Transport manager Martyn Lyne says the arrival of the new tractors coincided with that of four new Kelberg T100 bulk tipping trailers.
"We have run an MAN 6x2 with a tri-axle trailer previously on block deliveries within the fleet, and with great success," states Lyne.
"We selected MAN with this experience in mind and, importantly, because of MAN's strong reputation for building high quality trucks," he adds.
Lyne confirms that Maen Karne has not run Euro 6 vehicles before but recognised it was the future and would help improve the firm's green credentials.
He also makes the point that the local MAN dealer, Patrick Uren Commercials, is just three miles away, and undertakes regular servicing outside working hours, so minimising downtime.
"We're delighted to be working alongside Patrick Uren – another local Cornish company with whom we have a very good working relationship."
Lyne says the new fleet additions, including the new semi-trailer equipment, is part of a branding image push by Maen Karne.