Trailer suspension does more than smooth out a ride between the trailer and the tow vehicle. It does keep the trailer stable as well, which protects your load while reducing contact with road surfaces – thus giving less wear to tyres and bearings and increased life for the frame. Knowing the requirements helps you identify issues sooner and to select a setup that suits your deployment.
Springs: carrying the weight
Leaf springs or rubber torsion units are used in most of the trailers.
Utility and plant trailers are often fitted with leaf springs. Brilliant for carrying heavy loads easily, they are hard-wearing and economical. They can sag, crack or seize over time, damaging ride height and stability.
Rubber torsion suspensions are usually seen on smaller or more specialised trailers. Provides a more seamless ride, and there are fewer moving parts, but when it goes out, it’s typically replaced as an entire unit. For Trailer Parts, visit autoandtrailer.com
Springs are rated to best suit the rating of trailer axles and their common load. A suspension that is too stiff may cause bouncing when lightly loaded with a trailer. Too soft, and it can bottom out or roll.
Dampers: controlling bounce
Other trailers also have dampeners (shock absorbers). Remember, dampers do not hold weight; they resist motion. They help ease bounces over bumps, keep the tyre in better road contact and combat “porpoising” (the up-and-down pitching sensation). The experience while towing can be unsettled if the dampers are leaking or not functioning properly.
Load handling: why balance matters
Good suspension is no remedy for bad loading. Get the nose weight right, keep heavy items low and from the centre to reduce any whirl around, followed by holding it well in place. Springs and tyres can be overstrained or unevenly loaded, which leads to stability problems.
