Highest xW-20 Viscosity @ 100°C?

[UNC151]

I see Red line with 9.1; is there any higher? Conversely, what is the highest viscosity @ 100°C that can still be called an xW-20?

TIA!

 

[PimTac]

https://www.bobistheoilguy.com/viscosity-charts/

 

[UNC151]

https://www.bobistheoilguy.com/viscosity-charts/

Thanks Bud--forgot about those

 

[ZeeOSix]

I see Red line with 9.1; is there any higher? Conversely, what is the highest viscosity @ 100°C that can still be called an xW-20?

TIA!

Per SAE J300 (the official definer of motor oil viscosity ratings), it shows SAE 20 must be 6.9 to
So 9.1 cSt is almost at the thick end of SAE 20.

https://www.widman.biz/English/Tables/J300.html

 

[UNC151]

I am playing around a bit with Widman's calculator and RGT. I scored 115QTs of 0W-20 and 60QTs of 5w30. The middle mix (2QTs of 5w30 and 3 QTs of 0W-20) is a nice blend and makes a very thin xW-30 or a very thick (just out of the viscosity range) xW-20:

 

[bbhero]

I would go by HTHS... More straight forward that way. And at 150°C it is what oil temps are in the bearings.

I think Mobil 1 Extended Performance 5w20 has a HTHS of 2.7. One of the "thicker" 20 operating temp viscosity oils.

 

[UNC151]

I would go by HTHS... More straight forward that way. And at 150°C it is what oil temps are in the bearings.

I think Mobil 1 Extended Performance 5w20 has a HTHS of 2.7. One of the "thicker" 20 operating temp viscosity oils.

Unfortunately, I have not found those values posted anywhere for RGT, so cSt is the only other common number between the two oils which is available.

 

[4wd]

Unfortunately, I have not found those values posted anywhere for RGT, so cSt is the only other common number between the two oils which is available.

Well, there is always the “unsurpassed wear protection“ claim …

 

[OilUzer]

I would kill two birds with one stone and move up to a non a3/b4 xW30 if I were in search of the thickest xW20.

 

[UNC151]

I would kill two birds with one stone and move up to a non a3/b4 xW30 if I were in search of the thickest xW20.

I have too much RGT in 0W-20 and 5w30 to do that. I will just blend it and use it in the Jeep and Explorer.