Maybe. Still, I have never seen a well designed engine have a oil related problem when properly maintained, and I have never seen a designer oil fix a known engine design problem.
What makes an engine require synthetic oil?
- Thread starter Chris142
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edyvw
$50 site donor 2025
The VW 1.8T debacle from late 90’s beginning of 2000’s is good example.
In Europe, VW required VW502.00 in 1.8T. That approval is synthetic oil.
In the US, to lower maintenance costs and be competitive with Toyota, Honda etc. they just stamped API SJ. Add to that small sump, and engines were sludgeing like crazy. Even with ILSAC synthetics they were probe to sludge. With VW502.00 they were OK.
In 2001 they changed recommendation to VW502.00, added larger oil filter to increase capacity.
But main culprit was that a lot of people just used cheap dino stuff.
Advantages are many: oxidation, shear stability, deposits, increased HTHS etc.
edyvw
$50 site donor 2025
Numerous well designed engines calculate in synthetic oils. So, proper maintenance has different meaning in different engines. Especially today when last mpg is being squeezed out with very high engine temperatures, turbos etc.
In that regard what 5W-30 in the US is not hydrocrack base oil and how can we recognize it?
M1 and Pennzoil uses gtl. Technically a group 3 but supposedly cleaner and perhaps slightly better?
So your saying said engines will do better with boutique oils on 10K OCI vs whatever oil at 5K OCI? I doubt it - assuming both meet whatever spec the OEM recommended. Should both be fine.
And if an OEM is under specing the oil or over specing the interval, then I would lump that under poorly designed engine, because if it supposedly designed to run on xw-xx and won't - that is in fact a design failure.
Thanks. So any other synthetics in Walmart particularly, incl. Castrol, Valvoline, Royal Purple are lower hydrocrack oils?
And in general how some people on here know which oil what group is since the manufacturers don't state that?
edyvw
$50 site donor 2025
You can see it in MSDS.
If they don’t list, there are other indicators like pour point (GTL and true synthetics have lower pour point. Low KV100 and high HTHS is another indicator (GTL is good here) as well as lower Noack.
Bad design or performance tuning that stress the oil beyond non synthetic.
edyvw
$50 site donor 2025
That doesn’t mean engine is bay designed. As I mentioned above, VW purposefully changed recommendations to be more in line with market. That is marketing decision, not engineering decision.
No, I wasn’t saying that. I was saying that there are excellent engines that require specific oils, but that doesn’t make them bad etc. Just bcs. something can run Supertech, doesn’t make it good engine.
He worked in the development of Motor Oils & Additives.
No, it doesn't make it a bad engine if it requires a higher spec oil, and that isn't what I said.
For example there are plenty of examples of your VW1.8T that did sludge even with higher end synthetic on short OCI. It wasn't purely people running dino oil for too long OCI - although running dino certainly did not help and made it worse, but it was just not a good design, which they "fixed" with a bigger sump and shorter OCI I believe. Were also talking about SJ spec which is light years behind anything your buying today - blend or full synthetic.
Most on here myself included get the sds sheets from the website to try to get base oil info. That's how we know about gtl and hydro cracked grp 3. Plus Pennzoil advertise gtl on the label.
Spot on brother
Why do you think the 10W40/30 would be better than a 5W40? The 10 vs 5 winter rating?
Which is also hydrocracked. And not "technically" a Group III product either, it fits squarely into the performance requirements for that base. It cannot fall into Groups IV or V since it does not meet the definitions.
Group III+ is sometimes thrown about by both blenders and manufacturers, but it only means that the base is on the upper end of the requirements. But other bases (non-GTL) also are on the high end. Without subsequent hydrocracking a GTL base stock does not meet the requirements for a Group III base.
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As noted, GTL is also hydrocracked. That is an important part of the synthesis to lower contaminates just as it is with a crude oil feed.
Remember that Group I-III designations aren't about method of manufacture but instead about performance. In fact they explicitly exclude manufacturing method and instead give performance requirements that could be met by any method. Groups IV and V are different.
Just as the finished product is defined by performance.
I thought GTL had to list Fischer Tropsch (spelling?) in the SDS?
Or is it acceptable to simply call it hydrocracked as well?
"Had to" is a bit harsh. Should the writer use the correct CAS registry number when preparing the SDS? Of course. Does that mean when a blender or manufacturer substitutes a different base stock under API Annex E they go back and change the SDS? No, not always if the substitution has the same toxicity, flammability and other hazardous properties. SDS are used for those purposes, not to provide Bitog members ammunition to assert that Pennzoil is better than Mobil 1 because it has their preferred base.
"Hydrocracked" is not a CAS registry number. It is a process. The use is a bit loose in SDS, sometimes they say it is hydroprocessed even when it is hydrocracked. SDS are also a means to obfuscate formulation as well, as long as it doesn't matter to the individuals that depend on the information for their safety and health. No formulator or blender will ever disclose a trade secret in an SDS.
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edyvw
$50 site donor 2025
1.8T was a very common engine in Europe at that time, and I was working at that time there in automotive industry. No issues with VW502.00 whatsoever. Here? Yes, it had issues with synthetic oils like Mobil1. However, I would not call it "high end" considering that with VW502.00 it did not have problems. I owned two Passats with that engine, one 1999, and one 20025. Never had oil issues. But then, I used appropriate oil.
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