Hi,
OT - Mobil has variously used "SHC" in labeling their fully synthetic product descriptions for some decades. With semi-synthetics they have typically used "synthetic enriched" and some other descriptors
They have used SHC in their Gargoyle Artic lubricants with a vis of 1cSt @ 100C and in their greases! Mobilgard 1 SHC is a Marine lubricant with a pour point of -54C and SHC appeared in gear oil descriptions but not in their fourth generation synthetic Jet oils! Their SHC gear oils - excellent products - contained "synthesised hydrocarbons and carefully selected esters"
Delvac 1 5W-40 had the following description in 1998 (CH-4/SJ):
"Mobil Delvac 1 is formulated with synthetic base oils made in Mobil's own chemical plants, and specially developed additve components which ensure the best product performance. The base oils are not conventional PAO and esters - which although pioneered by Mobil - are now in widespread use today. They are based on a unique Mobil cyclic hydrocarbon fluid for the best engine wear protection"
and this:
"Hydroprocessing can successfully remove many undesirable constituents such as aromatics, some paraffins, nitrogen and sulphur, and improve oxidation stability.However, though hydroprocessing is a valuable addition to the basic refining and blending process, it adds cost and cannot provide all the requirements of a modern top grade oil. To achieve the ultimate level of protection and longevity, the oil needs to use a completely different type of base stock called a synthetic"
One version was called Delvac 1 SHC 5W-40
Currently, the German version of Mobil 1 ESP 5W-30 has the "Official" product description as "Synthetic base oil and Additives". It includes SuperSyn
It appears that it is one of the latest versions-formulations of an ever evolving M1 product range and it may be a quantum leap forward like M1 0W-40 was nearly 10 years ago!
Mobil lubricants available here in Australia still include a number of semi-synthetic nomenclatures - Synth and Synth S (being phased out) and Mobil 2000 in a number of variations.
Formula S and S2 and Formula X2 are another three Mobil semi-synthetics - with Manufacturer Approvals as well
The "fully synthetic" Mobil 3000 range of lubricants was introduced about two years ago. The 3000 range has a number of specialised variation in some Markets and some Manufacturer Approvals such as Porsche
Three variations of Mobil 3000 which are described as "fully synthetic" are Listed by VW-Audi they are 3000 x 1, 3000 x 2, 3000 x 2 Turbo Diesel and all have a 5W-40 viscosity
As I indicated about two years ago it is my understanding that WW Mobil's lubricant product lineup will probably be;
M1 - Premium fully synthetic lubricant range (with Manufacturer Approvals)
1000 - Baseline "consumer" product range
2000 - Semi-synthetic range and labeled as such
3000 - Fully synthetic range (with Manufacturer Approvals) to compete with other Oil Companies
4000 - NIA
5000 - A "segment" baseline lubricant range with ester components in its Patent
6000 - NIA
7500 - Semi-synthetic range
But then I could be wrong.....................................!
So Mobil's use of the "SHC" title for lubricants (including their Delvac Commercial-Industrial range of lubricants) has a long term background over several decades. This transcends the Mobil-Castrol "synthetics" terminology "battle" of several years ago. The SHC title is variously being used WW by them today covering their broad range of fully synthetic lubricants. Their semi-synthetic (or blend) lubricants do not appear to carry this title
Regarding HTHS vis. - what is known as GC (Castrol's Formula SLX 0W-30) once had Porsche Approval. This was withdrawn around 1999 as it did not meet IIRC the extended HTHS and 100C viscosity protocols required by Porsche
I have no Commercial relationship with any Oil Company!