Does the 2012 Lexus GX460 have a timing belt or chain?

The 2012 Lexus GX460 uses a timing chain rather than a timing belt. It is better when a timing chain is used because they usually last for the life of the vehicle unlike the belt which needs to be replaced every so often. The reason why the chain should last for the life of the vehicle is because it is on the inside of the engine and it is not exposed like the belt which is outside of the engine. According to the manual from Lexus the chain requires no periodic inspection. However I would suggest inspecting it every 150,000 miles or so because in some cases the chain can fail. When inspecting it You just need to check the tension and the sprockets.