{"product_id":"schaeffer-manufacturing-co-synshield-otr-plus-5w-40-full-synthetic-diesel-engine-oil-1-quart-api-ck-4","title":"Schaeffer Manufacturing Co SynShield OTR Plus 5W-40 Full Synthetic Diesel Engine Oil, 1-Quart, API CK-4","description":"\u003cp\u003e\u003cstrong\u003eSchaeffer SynShield OTR Plus 5W-40 is a full synthetic diesel engine oil engineered to protect heavy-duty diesel engines, improve fuel economy, and resist soot and deposits.\u003c\/strong\u003e\u003c\/p\u003e\n\n\u003cp\u003eSchaeffer Manufacturing Co. SynShield OTR Plus 5W-40 is a synthetic-plus, heavy-duty engine lubricant formulated for modern diesel powerplants that face high soot levels, heavy EGR duty and exhaust aftertreatment systems. This 1-quart bottle meets API CK-4 performance and is built with friction modifiers including Micron Moly and Penetro to lower metal-to-metal wear while preserving fuel economy and thermal stability in demanding service.\u003c\/p\u003e\n\n\u003ch3\u003eHow does SynShield OTR Plus 5W-40 protect engines under heavy soot and high temperature?\u003c\/h3\u003e\n\u003cp\u003eThe formulation resists oxidation and deposit formation to keep oil chemistry stable under high thermal stress and soot loading. Specialized dispersants and detergents help suspend soot and prevent abrasive buildup, while robust base stocks maintain film strength at higher temperatures.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eSynthetic base oils for improved heat resistance and durability.\u003c\/li\u003e\n  \u003cli\u003eSoot-dispersing additives reduce abrasive particle buildup.\u003c\/li\u003e\n  \u003cli\u003eOxidation inhibitors slow oil thickening and preserve viscosity.\u003c\/li\u003e\n  \u003cli\u003eFriction modifiers (Micron Moly, Penetro) minimize wear during heavy loads.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWill this oil work with engines that have DPFs, DOCs or SCR systems?\u003c\/h3\u003e\n\u003cp\u003eYes — SynShield OTR Plus 5W-40 is suitable for modern emission-controlled diesel engines, including those equipped with diesel particulate filters and oxidation catalysts. It’s formulated to be compatible with exhaust aftertreatment devices while meeting API CK-4 durability standards.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eCompatible with DPF and DOC-equipped engines when used per manufacturer guidance.\u003c\/li\u003e\n  \u003cli\u003eDesigned for heavy EGR duty and soot-prone applications.\u003c\/li\u003e\n  \u003cli\u003eAPI CK-4 rating aligns with contemporary diesel OEM recommendations.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eHow does this oil affect cold starts and fuel economy?\u003c\/h3\u003e\n\u003cp\u003eThe 5W cold-start rating improves low-temperature flow for faster oil circulation on startup, helping protect critical components during initial crank. The friction modifiers help reduce internal drag, which can contribute to better fuel economy without sacrificing protection.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003e5W viscosity for improved cold-weather pumpability.\u003c\/li\u003e\n  \u003cli\u003eFriction reduction additives lower parasitic losses for efficiency gains.\u003c\/li\u003e\n  \u003cli\u003eMaintains protection across a wide temperature range to balance economy and durability.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eHow often should I use this oil and in what service conditions is it best?\u003c\/h3\u003e\n\u003cp\u003eOil change intervals depend on duty cycle, hours, load and manufacturer recommendations, but SynShield OTR Plus is aimed at extended service where soot control and thermal stability are critical. Monitor oil analysis results where possible to tailor intervals for severe or continuous heavy-duty use.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eIdeal for on-highway, vocational, and off-highway heavy-duty diesel use.\u003c\/li\u003e\n  \u003cli\u003eRecommended for engines with heavy EGR or high soot generation.\u003c\/li\u003e\n  \u003cli\u003eUse oil analysis to optimize drain intervals in severe service.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003eWho is this for: Schaeffer SynShield OTR Plus 5W-40 is intended for fleet managers, owner-operators and technicians running modern heavy-duty diesel engines that require API CK-4 level protection, especially machines operating under high soot, heavy loads, low-temperature starts, or with emission aftertreatment systems. Choose this oil when you need a balance of deposit control, wear protection and fuel-economy-minded lubrication in a one-quart convenient size for top-offs and service work.\u003c\/p\u003e\n\u003csection class=\"product-faq-snippet\"\u003e\u003ch3\u003eFAQ\u003c\/h3\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cp class=\"faq-q\"\u003eQ: Is Schaeffer SynShield OTR Plus 5W-40 compatible with diesel particulate filters?\u003c\/p\u003e\n\u003cp class=\"faq-a\"\u003eA: Yes. It’s formulated for engines with DPFs and DOCs when used according to the engine manufacturer’s guidance.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cp class=\"faq-q\"\u003eQ: Does this oil meet API CK-4 specifications?\u003c\/p\u003e\n\u003cp class=\"faq-a\"\u003eA: Yes. SynShield OTR Plus 5W-40 is formulated to meet API CK-4 performance requirements.\u003c\/p\u003e\n\u003c\/div\u003e\u003c\/section\u003e","brand":"Schaeffer Manufacturing Co","offers":[{"title":"Default Title","offer_id":55163567145303,"sku":"B08BVVVSRL","price":32.08,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1050\/1524\/7191\/files\/schaeffer-synshield-5w40-front-packaging.jpg?v=1790345526","url":"https:\/\/britishgarage.co.uk\/products\/schaeffer-manufacturing-co-synshield-otr-plus-5w-40-full-synthetic-diesel-engine-oil-1-quart-api-ck-4","provider":"British Garage","version":"1.0","type":"link"}