Dexos R: What is it exactly?

[altaylar]

Do we have any information on what Dexos R tests for exactly?

@OVERKILL posted the following on another thread, and that is about all I could find on it. Is this this essentially a "Porsche A40/C40" equivalent, with a GM stamp on it?
But then, why does Pennzoil Ultra Platinum 0W40 has Dexos R, and not Pennzoil Platinum Euro 5w40 which is a Euro version and what BITOG community considers superior to Pennzoil Ultra Platinum at that grade?

My understanding of the evolution was:

dexos1 -> Typical GM gas engines

dexos2 -> Typical GM diesel engines

dexos2 was carried by Mobil 1 ESP 0W-40 and X3 0W-40.

dexos2 was then spec'd for high performance gas engines, like the LT1 and LT4

GM split dexos2 into dexosD (diesel) and dexosR (high performance gas)

Since dexos2 was already mostly based on Euro OE sequences, its gas successor, dexosR, could be transferred to oils that met those performance requirements, regardless of whether they were mid or full-SAPS. GM had Mobil produce a GM-specific "supercar" oil that carried the dexosR approval with the intention of that being the default product, but lack of availability forced the extension of the approval to the current slate of offerings:

 

[buster]

WPD avg is set to 5.4 min. A rating of 5.5 for piston deposits after 100 hours of testing is commonly considered outstanding. GF-7 as a comparison is set to 4.6min. dexos also incorporates a few European tests. I'd actually consider this a good spec to go by for piston cleanliness vs typical GF-7 oils.

We also know Mobil 1 SuperCar exceeds them.

"We were trying to put together an oil that would just crush all of those tests and well exceed the limits for those, "Salvesen says

 

[altaylar]

I asked Gemini how it differs from MB 229.5

It says MB229.5 focuses more on long drain interval things (Oxidation durability, High TBN, more detergency) and full saps
Whereas Dexos R is more cat friendly, and focuses more on LSPI (Lower Ca) and more anti foaming (due to GM's cylinder deactivation etc. calling for it).

More readings to do...

 

[DCDG]

Didn't know Dexos R existed Google answered all that needed to be known.

 

[buster]

It's a good spec the more I look at it. Certainly good for piston deposit control relative to GF-7 standards.

 

[OVERKILL]

Do we have any information on what Dexos R tests for exactly?

@OVERKILL posted the following on another thread, and that is about all I could find on it. Is this this essentially a "Porsche A40/C40" equivalent, with a GM stamp on it?
But then, why does Pennzoil Ultra Platinum 0W40 has Dexos R, and not Pennzoil Platinum Euro 5w40 which is a Euro version and what BITOG community considers superior to Pennzoil Ultra Platinum at that grade?

If Afton ever decided to release another handbook, we'll have the same level of detail as we had for dexos 1 and 2.

 

[chris719]

It's pretty clear based on lineage that dexosR is a successor to dexos2 which was an ACEA C3 oil, so dexosR is basically the GM gasoline variant of Euro oils, with some allowances for certain API/ILSAC 0W-40s like the Pennzoil Ultra Platinum.

 

[OVERKILL]

It's pretty clear based on lineage that dexosR is a successor to dexos2 which was an ACEA C3 oil, so dexosR is basically the GM gasoline variant of Euro oils, with some allowances for certain API/ILSAC 0W-40s like the Pennzoil Ultra Platinum.

And full-SAPS oils (A3/B4) like FS 0W-40.

 

[VolkswagenFox21]

Saw this on the dexos website:
"Please note: GM dexos R engine oils meet or exceed the performance of GM dexos 2 and GM dexos 1 Gen 2 and Gen 3 oils and are backward compatible, therefore vehicles equipped with gasoline engines that used GM dexos 2, or GM dexos 1 Gen 2 or Gen 3 may use a GM dexos R licensed engine oil of the appropriate viscosity grade at their next oil change."

So when in doubt use some sort of flavour of Mobil 1 0W-40. Sounds good to me. More proof that the "Mobil 1 0W40 in everything" crowd is generally correct.

 

[4wd]

Saw this on the dexos website:
"Please note: GM dexos R engine oils meet or exceed the performance of GM dexos 2 and GM dexos 1 Gen 2 and Gen 3 oils and are backward compatible, therefore vehicles equipped with gasoline engines that used GM dexos 2, or GM dexos 1 Gen 2 or Gen 3 may use a GM dexos R licensed engine oil of the appropriate viscosity grade at their next oil change."

So when in doubt use some sort of flavour of Mobil 1 0W-40. Sounds good to me. More proof that the "Mobil 1 0W40 in everything" crowd is generally correct.

Think my L84 has entered the chat room