I can only assume you are familiar with timing chains, but yes there are timing belts as well particularly on smaller engines.
The Ford Mustang does not have a timing belt, it has a timing chain that should last the life of the engine and requires no maintenance.
Timing Chain.
The Mustang V6 does not have a timing belt it has a timing chain which normally will last the life of the engine.
The 2.3L four cylinder equipped models do have a timing belt.
Timing chain
The 3.8 liter V6 engine in a 1996 Ford Mustang has a timing CHAIN
The V6 engine in a 2004 Ford Mustang has a timing CHAIN
It has a timing chain.
The 3.8 litre V6 engine in a 1999 Ford Mustang has a timing CHAIN
In a 1997 Ford Mustang : No timing belt The 3.8 litre V6 engine has ( 1 timing CHAIN ) The 4.6 litre V8 engine in the Mustang GT has ( 1 timing CHAIN to each cylinder head , so there are 2 timing CHAINS )
No , the 3.8 liter V6 engine in a 2000 Ford Mustang has a timing CHAIN
The 3.8 litre V6 engine in a 1998 Ford Mustang has a timing CHAIN