When do i have to change timing chain on 2006 hummer h3?

The timing chain on a 2006 Hummer H3 is designed to last the lifetime of the engine, typically around 100,000 to 150,000 miles. However, if you notice symptoms like a rattling noise from the engine, engine misfires, or check engine light warnings, it's advisable to have it inspected. Regular maintenance and following the manufacturer's service recommendations can help determine if it needs replacement sooner. Always consult your owner's manual for specific guidelines.