Narrowly surpassing the Hyundai i30 CRDi which previously achieved an average of 3.2-litres per 100km, John and Helen Taylor driving the Peugeot 308 HDi managed a slightly more efficient 3.13-litres per 100km across a 25 Day Round Australia Trip.
This also breaks the previous official record held by the Peugeot 307 which managed an average of 3.49-litres per 100km.
Over the 14,580km journey, the 308 HDi needed only 7.59 tanks or 453.94 litres of diesel in total, costing a mere $703.93.
Its best tank achieved 1988km from 58.98 litres, with the average falling slightly below this mark at 1919km.
The 308 was also fitted with Michelin Energy XM1+ Tyres, which offer a lower rolling resistance via innovative technology that actually reduces fuel consumption.
The specific model used in the record attempt was a 308 XS HDi manual which has an RRP of $29,990. Featuring a 1.6 litre turbo-diesel engine, it produces 80kW of power and 240Nm of torque.