Mobil Clean 5000 NOACK question..

[Mark72]

I was readinga used oil analysis forum on a different website and one of the members stated the following, and wanted to know what he means by this and if there is any truth to it? ---->

Just like synthetics, not all conventional oils are made the same and frankly some are better then others. Mobil Clean 5000 is an excellent conventional oil but, conventional oils, including Mobil Clean 5000 have too high of a NOACK % for the DI engine IMHO

 

[Stu_Rock]

Looking at the testing that PQIA did, it seems to have the second lowest NOACK weight loss of all of the major brand conventionals. The lowest was Exxon.

link: http://pqiamerica.com/testresults3a.html

I think one would need to go to synthetics to get much lower.

 

[shpankey]

Yes, for Direct Injected engines a low NOACK is very important to help with the valve buildup's common to them. Redline has a NOACK of 6 on I think all but their 0w oils. Some AMSOIL's have a 5.7 I think.

So while it may be low for a conventional oil, I'd go for a high end synthetic with a low NOACK on D.I. engines. Not only would I, I do, as I'm D.I. as well.

Maybe saaber will chime in, as he's really up on all of this and how it all relates.

 

[bepperb]

"for Direct Injected engines a low NOACK is very important to help with the valve buildup's common to them."

Works for me.

 

[Mark72]

So the conventional oils NOACK range from MC5000 12.8 and up the line through the other brands to 14. Is that really a big enough spread to say that MC5000 is the best on paper? Pennzoil Conventional is a great performer and it's NOACK is higher. Is there going to be a noticeable difference in 4k OCI between all the conventionals, or is it only going to make a difference when you get to where you are "really" extended the OCI beyond 5k?

 

[Nederlander75]

Keep in mind those NOAK numbers are for 5w30s. Some of the 10w30 mineral oils have NOAK numbers below 9%, Castrol GTX I think often scores down around 7.

 

[bepperb]

" is it only going to make a difference when you get to where you are "really" extended the OCI beyond 5k?"

No, the amount of vaporized oil won't vary due to age of the oil. Or, running an oil for 4000 miles, and a change and another 4000 miles would yield the same mass of vaporized oil as one 8000 mile OCI. If anything, the amount on the single OCI would be less as the more volatile compounds would vaporize earlier.

Lower NOACK should in theory give less buildup on the intake valves. There are a lot of other, perhaps more important variables. But I don't see OCI as being one of them.

 

[ottotheclown]

Many syn have similar Noack numbers too as the dino listed. Valvoline seems to have a low Noack of the regular priced oils. But like stated before GTX is also right in there with a low Noack number.