Fully synthetic, Turbo life, and decent TBNs OIL

[Crankytank]

Van driving

I am at a point where I think its coming down to a choice between going to fully synthetic to protect my turbo for city ON/OFF driving, and an oil with a high TBN with the detergents that diesels need.

It seems the great majority of Fully synthetic oils, which are labelled diesel, have a low total base number like 7.0 and up, and perhaps are made for volkswagon euro small vehicles. How can these oils be labelled Diesel oil if they don't have the diesel detergent package which i think is indicated by a tbn of around 10 or up.

I have been using Valvoline Super diesel oil 15-40w (MINERAL oil) because I wanted to change oil at very short intervals and I didn't want to be throwing out a lot of good, expensive fully synthetic at short intervals. I look after my turbo but I want to look after it more and have piece of mind of having fully synthetic in that turbo now. I also want to look after my engine side of things and doesn't that require a good detergent package.
I had recently seen Mobile Delvac 1 which ticks all my boxes but seen nothing else similar. All the other full synth diesel oils have low TBNs.

Do really need full synth for the turbo or I just need to be careful to idle the vehicle for the turbo to cool down before switching off.

 

[Rand]

TBN is important .. TBN retention is more relevant.

You post is conflicted?

Extra high tbn is only good for extended drains, yet you post you are changing it frequently.

I'm not familiar with .au market oils.

In the US, Rotella T 5w40, delvac 1 5w40, m1 TurboDiesel Truck 5w40, Valvoline blue synthetic 5w40, Delo Syn 5w40, are all good products.

 

[Volv04Life]

I like this guy

 

[sicko]

Originally Posted By: Rand
In the US, Rotella T 5w40, delvac 1 5w40, m1 TurboDiesel Truck 5w40, Valvoline blue synthetic 5w40, Delo Syn 5w40, are all good products.



This. They have all shown to have very good OUAs. I like the Rotella T6 5w-40 which I've seen come back with many excellent UOAs, but all the oils Rand listed are quality oils to use.


Keep in mind that not all TBN is equal, it depends on the additive package used and other factors. Two different oils with the same starting TBN doesn't mean they can go the same distance. One might retain its TBN better than the other. If you're concerned, get a UOA w/TBN on your next oil change and see what the TBN retention was with your oil.

 

[dustyroads]

The delvac 1 would be a great choice if you want to run longer intervals. If you're going to run factory recommended intervals a conventional hdeo will be fine (unless the factory specifies something special).

I've never driven light or medium duty diesels, only heavy duty so I'm not sure what temps you would see in engine oil, transmission oil or exhaust temps. Maybe they're no different but I'm old school. I wait for all my temps to get stabilized before shutdown, which takes much longer in summer heat.

It may not be feasible for you to idle before you need to jump out and maybe not the least bit necessary. It depends on your situation. Even in my old school ways I only idle until I'm happy with the temps and in many cases that is just a couple minutes.

Many may tell you the turbo is water cooled and not to worry at all. In my experience, stopping the truck in hot weather means a temporary increase in transmission temp ( I guess from being hot from working and then a stop in air flow around it ). That heat combined with the heat soaked engine keeps the engine oil and exhaust temps from coming down right away.

I like to see my oil temp below 210° f and the exhaust temp below 350°f (preferrably closer to 300). That's just me. In cold weather it takes a blink of an eye but in summer it can take several minutes. The close knit packaging of modern engine bays keeps the heat in longer than the older trucks.

Your van may not need any idle time. The bottom line is you don't need synthetic hdeo for basic oci intervals.

 

[Crankytank]

Originally Posted By: dustyroads


Many may tell you the turbo is water cooled and not to worry at all.

Your van may not need any idle time. The bottom line is you don't need synthetic hdeo for basic oci intervals.


Isn't the idea that full synth oil is better for the turbo shaft, because, the turbo gets very hot and if shut off, when too hot, it can "cook" oil thats in there......and full synth oil doesn't cook nearly as easily as regular oil ? and cooked oil gets deposited in there causing problems like more heat in there ?

Also, why do you think these full synth diesel-labelled oils, in Australia, have such low TBNs.....possibly to cater for the euro diesel small vehicles, which run DPFs diesel particulate filters, which require LOW ASH formulas. I think low ash forumlas, are such, because of their low TBN total base number.

Anyone else think that mineral oil is fine for protecting turbos, in modern common-rail diesel engines. It would give me some peace of mind of I were to stick to this regular diesel oil. I was doing oil changes every 3000 miles with this basic mineral diesel oil.

Its hard to find, in Australia, a Fully synthetic oil labelled Diesel, which has a proper diesel detergent package (high TBN). They just don't have these things at the local auto stores. Even Mobile Delvac 1 is a hard to find item.

So its a matter of sticking the regular Super Diesel oil with a good detergent package, or going with a fully synthetic diesel oil with a low detergent additive package.
I also had some Castrol Tection HD at home which is mineral oil API CI-4 CI-4plus

 

[dustyroads]

Originally Posted By: Crankytank
Originally Posted By: dustyroads


Many may tell you the turbo is water cooled and not to worry at all.

Your van may not need any idle time. The bottom line is you don't need synthetic hdeo for basic oci intervals.


Isn't the idea that full synth oil is better for the turbo shaft, because, the turbo gets very hot and if shut off, when too hot, it can "cook" oil thats in there......and full synth oil doesn't cook nearly as easily as regular oil ? and cooked oil gets deposited in there causing problems like more heat in there ?


Yes, you have the right idea. I'm a proponent of getting it cooled down before shut off. I'm not the one who will say "don't worry...it's water cooled". However, if your turbo does have the benefit of coolant carrying some heat away it is a big help.

The bearing can suffer from oil coking which over time diminishes the bearing clearance and the cooling effect is lost. Eventually you have bearing failure (as you alluded to).

I'm just saying a conventional HDEO will work fine unless it is abused with an extreme work load and then immediately shut off. If that's the case then a synthetic would help but it still wouldn't be ideal.

As far as TBN; I don't know much about those lower detergent oils but there are some that meet volvo's VDS4 and Detroits 93k218 specs so they must be pretty good oils, even if the detergent levels look weak.

What kind of use are you talking about? I can guess that maybe it's typical pickup and delivery with many stops (?). If so, I think you're fine with conventional HDEO oil. Just use an oil that meets the engine manufacturers specs.

I hope the more educated weigh in here for you. Like I said in the earlier post I'm very careful myself before shutdown and I can relate to your concerns.

What kind/size/weight van are you driving? What engine? Just curious and wishing you well with it.

 

[dustyroads]

I just looked up the valvoline super diesel oil. I didn't look much at it as I need to get some sleep now, but the page I saw said it was only CH-4 rated. Is that what you have? If so, are there any concerns with emissions equipment?

If you can, try to at least upgrade to a CI-4+ oil. Sorry I'm not more aware of your offerings there in OZ. You did mention castrol tection earlier and that seems like it would be an improvement. Again, I don't know your engine and it's requirements.

 

[Crankytank]

just wondering would all the heavy duty diesels be running more full synthetic or more
mineral diesel oil?

 

[Crankytank]

Originally Posted By: dustyroads
I just looked up the valvoline super diesel oil. I didn't look much at it as I need to get some sleep now, but the page I saw said it was only CH-4 rated. Is that what you have? If so, are there any concerns with emissions equipment?

If you can, try to at least upgrade to a CI-4+ oil. Sorry I'm not more aware of your offerings there in OZ. You did mention castrol tection earlier and that seems like it would be an improvement. Again, I don't know your engine and it's requirements.


I've got no emissions equitment....no dpf etc. CH-4 not an issue. Thanks

 

[Shannow]

What are you driving ?

 

[dustyroads]

Originally Posted By: Crankytank
just wondering would all the heavy duty diesels be running more full synthetic or more
mineral diesel oil?


While I could only guess on the percentages, I feel very safe saying that the majority of heavy duty engines in north america run conventional hdeo. With so many synthetic blends available now, the percentages of use are probably changing and certainly some here run synthetic with aftermarket bypass filters.

I couldn't guess what is used more on other continents.

 

[A_Harman]

What is the Sulfur concentration in Australian pump diesel fuel? This would drive the TBN requirement of your oil choice.

No, you don't need a full synthetic oil to protect the turbo on your diesel. Diesel exhaust temperatures are hundreds of degrees cooler than petrol engine exhaust temperatures.

I run full synthetic in my diesel pickup, and I still allow a cooldown time before shutoff if I have been pulling hard.

 

[Doug Hillary]

Hi,
A_Harman - here in OZ our sulphur limit is 10ppm (since 2009)

Typical Pyro temps on an OTR diesel engine are;
Shutdown temp - 576
Warning - 420
Normal - 350

My Avg - 380
Low - 300
High - 425

I used Delvac 1 5W-40 over many millions of kms and many years. Expensive yes, but combined with a Mann-Hummel centrifuge and SS FF filter inserts my average OCI became 90k kms. The condemnation points were always Fe or Soot. Top up was 1 ltr 6k kms and the TBN factor was never an issue. My longest OCI was 130k kms

Sulphur levels were initially 500ppm moving down to 50ppm in this period

Most trucking fleets in OZ use either a mineral or semi-synthetic HDEO - typically 15W-40

 

[Charcoal]

what is the difference between Rotella T6, T5 and Triple T?
T6 is fully synthetic?
what abt the rest?
Thanks in advance.

 

[Clevy]

Originally Posted By: Charcoal
what is the difference between Rotella T6, T5 and Triple T?
T6 is fully synthetic?
what abt the rest?
Thanks in advance.


T5 is a semi syn and triple t is conventional.