1.1 ,Undesirable timing-chain wear has been observed with gasoline, turbocharged, direct-injection (GTDI) engines in field service, and data from correlating laboratory engine tests have shown that chain wear can be affected by appropriately formulated engine lubricating. A laboratory engine test has been developed to provide a means for screening lubricating oils for that specific purpose. The laboratory engine test is 216 ,h in length, conducted under varying conditions, and the increase in timing-chain length determined at the end of test is the primary result. This test method is commonly known as the Sequence X, Chain Wear (CW) Test.