Turbo PCMO should only use HTO-06, syn etc. Myth?

[userfriendly]

Perhaps the best engine oil for a turbo application would not be friction modified or
fuel conserving, and contain very little or no VIIs.
Shopping for VI may be more wrong than right with turbos.
Would a high flash point instead of a high VI be the
answer for a turbo engine oil?

 

[Shannow]

used_oil...interesting points...

Have had little luck finding shaft journal (and bush) diameters for plain bearing turbos...If I can get those dimensions, I can calculate whether (and I suspect they are) operating in high shear, and "truth in viscosity" would probably make more sense that having a two plane viscosity at low and high shear rates.

The big diesel stationary engines 1000-1500hp use a light straight weight in the turbos (they have their own sump local to the turbo, and no forced oiling)

 

[Robster]

Hey Shannow. . .you have anything to do with the aviation biz (engineering) in Oz? I fly an Australian-made aircraft--nice ship!

 

[Shannow]

Robster,
nope, power stations, stuff that's tied firmly to the ground.

 

[userfriendly]

It can't be just my imagination that with two 6.6L Duramax engines, 2006 and 2011 the turbos
spool up quicker and the engines are more awake with SAE 30 than any other oil.

Clean coal technology, can it save the industry from natural gas conversion?
What is the domestic coal consumption for power generation in Australia?
In the USA I would guess around 2-3 million tons per day, and about
one tenth of that in Canada.
We are very lucky to have high volume fast flowing rivers that provide most of our power.

 

[Shannow]

Natural gas is being dumped in Oz at the present time, and the gas generators (even simple cycle GTs) are making hay...12 months ago, it was $4.60/GJ, now it's 50c in QLD, and $1.50 in my state...as the CSG and whatnot spool up in QLD in preparation for Oz' LNG export market.

Domestic prices are likely to hit $8-9/GJ within a couple years, and we are likely to have domestic gas shortages winter 2016/17...we will be exporting 4 times our total domestic gas consumption at that point.

I'm glad that some brave souls are initiating the nuclear discussion, as that's a conversation that my country seriously needs.

As to turbo's spooling...the brew that I'm running in my Nissan, I targetted a light 40, 3.5HTHS...and it does spool quicker (I can hear through the snorkel what the turbo's up to)...not sure whether that's HTHS or KV100 that's the culprit.

 

[userfriendly]

My problem is that I look at the oil pressure gauge too much, and end up
with an engine oil that is redundantly thick.
Using the oil pressure gauge alone to select a viscosity is a hard habit to break.

The 15W40s have been sneaking up in viscosity as drain intervals are extended year after year.
Now they play like a 15W50 with 4.4 HTHS and 15.5cSt @ 100C.
No wonder truckers are finding fuel savings with XW30s.
Perhaps the turbos like the lighter viscosity, if you look at the shaft speed.

 

[Robster]

@sds and @bluesubie. . . .I admittedly don't have any experience with the Subaru vehicles--I've never owned one, but some relatives and friends do and by all accounts are well-designed vehicles.

With respect to the Mitsubishi TD04--that turbo has MANY variants and has been around a long time, with literally millions in service worldwide. There's something to be said for that. . .it's used by many OEMs for a reason--it's reliability. A variant of the TD04 is used by Hyundai in their Sonata and Santa Fe and I've never heard of the turbo itself failing, although I've heard of wastegate controller issues.

I think much of the blame for turbo failure lies with the OEM and how they integrate the turbo and related hardware, i.e., how much boost are they asking it to make, is it adequately cooled, is it installed in a performance vehicle or a grocery-getter, etc.

As for oil requirements. . .although my Hyundai GDI-T is spec'd for dino 5w-30 oil, I know that the turbo thrashes / cooks the oil over the OCI and I use a syn 5w-30 that will deal with that operating environment (I hope) better than the dino. Will it?. . .if you believe the advertising claims, it will. Time will tell.

 

[wemay]

Time will tell Rob. So far so good. Hyundai/KIA have not changed the oil requirements on an engine platform (2.0T) that is now 5+ years old (some 2010's having been released in 2009). All while still providing a 100k mile powertrain warranty. I have not heard, and doubt they would jeopardize their reputation any further, after the mpg issue, by negating warranty claims for any oil related issue when most owners change oil at the dealership. Both of which, I frequent, continue to use conventional oil as bulk and many families purchased a maintenance package where this is the oil used in their SFS and Sonata 2.0T. These are normal, run of the mill folks who use their vehicles as daily drivers, idling in front of schools, getting groceries and driving work in rush hour. Maybe the short oci specified by the oem while under warranty, is what protects the turbo engine and warranty.

 

[buster]

While searching for GDI/deposit related issues I came across this old graph via Honda R&D. What Honda and XOM has found is that the TEOST test was inadequate at replicating a real world turbo charged environment for “used” oil. What is interesting about this simple Honda bar graph are how many oils failed it. Of course this was years ago. It’s definitely why extensive actual engine testing is so important. It’s also often why OEM specs can be above the common denominator basic API specs, in this case the TEOST.

I’m curious how Redline would do. Per Amsoil’s TEOST test results, RL didn’t even score below the max limit to pass the test. I’m not sure if it’s due to the moly they use or just that the TEOST is not an adequate measure of turbo charger deposit protection.

 

[1JZ_E46]

An LL-01/A40 approved oil would be better and far more modern than HTO-06 test. Thy both include turbo coking tests on actual turbo direct injected engines, not a test bench.