Fiat 9.55535-DM1

The FIAT specification 9.55535‑DM1 defines a synthetic engine oil with a viscosity of 5W‑40 (or 0W‑40) and high oxidation stability, providing wear protection, deposit control, and maintaining high‑pressure sealing in modern Fiat diesel engines. The requirements include compliance with ACEA C3, API CJ‑4 and a low SAPS content, making this oil compatible with after‑treatment systems – diesel particulate filters (DPF) and catalysts. The specification is targeted at MultiJet, MultiJet II, MultiJet 2.2‑2.5 diesel units, as well as diesel variants of Jeep, Alfa Romeo and other Stellantis models that require cavitation protection and fuel‑economy preservation. Oils approved under 9.55535‑DM1 also meet the older FIAT 9.55535‑DS1 requirements, allowing safe use in engines that previously ran on earlier specifications. Using such oil ensures compliance with the manufacturer’s warranty conditions and extends engine life, reducing the risk of DPF fouling.