Does the 2013 Lexus GS 350 have a timing belt or chain?

The 2013 Lexus GS350 is equipped with a timing chain instead of a timing belt. Most belts need replacing between 60,000-100,000 miles, but the GS350's timing chain is designed to remain maintenance free and last the lifetime of the vehicle. By default, metal chains are more durable, don't suffer from cracking or drying out like belts do, and can improve fuel economy. Chains are also more protected, operating from inside rather than outside the engine and stay lubricated. Occasionally they break or tensioners stretch, which can affect the engine adversely. Metal shavings in the oil, mIS Fires or hearing a rattling noise while idling, are indicators the chain should be examined by a mechanic.