The Ford Mondeo 1.8 diesel engine has a wet belt in the sump.
It also has a normal timing belt on top to drive the inj pump and cam.
This engine is known as the lynx engine. Fords used to use a timing chain (the old way) in the sump now they decided to use a wet belt (rubber belt). Its hard to know if your car has chain or wet belt without stripping it down but the info can be got from a ford garage by the chassis number. It was around 2008 they changed but also depends on date some were registered late or early.
They say using the wrong grade of oil can degrade the wet belt also by missing regular servicing.
Any belt i'v changed has been very badly cracked and worn! even at low mileage, as little as 90,000 miles.