What is the average mileage most owners change the timing belt on 2009 Hyundai Santa Fe 2.7L V-6 engine. The owners manual says at 75000 miles but I bet most owners go to 100,000 miles or so.Any current owners have any experience?

 

Re-read your manual.
It says 75,000 miles OR 60-months.
60 months is 5 years.
5 years from 2009 is 2014.
This year is 2015.

Change it at 75,000 or else: https://www.hyundaiforum.com/forum/h...ow-miles-8006/

 

If you change the timing belt then you should consider using a kit that has the tensioner, idler pulley and the associated stuff that spins along with your timing belt.

If you wait then you run the risk of belt failure which can cost thousands of dollars to fix
It is really a matter for the owner to consider and make their own choices