Sodium detergent and LSPI

[Jetronic]

According to LSJ Sodium detergent at any amount and Calcium detergent over about 1500 PPM is a big nono for LSPI. Since the oil I have and want to use in my coming ecotec LFV 1.5 tgdi has around 2000 ppm calcium detergent, I went and looked at dexos1g3 approved oils, and Ravenol has their DXG 5W-30 that I like. But i looked up an oil analysis and it contains calcium detergent at about 2000 PPM aswell, AND 400 PPM of sodium.

ZDDP and Moly are considered quenchers, but neiher are used in particularly high amounts.

The only thing I can, think of that would help such an oil pass any LSPI test is low Noack, and relatively high viscosity. Both would help reduce the presence of oil in the combustion chamber. Am I missing something though?

The oil I have has lower Noack, same-ish viscosity, about double moly and nearly 1000 ppm ZDDP, no sodium and the same calcium concentration. But it would never be tested for LSPI....

 

[92saturnsl2]

Lots of white papers and published articles out there demonstrating that sodium additives and hi CA levels promote LSPI. Are there other sources, probably, but I would be very leery of running these types of oils in a modern T-GDI engine.

Are you sure that analysis is current? It mentions Dexos1 (not the version), but also references API SN/SM. The switch away sodium/high CA additive packages took off when SN+ was introduced and subsequently API SP.

 

[Jetronic]

Lots of white papers and published articles out there demonstrating that sodium additives and hi CA levels promote LSPI. Are there other sources, probably, but I would be very leery of running these types of oils in a modern T-GDI engine.

Are you sure that analysis is current? It mentions Dexos1 (not the version), but also references API SN/SM. The switch away sodium/high CA additive packages took off when SN+ was introduced and subsequently API SP.

No I'm not sure it's current, but I'm not that familiar with Ravenol naming either. Could very well be an old formulation, though the viscosity and Noack track with Ravenol specs

 

[Titan]

It's more complicated than XXXX Calcium or YYYY Sodium is going to result in LSPI. As always, it's the combination of ALL the factors (including the oil chemistry as well as the actual engine design and current engine/fuel system condition) that determines if LSPI is a concern. I have a turbocharged small engine with Direct Injection that produces over 300 HP from 2 liters displacement, and I run an oil with calcium well above 2000. First, I checked with the manufacturer of this oil and they assured me it wouldn't be a problem due to all the other factors that contribute to LSPI or tend to quench it. I've run this oil the last 18,000 miles or so. Never had any indication of any problem...

 

[twX]

According to the studies I've seen, an oil with 2,000 ppm calcium will not pass an LSPI test even if the oil has a lot of ZDDP and moly. The maximum calcium for good LSPI performance seems to be around 1,600 ppm for higher-ZDDP oils, and 1,200 ppm for lower-ZDDP oils.

That said, the VOA you posted seems to be dated in 2016, and the oil is only certified API SN. If the oil now meets API SP and D1G3, it will have an updated formulation with less calcium and more magnesium, and should have passed both the API and GM LSPI tests.

The only thing I can, think of that would help such an oil pass any LSPI test is low Noack, and relatively high viscosity. Both would help reduce the presence of oil in the combustion chamber. Am I missing something though?

Noack is unrelated to LSPI. The oil that causes LSPI is in liquid droplet form. Viscosity also has poor correlation to LSPI.

 

[92saturnsl2]

It's more complicated than XXXX Calcium or YYYY Sodium is going to result in LSPI. As always, it's the combination of ALL the factors (including the oil chemistry as well as the actual engine design and current engine/fuel system condition) that determines if LSPI is a concern. I have a turbocharged small engine with Direct Injection that produces over 300 HP from 2 liters displacement, and I run an oil with calcium well above 2000. First, I checked with the manufacturer of this oil and they assured me it wouldn't be a problem due to all the other factors that contribute to LSPI or tend to quench it. I've run this oil the last 18,000 miles or so. Never had any indication of any problem...

You're a lot braver than I am. The LTG 2.0 had teething problems (cracked pistons) when it was introduced back in 2013? which GM attributed to both piston design (later revised) and oil formulation, specifically Na and Ca additives. This resulted in a newer Dexos1 spec. Their engineers are a lot smarter than I am, so I believe them. I do stray from Dexos1 oils as I like to use an Xw-40, but only when I'm certain it's SN+/SP rated which implies it's a low Na/Ca additive package.

 

[twX]

First, I checked with the manufacturer of this oil and they assured me it wouldn't be a problem due to all the other factors that contribute to LSPI or tend to quench it. I've run this oil the last 18,000 miles or so. Never had any indication of any problem...

Something to keep in mind is that LSPI frequency can increase a lot as the oil ages. This due to the suppressive effect of the ZDDP and moly additives diminishing as the they become depleted. High-calcium oils that rely on these additives can experience much more LSPI once the oil ages, even within a 6,000 km OCI.

A new LSPI test with aged oil is being introduced with ILSAC GF-7 next year, and I don't think any oils with 2,000+ ppm calcium will be able to pass this test.

 

[Titan]

Something to keep in mind is that LSPI frequency can increase a lot as the oil ages. This due to the suppressive effect of the ZDDP and moly additives diminishing as the they become depleted. High-calcium oils that rely on these additives can experience much more LSPI once the oil ages, even within a 6,000 km OCI.

A new LSPI test with aged oil is being introduced with ILSAC GF-7 next year, and I don't think any oils with 2,000+ ppm calcium will be able to pass this test.

Just a guess, or do you have actual lab knowledge you'd like to share? My last run was 10,000 miles.

 

[twX]

Just a guess, or do you have actual lab knowledge you'd like to share? My last run was 10,000 miles.

Mostly based on this paper by Lubrizol from 2018.

Here's a good article summarizing the issue.

"We think that molybdenum dithiocarbamate, titanium and zinc dialkyldithiophosphates may interrupt the LSPI precursors via their antioxidant properties,” Michlberger noted. “We also know that these additives decompose over time. As the additives decompose, they are no longer available to act to prevent LSPI.”

"Since the detergent rebalance removes the calcium, the bad actor, you are attacking the problem at the cause, not just treating the symptoms. We believe magnesium to be largely neutral—it’s really the removal of calcium that reduces LSPI propensity,” he explained."

LSPI events are rare and very random, but very damaging. Many engines won't show obvious signs that there's an issue until there's suddenly a hole in the piston. You can't really rely on your previous good experiences with an oil as an indication that it's doing a good job at reducing the risk of LSPI.

 

[BMWTurboDzl]

According to LSJ Sodium detergent at any amount and Calcium detergent over about 1500 PPM is a big nono for LSPI. Since the oil I have and want to use in my coming ecotec LFV 1.5 tgdi has around 2000 ppm calcium detergent, I went and looked at dexos1g3 approved oils, and Ravenol has their DXG 5W-30 that I like. But i looked up an oil analysis and it contains calcium detergent at about 2000 PPM aswell, AND 400 PPM of sodium.

ZDDP and Moly are considered quenchers, but neiher are used in particularly high amounts.

The only thing I can, think of that would help such an oil pass any LSPI test is low Noack, and relatively high viscosity. Both would help reduce the presence of oil in the combustion chamber. Am I missing something though?

The oil I have has lower Noack, same-ish viscosity, about double moly and nearly 1000 ppm ZDDP, no sodium and the same calcium concentration. But it would never be tested for LSPI....

The million dollar question is do you have an engine which is susceptible to LSPI? If so just look for something which meets the performance requirements of API SP or has Mercedes Benz 229.52 approval. Oils which are formulated to meet the performance requirements of API SP have a Mg/Ca ratio of something like .65:1

ACEA C6 oils meet the LSPI test API SP(SN+).

 

[SR5]

Is the sodium in the form of a detergent to add to the TBN?

That calcium level (as a detergent) may be sufficient for the TBN, at a rough guess. Maybe the sodium is in a different form that doesn't add to the LSPI.

Just an idea.

 

[MolaKule]

Is the sodium in the form of a detergent to add to the TBN?

That calcium level (as a detergent) may be sufficient for the TBN, at a rough guess. Maybe the sodium is in a different form that doesn't add to the LSPI.

Just an idea.

The soluble sodium alkyl aryl sulfonates are mainly used as rust preventatives.

Too high a level of the wrong calcium sulfonates is usually identified as the cause of LSPI.

 

[pbm]

I've been running older (SN) Valvoline synthetic (which was the high sodium version) in my GDI Focus for the past few OCIs (mainly to get rid of it). I've had no issues with LSPI but then again it's not a turbo. Has LSPI been an issue in non-turbo GDI engines?

 

[SR5]

I've been running older (SN) Valvoline synthetic (which was the high sodium version) in my GDI Focus for the past few OCIs (mainly to get rid of it). I've had no issues with LSPI but then again it's not a turbo. Has LSPI been an issue in non-turbo GDI engines?

My understanding was it is the Turbo Direct Injected engines that are the issue with LSPI.

 

[92saturnsl2]

My understanding was it is the Turbo Direct Injected engines that are the issue with LSPI.

You're not wrong, the higher combustion pressures in T-GDI is what really exposed this issue. That's not to say that it couldn't happen in a standard GDI engine; many are running 12-13:1+ compression and beyond.

 

[Titan]

You're not wrong, the higher combustion pressures in T-GDI is what really exposed this issue. That's not to say that it couldn't happen in a standard GDI engine; many are running 12-13:1+ compression and beyond.

It would be interesting to learn if this has been verified to occur in a non-boosted engine...I don't recall any reports of such. (Although "verified" is too strict of a word, the evidence is, at best, circumstantial...verification wouldn't technically be possible)

 

[gman2304]

I’ve been using Mobil1 EP 5w30 in the wife’s Ecotec 2.0T . I’m now wondering if the Valvoline RP might be a better choice as far as the slow piston and ring lands cleaning capabilities of this new oil and might it do a better job at preventing LSPI?

 

[BMWTurboDzl]

I’ve been using Mobil1 EP 5w30 in the wife’s Ecotec 2.0T . I’m now wondering if the Valvoline RP might be a better choice as far as the slow piston and ring lands cleaning capabilities of this new oil and might it do a better job at preventing LSPI?

Unless Ford recommends SN+ or SP you don't have to worry about LSPI.

 

[gman2304]

Unless Ford recommends SN+ or SP you don't have to worry about LSPI.

Her car is an early 2008 Pontiac Solstice with the early GM LNF 2.0T DI engine. You might have confused the GM Ecotec with the Ford Ecoboost?

 

[Insertcoolname]

i havent seen any sodium since valvoline max life.
they changed it again?