ACEA C6-21
ACEA C6 is a new category for ACEA 2021 and focuses on Premium mid Sulphated Ash, Phosphorus and Sulphur (SAPS) lubricants. They are designed for use in high performance gasoline and light duty diesel engines with extended service intervals, where advanced aftertreatment systems such as Diesel Particulate Filters (DPFs) and Three Way Catalysts (TWC) are used.
ACEA C6 oils feature a low minimum HTHS viscosity of 2.6cP and brings into focus Low Speed Pre-Ignition (LSPI), Turbo Charger Wear and Turbo Charger Compression Deposit (TCCD) protection.
The main physical and chemical requirements for ACEA C6 are shown below:
| Requirement | Method | Unit | Limit |
| HTHS viscosity | CEC L-036-A-90 | mPa.s | ≥ 2.6 and < 2.9 |
| Sulphated Ash | ASTM D874 | %m/m | ≤ 0.8 |
| Phosphorus |
ASTM D5185 |
%m/m | ≥ 0.07 / ≤ 0.09 |
| Sulphur | ASTM D5185 ASTM D4951 |
%m/m | ≤ 0.3 |
| Evaporation loss (NOACK) | CEC L-40-A-93 | % | ≤ 13 |
| Total Base Number | ASTM D2896 ASTM D4739 |
mgKOH/g | Report ≥ 4.0 |
ACEA C6 builds on the performance levels set by ACEA C5 bringing in specific tests focusing on LSPI and Turbo charger protection, whilst introducing new fuel economy testing.
The new tests introduced as part of ACEA C6 are summarised below:
| Test | New Engine Tests for ACEA 2021 |
| CEC L-107-19 | M271 EVO Sludge |
| ASTM D8256 Sequence VH | Low Temperature Sludge |
| ASTM D8350 Sequence IVB | Valvetrain Wear |
| CEC L-117-20 | VW TDI 3 Deposits |
| JASO FE M366 | Fuel Economy Improvement |
| CEC L-114-19 | Turbo Charger Compressor Deposit Rating |
| ASTM D2891 Sequence IX | Low Speed Pre-Ignition (LSPI) Events |
| ASTM D8279 Sequence X | Elongation of Timing Chain |