In use all-year-round, the stock trailer has a tough life on-farm. However, a good once over each year could help its longevity and chances of staying on the right side of the law.
Alex Heath gets expert advice on how to look after your trailer.
The farm’s stock trailer is often one of the most used yet neglected bits of kit on the farm.
With a hardy exterior which encourages naivety, checks usually consist of kicking the tyres, a brief glance at the lights, and little else.
However, with a little care and regular cleaning, the lifespan of the trailer should increase and keep you on the right side of the law.
Keeping a record of the maintenance carried out, even on-farm, looks good if the worst were to happen.
Many of the points raised apply to flatbed and plant trailers also, and other brands.
To find out what needs addressing, John Barlow of Ifor Williams dealership Barlow Trailers explained what can be done in the farm workshop.
THE trailer should be serviced on an annual basis. Starting at the front, check the bolts securing the hitch assembly to the chassis.
Ensure they are tight. Occasionally, these will stretch and need replacing if this has happened.
Also, treat the ball coupling to a bit of grease on the inside, allowing for easier attachment. Check for wear inside the coupler, and that all parts are free to move.
While there, ensure the grease nipples above the trailer dampening ram are treated to a good serving to ensure the ram slides in and out easily, applying the brakes gradually.
While driving, if the trailer comes forward with a thud after braking, the dampener has failed and needs replacing. Failure to do so could result in the hitch assembly becoming worn and potentially breaking away if not remedied.
This is often because the brakes have not been regularly serviced.
Check the break away cable for any nicks, tears or rust and replace if there is any. Give the jockey wheel a touch of grease on its threads.
DAILY checks should include checking each lightbulb on the trailer is working and has not wriggled free.
Likewise, check the condition of the lenses and reflector plates, replacing if cracked or broken. Also check the condition of the plug and periodically give it a squirt of light oil for a better connection.
Tyre condition should also be monitored, particularly tread depth and side wall condition. The minimum legal depth for tread is 1.6mm.
If there is uneven wear across the tyre, it could be indicative of a bent axle.
Check the tyre pressures. Trailer tyres are designed to run at a significantly higher pressure than car tyres, with an orange sticker generally found around the front of the trailer indicating the correct pressure.
Running too low results in the trailer swaying, with tyres wearing quicker.
See the table for some of the most common tyres and required pressures found on Ifor Williams stock trailers.
TAKE the wheels off the trailer. Check the condition of the hubs and bearings, replacing any bearingsif there is any play or grinding noises.
Bearings are generally sealed for life, so do not require greasing. Take apart the brake assembly and adjust the brakes as necessary, checking the drum and pads for excessive wear.
When adjusting do not over tighten the pads as this leads to more wear than is necessary.
When reassembling and re-fitting the wheels torque them to the manufacturer’s recommended settings, found in the user manual.
One point many do not realise is the auto-reversing function of the overrun brakes is done inside the brake assembly.
As the vehicle reverses, a cam inside the assembly collapses, allowing the trailer to free wheel backwards. Ensure this is free to turn.
Often the problem of it not engaging reverse is to do with the surface being reversed on. Shingle and slippery cow yards are known to cause problems with the brakes not disengaging, as the tyres do not have enough purchase to make this happen.
The rod connecting the hitch assembly to the brakes should be just taut to the compensator beam and rockers.
From there, the four cables for twin-axle trailers or six cables for tri-axles are routed to the brake assemblies.
It is important this rod is correctly positioned to allow for responsive and even application of the brakes.
It can be adjusted by altering the nut holding it onto the gas strut at the front or on the compensator beam and rocker assembly.
Also, check the condition of the cables which are sheathed in steel and plastic. Replace if rusty, torn or the sheath has worn through from rubbing against the axles.
CHECK the suspension. Some trailers run on four rubber sausages, so check these for condition, replacing if perished.
Others use a leaf spring setup. Check the condition of the bolt and bush connecting the suspension to the chassis. If there is any play, the bushes need replacing. It is imperative to do this in a timely fashion as the bolt can shear if not dealt with.
At this point the trailer needs to be suspended in a safe manner. The alignment of the axle can slip over time, so check it is absolutely at 90-degrees to the chassis rails.
U-bolts connect the axle to the suspension. These can be loosened to square the axles up. Check each axle individually and adjust as necessary.
While the trailer is raised, check all wiring is correctly attached. Also check the condition of the floor from the underside.
It will tend to be either hard wood planks or, on newer models, aluminium planks. Check the condition of the chassis, identifying any areas that are starting to rust.
Any found should be lightly sanded and a rust proof paint applied to the area to help reduce further instances.
At the rear of the trailer, grease the hinges of the tail board. Ensure plenty is got into the sleeve of the hinge for squeak-free operation.
Adjust the springs so the tail board lifts easily when the gates are lifted.
Check the condition of the vents and their hinges, ensuring they shut properly. The hinges are now plastic. Replace if cracked or damaged.
Internally, make sure the floor is in good condition. Spray light oil on the dividing gate bolt. If fitted, ensure the decks are free to fold down easily.