Castrol GTX is one of the world's most trusted motor oils. It's more than just oil. It's liquid engineering that protects against problems, like sludge, that your engine faces every day. Severe driving conditions such as every day stop-and-go/stop-start traffic, harsh weather conditions and extended drain intervals, can all cause the build-up of a thick, tar-like substance called sludge. You can't see this sludge build-up but it can damage your engine's performance and cause premature engine failure. Protect your car from harmful sludge build-up with Castrol GTX. Application GTX 15W-40 A3/B3 is suitable for use in automotive gasoline and diesel engines where the manufacturer recommends an API SL/CF or ACEA A3/B3 15W-40 lubricant. GTX 15W-40 A3/B3 is also approved for use in VW group vehicles and Mercedes Benz vehicles that require a VW 501 01/ 505 00 or MBApproval 229.1 15W-40 lubricant Advantages Contains anti-sludge formula that provides 25% better sludge protection compared to tough industry standards Superior protection against viscosity and thermal breakdown Anti-wear additives that extend the life of your engine Product Performance Claims ACEA A3/B3 API SN MB-Approval 229.1 VW 501 01 / 505 00 Meets Fiat 9.55535-D2