A southbound B-double, which police said was laden with general freight and weighed 60.7 tonnes, was stopped by officers after its speed was detected at 150km/h about 9am on Saturday.

In NSW, the maximum speed limit for a vehicle with a gross mass of more than 4.5 tonnes is 100km/h. Trucks exceeding 15 tonnes GVM are fitted with speed limiter devices that restrict their speed to 100km/h.

Officers pulled the truck over and escorted it to the NSW Roads and Maritime Services (RMS) heavy vehicle safety station at Marulan for an inspection.

Data from the vehicle's engine control module was also downloaded.

The 45-year-old driver, from the south-western Sydney suburb of Horningsea Park, was issued an infringement for exceeding the speed limit by more than 45km/h.

He was fined $3691, stripped of six demerits points and had his licence suspended for six months.

According to police, the inspection of the truck identified a minor defect on the prime mover's drive axle brakes and that one of the tyres on the truck's B-trailer had been sliced open.

Major defects were detected on the trucks A-trailer, with the brakes on two axles inoperative, police said.

Several work diary offences were also identified.