The Driver and Vehicle Standards Agency (DVSA) is warning fleet operators about seriously defective aftermarket truck brake drums.

The defective drums have been identified in two cases where aftermarket drums, not manufactured or supplied by Scania, failed on P400 lorries. 

Both lorries were left without front braking when the drums failed – the braking surface fractured and separated from the mounting ring – and both were fully laden.  DVSA believe this was not due to normal wear and tear.

DVSA have been unable to identify the manufacturer but have released an image of one of the failed drums (pictured) and are asking operators to get in touch if they have similar drums fitted to their lorries and their supplier. 

Scania (Great Britain) suggests that both cases highlight the need for operators to use only parts sourced from Scania. Mark Grant, services director, explained: "Our drum brake system has been developed for maximum safety with components developed as individual parts within a complex system to ensure long service life and optimum performance in a vulnerable environment.

"As part of this system, Scania brake drums have been developed for minimal wear and to counteract cracking, even in high temperatures.”

Scania says that the material in its brake drum is dimensionally stable, providing consistent performance throughout the entire service life.

Scania brake drums, shoes and linings have been designed and thoroughly tested in respect of shape, friction and heat generation, in order to prevent vibration and screeching, it added.

"Regarding brake drums available through Scania’s VRS parts programme for other marques, these are also manufactured and tested to the original equipment manufacturers standard,” continued Grant.

"As a safety-critical item, I would therefore strongly urge operators to always contact their local Scania dealer whenever the time comes to replace any component within their vehicles' braking system."

In the UK, Scania is a major supplier of trucks, buses, coaches and engines, and provides a wide range of support services through its 86-strong network of service centres. 

In 2019, Scania's share of the UK heavy truck market was 23.5% and its combined bus and coach market share amounted to 11.5%.

Operators that can contact the DVSA about the defective brake drums by calling 0117 9543425. Vehicle safety defects can also be reported at via the DVSA’s online vehicle recalls and faults service or by emailing vsb@dvsa.gov.uk.