If you tow a trailer or caravan on a fairly regular basis, then you may have become used to its idiosyncrasies and know exactly what to expect whenever you take to the open road. In short, you understand how your rig will behave in a variety of different circumstances and, crucially, what to expect when you apply the brakes. Of course, it takes a great deal more effort to decelerate a loaded trailer or caravan, but you should nevertheless expect smooth and consistent operation. If you find that the rig tends to push your tow vehicle these days or may exhibit some unusual behaviour, then what could be going wrong and what do you need to look at?
You may not know, but there is a special device contained within the coupling mechanism that helps to contain the most violent reaction when you apply your foot on the brakes. Without this damping device, the full weight of the trailer could suddenly press forward and cause an unwanted reaction. These days, you may find that the brakes begin to catch whenever you apply some pressure, and this could be due to a deficient coupling damper and/or faulty trailer brake.
Shoes and Drums
To begin with, you should have a closer look at the brake shoes and the condition of the drums. From time to time these shoes will need to be replaced, but you may find that an adjustment here or there could do the trick. Badly adjusted brakes can sometimes mimic the effects of a failed coupling damper.
The damper itself is assembled within the coupling mechanism and is carefully pressurised in order for it to work correctly. It may be difficult for you to check its operation when the rig is coupled, as it will require a lot of pressure to reset. Unload your trailer as much as possible, but you should be wary if you find that you can push the damper back to its original setting quite easily. This may indicate that the component has worn to such an extent that it is not capable of providing the correct amount of resistance.
To be confident, you should take your rig in to a trailer repair specialist for their advice. They will have the tools necessary to check the efficiency of the coupling damper and replace it if necessary. They will also offer trailer servicing for your brakes so that your rig is once again fully fit for the road.