, to better prevent deposits on ITV’s (In Take Valves), since there is no fuel wash as in PFI (Port Fuel Injection) engines.

Key statement, “The significant factor is viscosity modifier type and concentration, so using fully synthetic narrow span viscosity grades such as 5W-20 is beneficial.”

Naturally, the 3.6L DI calls for 5W30 however, based on Pennzoil’s response, are they saying a 10W30 would be better then a 0W or 5W30? If not, what are they saying?

 

[pbm]

I think they are saying that viscosity index improvers (VII) breaking down are the main cause of deposits. They are suggesting that synthetics use less VII than dinos and are a better choice in these engines.

 

[lonestar]

Originally Posted By: pbm
I think they are saying that viscosity index improvers (VII) breaking down are the main cause of deposits. They are suggesting that synthetics use less VII than dinos and are a better choice in these engines.


Assuming this is correct then one would want to use a synthetic with as low of VII # as possibel?

 

[brandini]

Yep

 

[Cup of Joe]

Like redline or Amsoil ACD which contains no VII.

http://www.amsoil.com/storefront/acd.aspx

http://www.redlineoil.com/product.aspx?pid=4&pcid=21

 

[mcrn]

So I guess this is a case where a better base stock is really important?

 

[brandini]

Yep, and really ANY Amsoil that specifically says 100% Synthetic will be good as well (if it's in your desired grade). It will just be a tad less good if it's a wider range. None of the XL oils qualify.

 

[Johnny]

No where in that answer from Shell did I read only Amsoil or Red Line oil will work, and especially the part that Amsoil XL oil do not qualify.

 

[DieselTech]

As I understand it, GF-5 and ultra would be great in a DI engine

 

[lonestar]

Originally Posted By: DieselTech
As I understand it, GF-5 and ultra would be great in a DI engine


Can you please eliberate?

 

[Cup of Joe]

Just to clarify I used the qualifying word "like" meaning similar too. Those are simply examples of no or low VII oils in the weight range provided above.

 

[DieselTech]

Originally Posted By: TaterandNoodles
Just to clarify I used the qualifying word "like" meaning similar too. Those are simply examples of no or low VII oils in the weight range provided above.


Some reading for you Lonestar. Most dont realize the Jump that will be taking place to DI and turbo charged engines in the near future
http://www.noln.net/inside_features/Future_motor_oil-X_0110.html?height=750&width=650

If this link is not allowed please delete

 

[mechtech2]

I also saw that statement from Pennzoil.
I do not believe it excludes volatility from the problem.
In other words, with oils that have no VII improvers, you will still get deposits from DI engines on the valves.

 

[brandini]

Originally Posted By: Johnny
No where in that answer from Shell did I read only Amsoil or Red Line oil will work, and especially the part that Amsoil XL oil do not qualify.


I was not exclusive in my statement. XL oils are Group II based and have much more group II in them than the oil they make labeled as 100% synthetic. That is a fact, and agrees with what the OP posted. Please reread what I actually wrote, not what you think I'm saying.

 

[DieselTech]

UHG, Amsoil XL is group III

 

[brandini]

[censored], that was a typo, I know they are group III, hence why i said they have more group II in them

 

[JAG]

This subject has been discussed before. Summary of factors identified in literature, including patents, that I've seen: base oil type(s), oil volatility, viscosity modifier type, viscosity modifier concentration, and presence of certain organic friction modifiers.