How is HTHS measured?

[edyvw]

I thought there'd be a standard but looking at Molygen 5w40 vs 5w50 I was perplexed. The 5w40 seems pretty light and says a HTHS of 3.5 which barely makes BMW LL01 spec but then the 5w50 shows 3.7 which seems super light. Redline 5w30 is 3.7. QS Euro 5w30 is 3.88. So how can they call an oil a 5w50 if it's a HTHS of 3.7? Is there a standardization I'm missing?

They are giving you a minimum HTHS.
It is LM their HTHS will be mediocre to average for that grade.

 

[FlyingTexan]

They are giving you a minimum HTHS.
It is LM their HTHS will be mediocre to average for that grade.

Yea I figured but thought there was some industry standard. Seems almost like they can call their oil whatever they want.

 

[OVERKILL]

Yea I figured but thought there was some industry standard. Seems almost like they can call their oil whatever they want.

Just the minimums as noted in J300, grade is otherwise predicated on KV100.

 

[FCD]

Most 5w50s are in the 4.2-4.4 ish range.
With a thicker base oil like 15w50 or 20w50 you can fairly easily get over 5.0 without the need of too much VII

 

[BMWTurboDzl]

I thought there'd be a standard but looking at Molygen 5w40 vs 5w50 I was perplexed. The 5w40 seems pretty light and says a HTHS of 3.5 which barely makes BMW LL01 spec but then the 5w50 shows 3.7 which seems super light. Redline 5w30 is 3.7. QS Euro 5w30 is 3.88. So how can they call an oil a 5w50 if it's a HTHS of 3.7? Is there a standardization I'm missing?

When it comes to LM they list the minimum* allowed rather than actual HTHS. The min HTHS for 0/5/10w- 40 grade is 3.5cP and for a 50 grade it's 3.7cP. For example with your 5w40 Molygen LM states "hths >\= 3.5cP".

*As dictated by grade or approvals.

 

[YZJB]

RS recommended 5W50? Interesting.

5W-50 in Focus RS only for USA. Factory fill is 0W-40 A3/B4 and all markets except USA specify 0W-40 for service fill.

 

[YZJB]

Interestingly SAE 40 has two different HTHS limits. For SAE 0W-40, 5W-40 and 10W-40, the HTHS limit is 3.5, whereas the limit is 3.7 for SAE 40, 15W-40, 20W-40 and 25W-40.

https://www.stle.org/files/TLTArchives/2023/04_April/Lubrication_Fundamentals.aspx

Minimums, not limits.

 

[Patman]

5W-50 in Focus RS only for USA. Factory fill is 0W-40 A3/B4 and all markets except USA specify 0W-40 for service fill.

That’s interesting and I had no idea. It’s the opposite of what often happens where the US gets the thinner oil.

 

[YZJB]

That’s interesting and I had no idea. It’s the opposite of what often happens where the US gets the thinner oil.

Motorcraft doesn’t make a 5W-40 or 0W-40 A3/B4 oil, so the 5W-50 was chosen as the closest fit. Ford has a requirement in the USA that the service-fill oil must be able to be supplied by Motorcraft. That doesn’t exist outside of USA; Ford usually recommends Castrol in other markets.

The factory fully for Focus RS was Castrol Edge Professional A3 0W-40, Ford WSS-M2C937-A.

 

[fantastic]

Minimums, not limits.

The information makes it all that more important to know the minimums if you're needing a higher HT/HS. If a 5w-40 is generally going to be around 3.5 minimum then you know if you go straight to a 15w-40 it will give you a bump in HT/HS minimum of 3.7. I'm sure they're oil makers that do it towards the minimum requirements & not the maximum.

 

[OVERKILL]

Which makes it all that more important to know the minimums if you're needing a higher HT/HS. If a 5w-40 is generally going to be around 3.5 minimum then you know if you go straight to a 15w-40 it will give you a bump in HT/HS minimum of 3.7. I'm sure they're oil makers that do it towards the minimum requirements & not the maximum.

The Euro oils, which are geared around approvals with an HTHS floor of 3.5cP tend to, not surprisingly, be around that range of 3.5-3.8cP. On the other hand, many of the HDEO's are considerably higher, even in the same grade.

Example:
Mobil Delvac 1 ESP 0W-40:
HTHS: 4.1cP

 

[edyvw]

The information makes it all that more important to know the minimums if you're needing a higher HT/HS. If a 5w-40 is generally going to be around 3.5 minimum then you know if you go straight to a 15w-40 it will give you a bump in HT/HS minimum of 3.7. I'm sure they're oil makers that do it towards the minimum requirements & not the maximum.

5W40 in general is 3.6 (mediocre stuff) to 3.9/4.0.

 

[fantastic]

5W40 in general is 3.6 (mediocre stuff) to 3.9/4.0.

But if HT/HS is not known it's nice to know the minimums & options of other grade variants that have a higher minimum requirements. Take a 5w-40 with no mention of it or a 15w-40 with no mention of HT/HS. You now know the 15w-40 might very well have a higher HT/HS. Still not guarantees but good to know. Like you mentioned 3.6 is just a spec above the minimum.

 

[fantastic]

The Euro oils, which are geared around approvals with an HTHS floor of 3.5cP tend to, not surprisingly, be around that range of 3.5-3.8cP. On the other hand, many of the HDEO's are considerably higher, even in the same grade.

Example:
Mobil Delvac 1 ESP 0W-40:
HTHS: 4.1cP

Agree, The higher HT/HS minimum grades, like 15w-40, are other grades mostly outside of what one would use. Example: one choosing a 5w-40 isn't going to use a 15w-40. Just a good note of what I learned by reading around the net.

 

[FCD]

I'm a bit lost, what 5w40 European oil has a HTHS of 3.6?
I think Castrol Magnatec 5w30 A3/B4 is about 3.6...
Then again it is a very thick 5w30, almost a 40, +12cst @100c.

 

[edyvw]

But if HT/HS is not known it's nice to know the minimums & options of other grade variants that have a higher minimum requirements. Take a 5w-40 with no mention of it or a 15w-40 with no mention of HT/HS. You now know the 15w-40 might very well have a higher HT/HS. Still not guarantees but good to know. Like you mentioned 3.6 is just a spec above the minimum.

HTHS is not the whole story. Mobil1 0W40 is 3.6 or just bit above. But I would take it on track before pretty much any off the shelf oil.

 

[OVERKILL]

Agree, The higher HT/HS minimum grades, like 15w-40, are other grades mostly outside of what one would use. Example: one choosing a 5w-40 isn't going to use a 15w-40. Just a good note of what I learned by reading around the net.

I think it's important to differentiate between HDEO grades and Euro grades here, since the HDEO's, generally, have higher HTHS, even in the same grades as the Euros (0W-40/5W-40/10W-40), hence my D1 example, which has a much higher HTHS than your typical Euro 0W-40.

 

[OVERKILL]

I'm a bit lost, what 5w40 European oil has a HTHS of 3.6?
I think Castrol Magnatec 5w30 A3/B4 is about 3.6...
Then again it is a very thick 5w30, almost a 40, +12cst @100c.

Motul Specific 505 01 is 3.7 and Motul 8100 X-Clean 5W-40 is 3.6:

 

[edyvw]

Motul Specific 505 01 is 3.7 and Motul 8100 X-Clean 5W-40 is 3.6:

View attachment 264393

That is old Motul X-Clean. New one GEN2 is 3.9.

 

[OVERKILL]

That is old Motul X-Clean. New one GEN2 is 3.9.

Yep, but it answered the question The product is still listed on their website, along with the TDS.