The gross vehicle weight of a trailer pulled by a lorry of gross vehicle weight rating over 3.5 tons must not exceed:
Show the correct answer
Correct answer
C. the gross vehicle weight of the lorry increased by 40%.
Explanation
The question is about a trailer pulled by a lorry with a maximum permissible mass over 3.5 t. The actual total mass of the trailer must not exceed the actual total mass of the lorry increased by 40% - answer C.
The Road Traffic Act states that the actual total mass of a trailer pulled by a lorry with a maximum permissible mass exceeding 3.5 t must not exceed the actual total mass of that lorry increased by 40%. What counts are the actual masses, that is with the load at that moment: if the lorry weighs 10 t, the trailer may weigh at most 14 t. A limit equal to the actual mass of the towing vehicle (answer B) applies to passenger cars, lorries up to 3.5 t and buses, and the unladen mass (answer A) applies to motorcycles and mopeds. The rule does not apply to semi-trailers. In practice you are not allowed to pull a heavily loaded trailer with an empty lorry, because a trailer much heavier than the towing vehicle would push it when braking and could jackknife the combination.
Legal basis: Art. 62 para. 1 point 2 and para. 2 of the Road Traffic Act (Prawo o ruchu drogowym)