Your questions answered

Do I have to jack the rear of a Class 5 lightweight vehicle?

Yes. Section 2.6 - Rear Suspension and Wheel Bearings applies to all vehicles other than those with a Design Gross Weight (DGW) of more than 5000kg. As the threshold for Class 5L is 5000kg, the rear axle of these vehicles must be jacked in order to assess the rear wheel bearings and more easily examine other testable items.