Highest HTHS oils available, taking into account shear stability

But also, mechanical shear (not sheer) of the VM is highly dependent on the engine. Most engines do not place high shear loads on the oil, but some might. In those results you posted, the no-VII result shows the margin of error for the test.
He also tested a few home blended Xw-30 oils using a group 3 and PAO base along with 4 different VII. PAO/PIB resisted shear about as well as the no VII oil, but that stuff wrecked the oils winter rating.

It would be neat to see the same oil run in different engines to see if there are viscosity differences. That gets to the question of how relatable is the KRL test? If I put Mobil 1 FS 5w-50 in my mustang how quickly would I see that amount of viscosity breakdown at the track or just from daily driving?

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Thanks for the great charts. Did the home-blended oils have a complete additive package or just base oil and VIIs?
Pretty sure it was just the base + VII since all he was looking at in that video was viscosity loss
 
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But also, mechanical shear (not sheer) of the VM is highly dependent on the engine. Most engines do not place high shear loads on the oil, but some might. In those results you posted, the no-VII result shows the margin of error for the test.

They said it's the dispersants in the oil that can also shear. But there is always going to be an error in any test or measurement. I'd sign for 1% viscosity loss though.
 
As mentioned, there are 70-weight racing oils that have not been considered. Kendall ‘Nitro 70’ is another one.
 
If I put Mobil 1 FS 5w-50 in my mustang how quickly would I see that amount of viscosity breakdown at the track or just from daily driving?

We already know the answer. In the Ford 5.0, it shears in about 1500 miles of enthusiastic driving. Occasional track days or hard 'canyon' use. The 9.7% number above fits with what users see. If I remember correctly, there were short OCI tests that backed this up, but I can't find them at the moment. It may not matter much, as its loss in viscosity does not do more than drop it into the robust 40 viscosity range. With the above HTHS at 3.8.
 
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As I understand it, the 20W-50 Amsoil, M1 and Redline motorcycle oils contain no VII's. By comparison, the 5-50's and 10W-60's traditionally all did (maybe there is one now Ravenol 10W-60 that does not).

An example of a KTM 790 camshaft. Often operated on 10W-60 oil. The fact that the cam is manufactured from drop forged and heat treated chocolate has no bearing on it's rapid wear. It's the oil's fault.... (just kidding of course) It is anybody's guess whether more robust oil would help here.

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What about nitriding?

Have you heard of anyone Cryoing then nitriding?
 
All about the highest HTHS oils available, not concentrating on motorycles oils specifically, however, MC oils do tend to be high up on the list. My experience is very positive with M1's 20W-50 V-Twin oil in turbocharged race cars.

A friend with a KTM recently asked me about the most robust oils available. I suggested M1, V-Twin 20W-50 due to the superb resistance to shear and the high HTHS, which by memory is 5.9, and it is believed to be free of VII's too! Redline 20W-50 Motorcycle oil has a published HTHS of 6.1 along with similarly excellent ZDDP levels (2200/2000). The Redline might be the highest (published) HTHS 20-50 oil commonly available.

One would have to go to Amsoil racing 60 (25.0 at 100ºC) to find what I think is the absolute highest HTHS, and the specs seem to show a stunning 7.7!

Castrol Edge Supercar 10W-60 has an HTHS now said to be 5.6–5.8, (down from 6.1) and similar 10W-60 motorcycle oils are also in this range. Although with VII's the 10W-60's tend to shear fast and I don't trust the high HTHS specs to hold up for any length of time. KTM's forged chocolate camshaft wear problems might back this up.

By way of comparison, M1 15W-50 has an HTHS of 4.5. It has been a favorite of mine for OPE and turbocharged cars, as it is not a particularly viscous oil, and does exceedinly well when stepping up from a straight 30 or 10W-30/40, especially for air cooled engines. The 15W-50 falls short on brutal track days in some engines (that I may or may not have been involved with...) , when oil temps are not well controlled. An example might be during a Florida track day in a stock twin turbo V6, or even my past Turbo Honda S-2000 with 400HP and no oil cooler.

  • Mobil 1 20W-50 V-Twin: 5.9 cP
  • Red Line 20W-50: ~5.5–5.8 cP (with the motorcycle version showing a published 6.1)
  • Amsoil V-Twin 20W-50: ~5.6 cP; Dominator 20W-50: 5.5 cP (estimated)
  • Motul 300V 15W-50: 5.33 cP
  • Ravenol RSS 10W-60: 5.7 cP
  • HPL Euro 10W-60: ~5.5+ cP (estimated)
  • Castrol Edge 10W-60: 5.6–5.8 cP, possibly 6.0 cP historically, but not now.
  • Highest worldwide: Straight SAE 60, Amsoil 7.7
MaKGi0ol.jpg
As I big Honda nut I would love to go for a ride, but being tall and heavy it would be a short one as I get cramped easily. Id like to ride or drive the newer Civic Type R but it needs a plush Accord seat that goes back another 4-6 inches at least. Nice car!!!
 
All about the highest HTHS oils available, not concentrating on motorycles oils specifically, however, MC oils do tend to be high up on the list. My experience is very positive with M1's 20W-50 V-Twin oil in turbocharged race cars.

A friend with a KTM recently asked me about the most robust oils available. I suggested M1, V-Twin 20W-50 due to the superb resistance to shear and the high HTHS, which by memory is 5.9, and it is believed to be free of VII's too! Redline 20W-50 Motorcycle oil has a published HTHS of 6.1 along with similarly excellent ZDDP levels (2200/2000). The Redline might be the highest (published) HTHS 20-50 oil commonly available.

One would have to go to Amsoil racing 60 (25.0 at 100ºC) to find what I think is the absolute highest HTHS, and the specs seem to show a stunning 7.7!

Castrol Edge Supercar 10W-60 has an HTHS now said to be 5.6–5.8, (down from 6.1) and similar 10W-60 motorcycle oils are also in this range. Although with VII's the 10W-60's tend to shear fast and I don't trust the high HTHS specs to hold up for any length of time. KTM's forged chocolate camshaft wear problems might back this up.

By way of comparison, M1 15W-50 has an HTHS of 4.5. It has been a favorite of mine for OPE and turbocharged cars, as it is not a particularly viscous oil, and does exceedinly well when stepping up from a straight 30 or 10W-30/40, especially for air cooled engines. The 15W-50 falls short on brutal track days in some engines (that I may or may not have been involved with...) , when oil temps are not well controlled. An example might be during a Florida track day in a stock twin turbo V6, or even my past Turbo Honda S-2000 with 400HP and no oil cooler.

  • Mobil 1 20W-50 V-Twin: 5.9 cP
  • Red Line 20W-50: ~5.5–5.8 cP (with the motorcycle version showing a published 6.1)
  • Amsoil V-Twin 20W-50: ~5.6 cP; Dominator 20W-50: 5.5 cP (estimated)
  • Motul 300V 15W-50: 5.33 cP
  • Ravenol RSS 10W-60: 5.7 cP
  • HPL Euro 10W-60: ~5.5+ cP (estimated)
  • Castrol Edge 10W-60: 5.6–5.8 cP, possibly 6.0 cP historically, but not now.
  • Highest worldwide: Straight SAE 60, Amsoil 7.7
MaKGi0ol.jpg
Looks like a good list. I was going to say if you want shear stability stay away from PP and PUP 5w-30.
 
not joking, the car eats oil for breakfast. it needs valve stem seals.
You have probably tried these kinds of things already. Obviously, you are trying to avoid rebuilding the head, or entire engine. Go to Amazon and order a couple cans of Liqui Moly Motor Oil Saver, part # 2020, follow the directions. I know from personal experience that Liqui Moly does make some decent snake oil products. https://pim.liqui-moly.de/pdf/en_US/liqui/56/P000002
 
You have probably tried these kinds of things already. Obviously, you are trying to avoid rebuilding the head, or entire engine. Go to Amazon and order a couple cans of Liqui Moly Motor Oil Saver, part # 2020, follow the directions. I know from personal experience that Liqui Moly does make some decent snake oil products. https://pim.liqui-moly.de/pdf/en_US/liqui/56/P000002
i have it in my car now. my oil consumption has gone done substantially. it will only burn it if i let it idle for 10+ minutes now.
 
i have it in my car now. my oil consumption has gone done substantially. it will only burn it if i let it idle for 10+ minutes now.
Liqi Moly makes some decent snake oils. Actually, they have some decent engine oils too. Are they Red Line or Amsoil, no, but they are decent. From Germany, though you probably knew that.
 
Liqi Moly makes some decent snake oils. Actually, they have some decent engine oils too. Are they Red Line or Amsoil, no, but they are decent. From Germany, though you probably knew that.
i would’ve tried anything other than lucas to get the burning to slow down.
 
i would’ve tried anything other than lucas to get the burning to slow down.
Their Mos2 product save me several Hundred dollars awhile back on the 2015 Honda CRV I traded in on my current 2025 Toyota Rav4. Ever since then I add a can of the Mos2 product at every oil change, even my new Toyota, does it do any good, who knows, but it doesn't hurt anything. Good product in my opinion.
 
Their Mos2 product save me several Hundred dollars awhile back on the 2015 Honda CRV I traded in on my current 2025 Toyota Rav4. Ever since then I add a can of the Mos2 product at every oil change, even my new Toyota, does it do any good, who knows, but it doesn't hurt anything. Good product in my opinion.
i run HPL oils so i don’t think i need anymore wear protection (5w-40), i just needed something to swell up the old valve seals.
 
As I understand it, the 20W-50 Amsoil, M1 and Redline motorcycle oils contain no VII's. By comparison, the 5-50's and 10W-60's traditionally all did (maybe there is one now Ravenol 10W-60 that does not).

An example of a KTM 790 camshaft. Often operated on 10W-60 oil. The fact that the cam is manufactured from drop forged and heat treated chocolate has no bearing on it's rapid wear. It's the oil's fault.... (just kidding of course) It is anybody's guess whether more robust oil would help here.

img_4518-jpeg.61744
IMG_9669.webp
IMG_9669.webp
IMG_9670.webp


Here are the Lobes on my 2024 KTM 790 at almost 13k miles. Ran mostly on Amsoil 15w50 Metric which has an HTHS of 5.7cp
 
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