ACEA C4-21
ACEA C4 oils are Top Tier low 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 C4 oils feature a low minimum HTHS viscosity of 3.5cP and are typically SAE 5W-30 based on API Group III base oils.
The main physical and chemical requirements for ACEA C4 are shown below:
| Requirement | Method | Unit | Limit |
| HTHS viscosity | CEC L-36-90 | cP | ≥ 3.5 |
| Sulphated Ash | ASTM D874 | %m/m | ≤ 0.5 |
| Phosphorus | ASTM D5185 or ASTM D4951 |
%m/m | ≤ 0.09 |
| Sulphur | ASTM D5185 or ASTM D4951 |
%m/m | ≤ 0.2 |
| Evaporation loss (NOACK) | CEC L-40-93 | % | ≤ 11 |
| Total Base Number | ASTM D2896 and ASTM D4739 |
mgKOH/g | ≥ 6.0 Report |
There are a limited number of associated OEM specifications to ACEA C4.
- Renault RN0720
- MB 226.51
ACEA C4 was first introduced into the ACEA Oil Sequences in 2007 and has seen significant changes since its introduction, most recently in the ACEA 2021 update.
The inclusion of the new VW TDI3 Engine Test and M271 Evo Sludge Test represent two of the more significant changes to the category, updating test requirements to match modern engine hardware including the increased usage of Turbo Charged Gasoline Direct Injection (TDGI) Engines.
| Test | Additional tests for ACEA 2021 |
| CEC L-107-19 | M271 EVO Sludge |
| CEC L-117-20 | VW TDI Piston Cleanliness (TDI3) |
| ASTM D8256 Sequence VH | Low Temperature Sludge |
| ASTM D8350 Sequence IVB | Valvetrain Wear |