There is no routine "service" that can be done to it. It can only be replaced and the factory recommendation mileage is every 90,000 miles.
Note: Strongly consider replacing the water pump at the same time, since the work in order to get to it is exactly the same.
The 3.3 liter V6 in a 2007 Toyota Highlander has a timing BELT
I have a 2006 Toyota highlander hybrid, do I need to change timing belt or chain?
Timing belt
Belt
The 3.3 litre V6 engine in a 2005 Toyota Highlander has a timing BELT
The 3.3 liter V6 engine in a 2006 Toyota Highlander has a timing BELT
In 2008 the Toyota Highlander V-6 engine was equipped with a timing CHAIN.
In a 2004 Toyota Highlander : The 2.4 liter four cylinder has a timing CHAIN and the 3.3 liter V6 has a timing BELT
Yes
Timing belt and water pump $500.00 - 600.00.
No. It has enclosed timing chain. Does not require replacement.
Belt - change at 90,000 miles.