We had NLG 443H a TGM Mercury artic that had a Pitt Tandem 4 lightweight 30’ trailer behind it. With a GVW of 26 tons it tared off at exactly 7 tons giving 19 tons payload, not much behind a Mandator. I once loaded 2 Caterpillar bulldozers down in Surrey to fetch back up to Manchester, the trailer was like a bannana, but not a murmer of protest from the Mercury. I do recall the trailer tyres got a bit warm though. 