All HGVs, PSVs and trailers over 3.5 tonnes must be fitted with fully functioning automatic slack adjusters.
Any fitting, maintenance, or assessment should be carried out only by suitably trained and competent technicians. If in any doubt you should refer to the component manufacturer for more information. It’s particularly important to follow manufacturer’s instructions during the installation process.
This guide tells you how to maintain automatic slack adjusters and how to assess their condition.