This page has specialist questions for heavy vehicle drivers regarding Class 3 and 5 heavy vehicle dimensions.
You can use these questions to test yourself, or have a friend or family member test you.
If you don’t know the answer, click on the link underneath the question to find out.
1 What is the maximum width permitted for a heavy trailer (other than an agricultural trailer) from its longitudinal centre line? _____ metres
Dimension requirements - width
2 What is the maximum distance a load may extend behind the body of a trailer before an overdimensional flag is required? _____ metres
3 What is the forward distance of a full trailer (other than a pole trailer), the front axle of which is steered by a towbar?
Heavy combination motor vehicles types - axles
4 Between which points is the forward distance of a semi-trailer measured? From the _____ to the _____
Heavy combination motor vehicle types - forward distance
5 What is the maximum distance a load may extend out from the side of the body of a trailer before an overdimensional flag is required? _____ mm
6 What is the maximum permitted forward distance of a semi-trailer? _____ metres
Heavy combination motor vehicle types - forward distance
7 For a heavy full trailer, the maximum rear overhang including its load is the lesser of: _____ metres or _____
Heavy combination motor vehicle types - rear overhang
8 What is the maximum overall length for a truck and semi-trailer combination including its load? _____ metres
Heavy combination motor vehicle types - overall length
9 What is the maximum overall length for any heavy motor vehicle towing two trailers and including their load? _____ metres
10 What class of licence is required to drive a combination vehicle that has a gross combined weight of 25,500kg? Class _____
Classes of driver licence - heavy combination vehicles
11 What is the lowest class of licence required to drive a combination vehicle that has a gross combined weight of 14,000kg? Class _____
Classes of driver licence - medium combination vehicles
12 What is the maximum height of a heavy motor vehicle from the ground?
13 What is the maximum forward distance for a heavy motor vehicle with a tow coupling? _____ metres
14 During the hours of darkness, when the load you are carrying is greater than 1 metre wide and extends from the rear of the vehicle by more than 1 metre, what warning devices are required?
