Intriguing post from Bob
I use these oils as my father is a dealer in France.
There is no dealer outside Europe.
All their oils are ACEA A3 rated at least, except the 15W60 non graphited dino (not listed on their website).
I've used the Carat-S which is currently ACEA A3/B3/C3 and complies with many EU car makers specs, from 45K to 50,35K miles with an OCI at 50K. I crashed my car then, changed the body and need to spend several hundred € to buy dead electronic parts.
My current mix is the same model of car is a group 3 A3 rated 5W40 -their lowest oil quality- with a graphite/MoS2 additive.
Engine is 136hp 1.4L 8V turbocharged, with 81.4K miles.
I'll swith back to the carat S for my next OCI (every 4661 miles or 7 500 kms).
If I tune my engine (injectors, turbo, intercoler, cams...), I'll use the ester based "Bio Carat", very robust in competition use.
Marly is a solid lubricant specialist since 1919 and uses graphite in automotive products since 1930.
They use graphite and moly (SX oil additive which is a gaphite + MoS2 combinaison in synthectic fluids) for decades, and are also a special lubricants maker.
Graphite particles are <1µ and never caused damages from what I know with the Black Gold oil range.
These oils apparead in 1977 and have always been formulated with a colloidal suspension of graphite particles.
Graphite oils failed to be largely used because of the dark colour, people think dark oil is used oil