The belt on a Mondeo TCDI Duratorq 56 plate is part of the timing chain/belt. The timing chain and belt should be checked at 100K miles. The belt and the chain work together in the running of the engine.
On a 2007 Ford Ranger 2.5 TDCi, the diesel filter is typically located on the driver's side of the engine bay, near the front of the engine. It is mounted to the chassis or engine and is often cylindrical in shape. To access it, you may need to remove any obstructing components or covers. Always consult the owner's manual for specific details and safety precautions when working on your vehicle.