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Understand vehicle and trailer masses

Reason from the conditions, not from a memorised answer. Read the scene, choose, then open the explanation. The drawing is illustrative; the written conditions control the question.

Understand vehicle and trailer masses
Original teaching diagram linked to the source rule
1

Maximum authorised mass is a permitted rating, not today’s scale reading. For licence categories, read the relevant authorised masses in the documents rather than subtracting unused luggage capacity.

2

For the ordinary Category B light-trailer allowance, the trailer’s authorised mass is at most 750 kg. Other trailer combinations can require different entitlements; the towing vehicle must itself meet Category B conditions.

3

A licence allowance does not override the car’s towing, axle or combination limits. Check all limits, secure the load and allow for changed braking and turning behaviour.

Regulatory source ↗
Reviewed 2026-11-06

Apply the lesson · 1

Question 1 · Advanced scenarios

An ordinary B car has authorised mass 3200 kg and a light trailer 600 kg. All technical towing limits are met. Does a combined 3800 kg alone require code 96?

  1. Yes; every combination over 3500 kg needs code 96.
  2. No; the ordinary B light-trailer allowance applies here.
  3. Yes; any trailer exceeding 500 kg needs code 96.
Show the answer and explanation

Correct answer: B

Maximum authorised mass is a permitted rating, not today’s scale reading. For licence categories, read the relevant authorised masses in the documents rather than subtracting unused luggage capacity. For the ordinary Category B light-trailer allowance, the trailer’s authorised mass is at most 750 kg. Other trailer combinations can require different entitlements; the towing vehicle must itself meet Category B conditions.

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