I lack information for when to change timing belt. My Volvo is 121k miles. Thanks for anyone's help.

 

Here's a handy link for all. https://www.volvotechinfo.com/index....ltInterval.pdf

Assuming your car has a six cylinder, you don't have a timing belt.

Note the B code for your engine should be on a sticker on the timing belt cover. Translating the codes is simple. For example:
B6304T4 - B means its a gas engine, 6 cylinders, 3.0L displacement, 4 valves per cylinder, Turbocharged (S is natural aspiration), 4th generation.