Castrol GTX Classic 20W-50 Conventional Motor Oil, 1 Quart, Pack of 6

The Castrol GTX Classic 20W-50 Conventional Motor Oil, 5 Quart Jug is a high-performance conventional oil formula for classic and collector cars as well as racing applications. It is blended with high zinc (1400 ppm) and phosphorus content to help prevent premature aging, wear, and metal fatigue on engines with high tension valve springs or performance modifications that create high contact pressure and extreme internal temperatures. This engine oil is specially formulated for classic/collector cars, muscle cars, hot rods, and race cars. Castrol GTX Classic 20W-50 is suitable for use in automotive gasoline engines where the manufacturer recommends an API SJ or earlier specification 20W-50 lubricant. This oil is not for use in modern engines with catalytic converters or wet clutch applications. Many positive reviews suggest that this oil is perfect for older engines, including air-cooled VW engines, MG Midgets, and classic cars. Customers described it as holding up well in extreme conditions and providing the necessary additives to keep older engines alive. Notably, this oil provided zinc protection insurance during extreme cold weather startups. Other reviews suggest that the oil reduces leaks in older cars and is perfect for non-emission applications. One review suggested Castrol GTX Classic 20W-50 is a nostalgia oil for old VWs and Corvair owners.