J&L Oil Separator Co. — Proven Protection for Modern Engines

A J&L oil separator, also known as a catch can, is a device that captures oil mist and blow-by gases from your engine’s crankcase ventilation system before they can re-enter the intake. It routes these vapors through a high-efficiency filter inside a billet aluminum canister, trapping the oil while allowing clean air to pass through. This helps prevent carbon buildup, keeps intake valves cleaner, and protects engine performance over time.

Most modern engines, especially those with direct injection or forced induction—benefit from an oil catch can. Blow-by is a natural byproduct of combustion, and over time, oil vapors can coat intake valves and reduce efficiency. Installing a J&L oil separator helps minimize carbon buildup, maintain power, and extend engine life, making it a worthwhile upgrade for daily drivers, performance vehicles, and work trucks alike.

While the core function is the same, J&L designs each oil separator kit to fit the unique requirements of different vehicles. Car-specific kits are engineered for performance and fitment in tighter engine bays, often targeting direct-injection or turbocharged engines. Our truck kits are built to handle higher crankcase pressures from towing, hauling, or off-road use, with robust filtration and easy installation for heavy-duty applications.

Yes, the terms “catch can” and “air oil separator” are often used interchangeably. Both devices serve to separate oil from crankcase vapors before those vapors return to the intake system. J&L’s products are engineered as high-efficiency air/oil separators, offering advanced filtration and easy servicing.

It’s recommended to check and empty your J&L oil separator within 1000 miles after initial installation. Most owners can go up to 3,000–4,000 miles under normal use before filling the standard 3oz reservoir, though this can vary depending on your driving style, climate, and engine condition. In cold weather or under heavy use, check more frequently. Periodically clean the separator and its filter (about every 12,000-15,000 miles) for optimal performance. If you are looking for additional capacity for the oil separator, we do offer a reservoir extension that is compatible with many of our popular applications.

Generally, installing an oil separator will not void your vehicle’s warranty. The Magnuson–Moss Warranty Act protects consumers, meaning a manufacturer must prove an aftermarket part caused a failure to deny warranty coverage. If you have concerns, check with your dealer or service department for clarification.

Yes, J&L offers vehicle-specific kits designed for a factory-quality fit and easy installation—no cutting or tuning required. Each kit is engineered for the engine bay it’s intended for, ensuring reliable performance and a clean, professional look. Universal kits are also available for custom applications.