TBN retention

[Jetronic]

What if your car's manufacturer calls for a mid or (shock horror) low saps oil? Especially diesels with DPF run a risk of expensive repairs by not using the correct saps level.

But saps and TBN go hand in hand, so what can e done to preserve the oil's TBN as long as possible? I see long life oils with TBN below 5 (acea C4) even

My theroy is that by going higher in viscosity (read HTHS viscosity) you're less dependant on the AW properties of the zddp and can keep it for anti-oxidation use. Similar story with running cool (around or just above coolant temps) to reduce the need of anti-oxidants. Getting the engine up to temp regularly and letting dpf regens finish before shutting down are other things to keep in mind.

Anyone got other ideas? I notice a lot of customer cars where the oil is beyond spent by the time they come in for an oil change. I will never convince the owner to get another bulk tank with full saps oil since Castrol claims the magnatec we use (acea c3/A3/B4) is fit for all. I'm trying to convince the service manager to get some customers on severe service but he's not willing to sell that idea to the customers either. That's what got me thinking about my own car...

 

[Quattro Pete]

Originally Posted By: Jetronic
I notice a lot of customer cars where the oil is beyond spent by the time they come in for an oil change.

How do you determine that the oil is "beyond spent"? Just curious what methodology is being used.

 

[cat843]

Originally Posted By: Quattro Pete
Originally Posted By: Jetronic
I notice a lot of customer cars where the oil is beyond spent by the time they come in for an oil change.

How do you determine that the oil is "beyond spent"? Just curious what methodology is being used.


If its comes out like driveway sealer its spent. If none comes out, its spent.

 

[SR5]

Hi Jetronic,

I always though the sulphur content of the fuel had a lot to do with TBN retention, as it was the S in the fuel that contributed to acid formation in the oil.

Not too sure where you live, but in Australia, regular unleaded fuel has a maximum sulphur level of 150ppm, while high octane premium unleaded has a max S of 50ppm. One of the reasons I run premium fuel is for better TBN retention. I don't know if there is any differences with S levels in your fuels, but it may be something worth checking out.

Also that ACEA A3/B4/C3 spec., really annoys me, as it's not possible. Valvoline do it here, and it sounds like Castrol do it there. The two specs A3/B4 and C3 have a lot in common, like HTHS of 3.5 or more. But C3 needs a sulphated ash of 0.8 or less, while A3/B4 needs a sulphated ash between 1.0 and 1.6, so it not possible to be both. In Oz, Castrol is pretty good with this, and clearly mark two different Edge products 0W-40 A3/B4 for petrol and 0W-40 C3 for diesel.

TBN for A3/B4 is 10.0 or more
TBN for C3 is 6.0 or more.
I bet if you looked up the TBN of the Magnatec, it would be below 10, due to the sulphated ash levels required for C3.

What they should say is that it's a C3 oil, suitable for A3/B4 applications in areas with low sulphur fuel.

 

[Joe90_guy]

Here's my two pennethworth...

Yes sulphur will contribute to TBN depletion but most of the fuel sourced SOx you form in the combustion chamber will go down the tail pipe as gas. Most oil TBN will get depleted by carboxylic acids formed by the oxidation of base oils. The neutralisation happens in situ within the engine oil. Old fashioned Group I mineral base oils which contain a lot of easily attackable benzylic hydrogen eat through TBN very quickly.

Most Low SAPs oils rely on using high quality base oils, which are less easily oxidised to reduce the need for classic, over based detergent TBN. They also tend to contain a lot of antioxidant for the same reason.

You're quite right that C3 and A3/B4 are CURRENTLY mutually exclusive but if you go back in time, it wasn't always like this. There was a time when A3/B4 didn't carry a minimum TBN or minimum Sulphated Ash spec. If you were a clever formulator you could pass A3/B4 with low levels of additive which fell inside C3. One of the stranger things ACEA did was to arbitrarily increase the TBN min on A3/B4 to create 'distance' between Low and High SAP oils. How much this was due to pressure from certain parties to force the adoption of the newer oils, I guess we'll never know but it happened.

All I'm saying is that if you see a C3/A3/B4 oil, it maybe the A3/B4 claim is not current and dates back to an earlier incarnation of the spec. Remember you are under no obligation to quote the year of the spec on the can.

Speaking personally, I have always regarded Low SAP oils with deep suspicion. The concept originated in one particular additive company which just happened to have a sulphur-free detergent in its component slate. They saw a way this could be turned into a unique competitive advantage by playing on the fears on OEMs launching DPF equipped vehicles.

 

[zeng]

Originally Posted By: SR5
Hi Jetronic,

I always though the sulphur content of the fuel had a lot to do with TBN retention, as it was the S in the fuel that contributed to acid formation in the oil.

Not too sure where you live, but in Australia, regular unleaded fuel has a maximum sulphur level of 150ppm, while high octane premium unleaded has a max S of 50ppm. One of the reasons I run premium fuel is for better TBN retention. I don't know if there is any differences with S levels in your fuels, but it may be something worth checking out.


I regretted keeping a stash of C3 considering the low fuel quality of RON95/500 ppm S for the Japanese engines calling for SG and SM specs.

What's your comfortable OCI's with premium 50 ppm fuel , if you don't mind sharing ?

 

[zeng]

Originally Posted By: Joe90_guy
Here's my two pennethworth...

Yes sulphur will contribute to TBN depletion but most of the fuel sourced SOx you form in the combustion chamber will go down the tail pipe as gas. Most oil TBN will get depleted by carboxylic acids formed by the oxidation of base oils. The neutralisation happens in situ within the engine oil. Old fashioned Group I mineral base oils which contain a lot of easily attackable benzylic hydrogen eat through TBN very quickly.

Most Low SAPs oils rely on using high quality base oils, which are less easily oxidised to reduce the need for classic, over based detergent TBN. They also tend to contain a lot of antioxidant for the same reason.



I'm contemplating pushing Quartz Ineo Mc3 C3 OCI to 15K km, with 500 ppm S fuel here. In the absence of UOA ,is it excessive ?

 

[SR5]

Originally Posted By: zeng
Originally Posted By: SR5
Hi Jetronic,

I always though the sulphur content of the fuel had a lot to do with TBN retention, as it was the S in the fuel that contributed to acid formation in the oil.

Not too sure where you live, but in Australia, regular unleaded fuel has a maximum sulphur level of 150ppm, while high octane premium unleaded has a max S of 50ppm. One of the reasons I run premium fuel is for better TBN retention. I don't know if there is any differences with S levels in your fuels, but it may be something worth checking out.


I regretted keeping a stash of C3 considering the low fuel quality of RON95/500 ppm S for the Japanese engines calling for SG and SM specs.

What's your comfortable OCI's with premium 50 ppm fuel , if you don't mind sharing ?


Hi Zeng,

I'm not the best person to ask, as I don't do UOA (used oil analysis) like many of our American friends do, so I don't know how much TBN I have left in my oil.

My car calls for either a A3/B3 oil (TBN 8 or more) or a A3/B4 oil (TBN 10 or more).
It can run on either regular unleaded (S 150ppm or less) or premium unleaded (S of 50ppm or less).
The manufacturer suggest a OCI of 15,000 KM or 12 months (from memory).

If we assume I use the worst fuel allowed (150ppm) and the minimum oil allowed (TBN 8) then the manufacture still says this is good for 15,000 km (9.3k Mi). I also assume the manufacturer doesn't push it to the limit, and gives themselves a margin for error in their advice.

Now I can get mineral A3/B3 oils, but the better quality A3/B4 are either full synthetic or semi-synthetic. So with a full synthetic A3/B4 oil (TBN 10) and running the low sulphur (50ppm) fuel, I would consider 20,000KM (12.4k Mi) possible. Especially if this A3/B4 full synthetic was also MB 229.5 and BMW LL-01, which is often the case with full synthetic A3/B4 oils here.

 

[Joe90_guy]

It's a shame that Total don't actually say what the TBN of MC3 is (other than > 6 which is implicit for C3) but yes, I'd say you're okay for 15,000 km. Remember whilst the gasoline sulphur spec might be 500 ppm max the actual sulphur levels might be significantly lower. As I recall my oil industry days in Singapore, one if the defining things about Asia was that almost every crude oil has incredibly low levels if sulphur and this feeds through to all the refined petroleum products.

 

[SR5]

The Quartz Ineo MC3 5W30 is a good quality full synthetic oil. ACEA C3, API SN/ CF, MB 229.51, BMW LL-04, dexos-2.

It's a low SAPS oil with a TBN of 7.

To be honest, with 500ppm S in the fuel, I would change the oil every 10,000KM (6k Mi). Just to be on the safe side.

If you wanted to be adventurous maybe 12,000KM (7.5k Mi).

 

[SR5]

Originally Posted By: Joe90_guy
It's a shame that Total don't actually say what the TBN of MC3 is (other than > 6 which is implicit for C3) but yes, I'd say you're okay for 15,000 km. Remember whilst the gasoline sulphur spec might be 500 ppm max the actual sulphur levels might be significantly lower. As I recall my oil industry days in Singapore, one if the defining things about Asia was that almost every crude oil has incredibly low levels if sulphur and this feeds through to all the refined petroleum products.


Joe90 knows more about this stuff than I do, so I bow to his opinion.

BTW I found the Total INEO MC3 product data sheet, and they say a TBN of 7

http://www4.total.fr/nordic/auto_lubs/QUARTZ_INEO_MC3_5w30_ENG.pdf

It's from France, so I hope it's the same stuff.

 

[zeng]

Thanks heaps.

That embolden me to push for 15K km OCI.

According to my pdf file , TBN of MC3 5W40 registers at 7.5 :

CHARACTERISTICS*
Test Unit Test method Result
Viscosity grade - SAE J300 5W-40
Kinematic viscosity at 40°C mm2/s ASTM D445 83.9
Kinematic viscosity at 100°C mm2/s ASTM D445 13.9
Flashpoint °C ASTM D92 240
Viscosity Index - ASTM D2270 170
TBN mgKOH/g ASTM D2896 7.5


Btw, as of Jan 2015, Singapore's diesel and gasoline are both Euro IV 50 ppm S.

 

[SR5]

Zeng,
Ok 50ppm S in fuel, full synthetic oil with TBN of 7.5
Every post sounds better and better for 15,000 KM OCI.

Sounds like its all under control, and you have no worries.

Have Fun.

 

[supercity]

Originally Posted By: Joe90_guy

All I'm saying is that if you see a C3/A3/B4 oil, it maybe the A3/B4 claim is not current and dates back to an earlier incarnation of the spec. Remember you are under no obligation to quote the year of the spec on the can.

True, but the ACEA does not allow claiming of older specs anyway. An oil meeting C3/A3/B4 was only possible up to the 2008 version and that release can not technically be claimed after 2012. In practice that poses a lot of problems

Originally Posted By: Joe90_guy


Speaking personally, I have always regarded Low SAP oils with deep suspicion. The concept originated in one particular additive company which just happened to have a sulphur-free detergent in its component slate. They saw a way this could be turned into a unique competitive advantage by playing on the fears on OEMs launching DPF equipped vehicles.



I've always wondered why some DPFs can operate fine on A5/B5, Ford M2C-913 for example.

 

[zeng]

Originally Posted By: SR5
Zeng,
Ok 50ppm S in fuel, full synthetic oil with TBN of 7.5
Every post sounds better and better for 15,000 KM OCI.

Sounds like its all under control, and you have no worries.

Have Fun.



But I'm from Malaysia(not Singapore, sorry for the confusion), where RON 95 is 500 ppm at RM 2.00 per L.

I don't normally pump RON 97 of Euro IV 50 ppm at RM 2.45 per L into my Mitsubishi 1.5L carburreted and Daihatsu 1.3L Port Injection engines though.

Edit : I was referring to Joe90_guy's comment on Singapore earlier on.

 

[Joe90_guy]

I agree. ACEA don't allow use of old claims. However ACEA don't 'police' claims and the oil seller is completely self-certifing. I've been away from the industry for a few years now but back in the day, it was relatively common to see oil companies using theoretically redundant claims, especially in some of the second tier companies. I suspect if you looked hard, I'm sure you could go out today and find oils claiming A2/B2, even though this should have been ditched years ago!

On the Low SAP/DPF front, the thing to remember is that a Low SAP oil is not a No SAP oil! Phosphorus-wise, there's typically at most only 20% difference between Low SAP and ordinary PCMO. In the US, for Ilsac grades, there won't be any difference. Sulphur-wise, if you exclude Group I base oils, every other oil is essentially Low SAP because all other base oils are sulphur free. You get sulphur from ZDDP but this follows directly from the Phos limit. The common 0.3% max sulphur spec for Low SAP oil I always found objectionable because it forces you to use sulphur-free detergent. But here's the thing. If you upped that limit to say 0.33%, then the oil could quite happily accommodate normal sulphonate detergents. I always reckoned the 0.3% limit was a stitch-up! Then there's the Ash limit. I still find it hilarious that ACEA had to deliberately sabotage A3/B4 oil on ash to stop them legitimately being used in C3 applications!

 

[Jetronic]

Originally Posted By: Quattro Pete
Originally Posted By: Jetronic
I notice a lot of customer cars where the oil is beyond spent by the time they come in for an oil change.

How do you determine that the oil is "beyond spent"? Just curious what methodology is being used.


Varnish and carbon deposits, to the point that the dipstick is stuck solid in the tube...

 

[Jetronic]

Originally Posted By: cat843
Originally Posted By: Quattro Pete
Originally Posted By: Jetronic
I notice a lot of customer cars where the oil is beyond spent by the time they come in for an oil change.

How do you determine that the oil is "beyond spent"? Just curious what methodology is being used.


If its comes out like driveway sealer its spent. If none comes out, its spent.


diesles it comes out like water (even cold) unless they went even further. the thickening starts later on a diesel in my experience.

Petrols it's a goo coming out, or not coming out as the case may be. Varnish the colour of cherry wood.

 

[Jetronic]

Originally Posted By: Joe90_guy
I agree. ACEA don't allow use of old claims. However ACEA don't 'police' claims and the oil seller is completely self-certifing. I've been away from the industry for a few years now but back in the day, it was relatively common to see oil companies using theoretically redundant claims, especially in some of the second tier companies. I suspect if you looked hard, I'm sure you could go out today and find oils claiming A2/B2, even though this should have been ditched years ago!

On the Low SAP/DPF front, the thing to remember is that a Low SAP oil is not a No SAP oil! Phosphorus-wise, there's typically at most only 20% difference between Low SAP and ordinary PCMO. In the US, for Ilsac grades, there won't be any difference. Sulphur-wise, if you exclude Group I base oils, every other oil is essentially Low SAP because all other base oils are sulphur free. You get sulphur from ZDDP but this follows directly from the Phos limit. The common 0.3% max sulphur spec for Low SAP oil I always found objectionable because it forces you to use sulphur-free detergent. But here's the thing. If you upped that limit to say 0.33%, then the oil could quite happily accommodate normal sulphonate detergents. I always reckoned the 0.3% limit was a stitch-up! Then there's the Ash limit. I still find it hilarious that ACEA had to deliberately sabotage A3/B4 oil on ash to stop them legitimately being used in C3 applications!


When I worked for a peugeot dealer, we used total quartz 9000 5w-40 full spas oil in EVERY DPF equipped car, and we never had any DPF issues. that was until 2010 somewhere. Than I started working for a bus and coach company, and we retrofitted DPF's to some busses, but kept using the regular high SAPS Total Rubia TIR 8600 (iirc).

That was part of the reasoning I was looking at Total quartz 9000 Energy 0w30 oil, it's a higher SAPS than C3, but low according to A3/B4 standards, and TBN is 8.8. Combined with no oil consumptionin my engine I hoped it'd be a good choice until someone pointed me to the likely use of Shellvis...

So now I'm looking at Gulf Formula GMX 5w30, I'm done with the mid saps in my own application.

https://bobistheoilguy.com/forums/ubbthreads.php/topics/3860341/Gulf_formula_GMX_5w30

 

[buster]

Response from Mobil from a while ago.

Thanks for your message, Mike. We appreciate the feedback. A slight reduction in ash is desirable for advanced engine technology such as gasoline direct injection (GDI) engine and passenger car diesel engines. With GDI engines, higher levels of ash appear to result in a higher occurrence of Low Speed Pre-Ignition. The industry is currently developing tests and specifications to address Low Speed Pre-Ignition. In the future, passenger car engine oil specifications such as ILSAC GF-6 and dexos1 (next generation) are likely to have requirements such as lower ash to address Low Speed Pre-Ignition.

As for TBN retention, it is only a single parameter that provides an indication of the used oil condition. A reduction in TBN is an indication that the overbased detergent is doing its job by neutralizing acids that form as a result of combustion. TBN should be used in combination with other used oil parameters such as oxidation, nitration, TAN (Total Acid Number), ICP metals, D4684 MRV viscosity, and D445 kinematic viscosity to determine the overall condition of the used oil.

Finally, in our experience in severe-service Las Vegas field testing, Mobil 1 engine oil TBN levels typically do not drop below 2 for vehicles with 15,000 mile oil drain intervals. Furthermore, it is our experience that those oils tend not to drop any lower when we continue to 20,000 mile oil drains.

We hope this information was both helpful and informative. Thanks again for reaching out, and for your continued support of Mobil 1."