Hi This is a problem I forgot I had as it only happens when the engine is well warmed up on a long journey. ( A thing that I Dont do too often) But every so often I get a tappet noise coming from the engine when it revs above 2200 rpm going up through the gears. Last time i took off the rocker cover for a nosey but couldnt see anything obvious- Not too familiar with the 2.5 4d56 . if I could get some pointers on where to start looking rather than ripping things to bits that would be great

Did you check the tappet clearance when you were noseying around ?