Jaguar F-Type V8 Supercharged.....0W20. Seriously?

[Berto]

Originally Posted by Smokescreen

..simple......look up what they use on that engine/car in Europe and use that.


Chevrolet Cavalier 2.2 ECOTEC users manual:

Vauxhall Astra 2.2 ECOTEC (same frigging engine, as a matter of fact manufactured in Tonawanda, NY) users manual:

So for the same engine, on one side of the pond you are told "do not use 10W-40". On the other side of the pond you are allowed up to 10W-50.

A peculiar geographical enigma, perhaps due to the Coriolis effect or the precession of the equinoxes.

 

[oil_film_movies]

Originally Posted by Patman
A lot of people believe a hard driven forced induction/DI engine should have an oil with about a 3.5 HTHS, so to go to an oil with only a 2.6 to 2.7 HTHS is about a 25% difference! That's my big issue here.
Starting from where Jaguar says is adequate, HTHS 2.6, you would only get an increase in MOFT of 15% going to HTHS 3.5, probably more "wear-safety" margin than you'd need. Going up by around +0.5 HTHS is all I'd recommend. (Outside of known heavy fuel diluters that is.)
(sqrt(3.5)-sqrt(2.6))/(sqrt(3)) = 15% difference in MOFT
(sqrt(3.1)-sqrt(2.6))/(sqrt(2.8)) = 9% MOFT increase going to a dexos1 Gen2 Full Synthetic like Mobil 1 Annual Protection 5w30, all you'd need for hard driving.....
For example, Corvettes used HTHS 3.0 for many years, and now GM wants them to have +0.5 HTHS added to that, mainly to counter occasional track racing usage.
In this Jag's case, it could be Jaguar engineers realized most of the bearing area was large enough to handle 0w20 nicely, and we want to add +0.5 HTHS to make double sure hard driving doesn't create too much wear.

 

[Garak]

Originally Posted by Treadstone
DOHC and GDI?

No. I only read half the sentence, of course.

 

[wemay]

http://www.ownerinfo.jaguar.com/document/2R/2020/T19977/33075_en_GBR/proc/G2318458

 

[wemay]

Land Rover...

https://topix.landrover.jlrext.com/...69a2e-0281-4aca-8298-083f782b8f0b/en_GB?

 

[DoubleWasp]

From what I have seen, it looks like the Jaguar specification places oils firmly in the 2.5 CST range for HTHS

 

[Gokhan]

Originally Posted by oil_film_movies
Originally Posted by Patman
A lot of people believe a hard driven forced induction/DI engine should have an oil with about a 3.5 HTHS, so to go to an oil with only a 2.6 to 2.7 HTHS is about a 25% difference! That's my big issue here.

Starting from where Jaguar says is adequate, HTHS 2.6, you would only get an increase in MOFT of 15% going to HTHS 3.5, probably more "wear-safety" margin than you'd need. Going up by around +0.5 HTHS is all I'd recommend. (Outside of known heavy fuel diluters that is.)
(sqrt(3.5)-sqrt(2.6))/(sqrt(3)) = 15% difference in MOFT
(sqrt(3.1)-sqrt(2.6))/(sqrt(2.8)) = 9% MOFT increase going to a dexos1 Gen2 Full Synthetic like Mobil 1 Annual Protection 5w30, all you'd need for hard driving.....
For example, Corvettes used HTHS 3.0 for many years, and now GM wants them to have +0.5 HTHS added to that, mainly to counter occasional track racing usage.
In this Jag's case, it could be Jaguar engineers realized most of the bearing area was large enough to handle 0w20 nicely, and we want to add +0.5 HTHS to make double sure hard driving doesn't create too much wear.

Hmm, I actually just went over a paper, which says that there is no simple correlation between the HTHSV and MOFT. The VII type and other factors make a big difference. So, it varies greatly from one oil to the next even though the HTHSV is identical.

This has been my perception for a long time. HTHSV is only a single parameter in a complex tribology problem that depends on the type of the fluids and materials used.

I will post the paper in a separate thread. It's very interesting.

Interestingly, the base-oil choice for the Mobil 1 Advanced Fuel Economy 0W-16 is PAO, and Mobil 1 Extended Performance 0w20 also uses PAO, with Mobil 1 Advanced Fuel Economy being half-PAO-based.

 

[oil_film_movies]

Originally Posted by Gokhan
Hmm, I actually just went over a paper, which says that there is no simple correlation between the HTHSV and MOFT. The VII type and other factors make a big difference. So, it varies greatly from one oil to the next even though the HTHSV is identical.
I could see that. You get a lot of different effects when the oil layer gets very small under high stress. Polymers there, surface FM, AW tribofilms, all contribute. "Film strength" can get higher if using mPAO as one example. ...... This would make the case stronger for 0w20 oils, since they can be formulated for tenacious strength near boundary conditions.