Automatic slack adjusters (ASAs) maintenance guide

A guide to the maintenance and assessment of ASAs.


ASAs maintenance guide

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This guide covers the required maintenance of ASAs and how to assess their condition.

All HGVs, PSVs and trailers over 3.5 tonnes must be fitted with fully functioning ASAs.

Therefore, it’s important to be able to recognise the types of ASAs and when they should be replaced.

Published 15 July 2013