Has Mercedes Always Been This Bad?

cav551:
An extemely scruffy and very rough sounding 63 reg Turners’ Merc appeared today with a load of Kappa, on what looked like a brand new Jack Richards trailer. It was so bad I just wondered if it got back before it expired.

The '63 plates are all high mileage units to be fair, typically 1.2 million Km, and they are being replaced. They do sound rough at the best of times, I had wondered if they have a different cylinder firing order to such as DAF, Volvo and Scania engines?