My lad has just bought a seond hand 2007 Renault Trafic SL27 DCI 115, on 109,000 miles. He asked if the cambelt had been changed before he bought it. The dealer rang Renault, who said these have a chain, so don't need changing just re tensioning. Is that correct? I've just done a bit of Googling, with various hits on cambelt changing.