Trailer servicing schedule & maintenance checklist

Many people don’t understand a trailer needs Servicing in a similar fashion to a car.

In our Eyes this is more important than servicing a car for the following reasons.

• Your trailer is usually used for carrying heavy weights that can cause damage or injury at speed if there is a problem
• If a trailer becomes detached or has a major problem you are not in control.
• Your car is checked yearly (during an MOT) this is not currently need on trailers.
• Vosa are beginning to check trailers more often for roadworthiness This can result in Points, fines or a trailer being Seized.

Maintenance of the trailer is down to the trailer owner, transport manager of a company.

Poor maintenance of a trailer can result in Catastrophic results. Please read NTTA Article.

Opinions differ in the times a trailer should be serviced. We recommend the minimum checks that should be done on a trailer to the schedule shown below.

Every Trip

Check

• Lights work correctly
• Coupling has no play on towball.
• Tyre pressures
• Wheel nuts (correct torque)
• Breakaway cable / Secondary Coupling chain / cable
• All fasteners (ie doors and sides) are fastened and working.
• Correct Number plate displayed
• Load is secure

500 miles from new or after major service.

• Brake adjustment
• Taper roller Bearings
• Any bolted Connections / fittings (new trailers only)

Major Service (Braked trailers)

This should be carried out

3 months / 3000 miles on commercial trailers with intensive use & boat trailers

6 months / 6000 miles on light use trailers

If you buy a used trailer

• All items under Every trip
• Check Bearings
• Remove hubs
• Inspect Brake Shoes and springs
• Inspect Drum for damage
• Brake Expander
• Brake cables
• Auto Reverse Mechanism
• Taper roller bearings clean and regrease
• Adjuster operates
• Re assemble and adjust the brakes.
• Check condition of wheels and tyres
• Check uneven wear on tyres as this can indicate axle problems
• Visual check Wheel alignment for bent axles ( this is not easy on a single axle trailer.)
• Check for Vertical play in Drawbar
• Grease coupling
• Check coupling Linkages
• Check coupling bellows
• Check coupling Damper
• Check Handbrake Operation
• Check operation of jockey wheel
• Inspect wheel on jockey wheel
• Inspect wiring for damage
• Check all body fittings are secure and operate correctly
• Check all bolted connections as these can work loose especially axles and couplings.
• Check operation of props, jacks if fitted
• General condition (bodywork, chassis for bends and cracks)

 

Major Service (Unbraked trailers)

This should be carried out

3 months / 3000 miles on commercial trailers with intensive use & boat trailers

6 months / 6000 miles on light use trailers

If you buy a used trailer

• All items under Every trip
• Check Bearings
• Taper roller bearings clean and regrease
• Check condition of wheels and tyres
• Check uneven wear on tyres as this can indicate axle problems
• Visual check Wheel alignment for bent axles ( this is not easy on a single axle trailer.)
• Grease coupling
• Check operation of jockey wheel
• Inspect wheel on jockey wheel
• Inspect wiring for damage
• Check all body fittings are secure and operate correctly
• Check all bolted connections as these can work loose especially axles and couplings.
• Check operation of props, jacks if fitted
• General condition (bodywork, chassis for bends and cracks)

If you keep to this maintainance schedule you will probably find there is very little wrong with your trailer unless the trailer is abused but if it is neglected 1 problem can lead to another and end up costing a lot of money or cause an accident.

If the trailer is left to stand it is still recomended to service the trailer as brake parts, bearings and couplings can all corrode or Seize through lack of use, tyres can perish and electricals can corrode and stop working.

A couple of problems we regularly find on trailers that don’t come for service regularly are.

Brake cables seize and due to the lack of movement the expander seizes and the brakes usually rest in an open position rubbing the brake drum that wears the Shoes and in bad circumstances they damage the drums. This also effects the brake effiency and the amount of fuel used to tow, When you really need the brakes they are not there this can cause an accident for the cost of a brake cable.

Wheel bearings failing. With wheel bearings you usually will get a bit of warning (play) before a bearing fails. When a wheel bearing fails the whole wheel usually comes off this can damage the shaft as it comes off or if the shaft hits the floor this means a new axle / suspension unit at an high cost also a trailer wheel can cause a lot of damage/ injury if it hits something or a person.