Conference: vehicle test results improve but recurring defects persist

Logistics UK chief of staff Michelle Gardner discussed the legislative compliance of British operators at the Transport Manager conference.

Test performance was generally improving: the final failure rate for trucks was down to 6.7 per cent from nearly 18 per cent 21 years ago. Fail rate for trailers was just 5.9 per cent: down from 8.9 per cent 10 years ago. However, the same categories of defects kept recurring over time. In descending order, these were: brake components, glass and view of the road, tyre condition, lamps, oil leaks, suspension, steering, headlamp aim, service brake performance and chassis condition.

The list for trailers was slightly different: brake components, service brake performance, suspension, chassis condition, tyre condition, park brake performance, lamps, markers and reflectors, spray suppression and wheelarches, and side and rear under-run guards and bumpers. Ms Gardner pointed out that three of the top six reasons that trailers failed were brake-related.

Operator compliance risk scores (OCRS) were an accurate predictor of test-performance: red-rated operators failed one in four of the tests they submitted vehicles to.

DVSA had inspected 27,000 targeted vehicles at the roadside. One in five got a roadside prohibition. More than one in four of vehicles that were weighed got an overweight prohibition.

Drivers’ hours compliance continued to improve; just 2.7 per cent of drivers checked got prohibitions.

ADAS systems such as lane departure warnings were now being assessed when vehicles came in for annual test: but a non-functioning ADAS system did not currently trigger a fail or impact an operator’s OCRS.

“This may change in the future,” she warned, “so include them in checks and maintenance.”

She warned operators who were called to inquiry by the traffic commissioner to take the matter very seriously.

“Most PIs result in a sanction against the operator and less than 19 per cent of appeals against a TC’s decision succeed.”

The Guide to Maintaining Roadworthiness (last updated in 2025) remained the benchmark for good practice.

“Its advice can be deviated from, but the onus is on you to show that your practice is equally effective and you must have evidence to prove this.”

Electronic brake performance monitoring was accepted instead of roller-brake testing for trailers, but it did not cover parking-brake effectiveness which had to be physically measured and recorded.

Michelle Gardner reminded operators that while they could outsource the maintenance of their vehicles, they could not outsource the responsibility for keeping them roadworthy.

She urged operators to use the Maintenance Provision Rating Scheme (MPRS) when choosing a third-party workshop.

“Not every workshop needs to be Platinum-rated,” she said, but pointed out that MPRS could support confidence in choosing a workshop, reduce the risk of poor maintenance outcomes, give clarity in matching capability to fleet requirements, and provide a basis for regular reviews with the workshop.

“Use it alongside your own maintenance contract checks, KPIs and service reviews,” she concluded.