Hi there MB experts. Well, having confirmed my ticking noise as piston slap I have removed my engine, stripped it down, removed the offending No4 Piston & Conrod. Now I am trying to source a replacement. There are various numbers cast on the side of the piston & etched into the crown of the piston. Do any of these identify the specific piston I require.? My vehicle is a 110cdi Vito Type 638 2001 611980 Do any of you knowledgeable guys know if all the pistons in these 2.2 engines are interchangeable, or can offer me some advice please.