Main photo: Warping of fifth wheels is a common phenomenon resulting from a combination of inadequate servicing of the coupling components, poor coupling technique and general driver abuse.    Left (inset) Damaged coupling components should never be welded or bent into shape but replaced with quality products like the Rockinger towing eye shown above.

It’s no secret that for many operators out there, the trailer plays poor cousin to the truck tractor, suffering neglect and abuse. FleetWatch asked Jost SA’s Manie Roux to outline the best way to ensure that trailers and their safety-critical components function in a manner that keeps people alive. 

FleetWatch: What safety advice can you give our readers regarding 5th wheels, landing legs and any other safety-critical items Jost supplies? 

Manie Roux: The first critical issue is correct selection. Operating procedures and road conditions play a major role in the selection of the correct product for the correct application. One product definitely does not suit all applications. 

Regular maintenance is of utmost importance. We have had instances where a sound maintenance programme made the difference between products lasting in excess of a million kms versus a mere 40 000kms when maintenance was not correctly carried out. 

Correct installation procedures will ensure that the product can be operated safely. Most OEMs do have specific guidelines for installing their products and these guidelines must not be deviated from at any cost. 

Correct operating procedures are vital. A few simple checks (taking mere seconds to conduct) could make the difference between a safe and secure coupling and a disaster waiting to happen. 

Always replace parts and components with the genuine article when carrying out maintenance. 

“Alternative” parts may be cheaper  at first glance but could prove extremely costly and dangerous in the long run. Be aware of cheap imitations and learn how to identify them from the genuine part. Alwaysensure that repairs are carried out by reputable repair centers. 

When conducting maintenance, care must be taken to thoroughly clean all components and to re-grease with the correct lubricant.  Information on the correct  lubricant can be  obtained from your OEM  supplier. 

Trainning has proved to invaluable. Most OEMs do have  training courses available on  the correct selection, maintenance and operating procedures of their ranges of products. 

By utilizing this service you ensure that you get the most out of the products and reduce your CPK costs to a minimum. 

Manie Roux, Jost SA’s sales and marketing director, points out that ongoing training of truck drivers and technicians is needed if operators are to realise extended life from coupling components.

FW: You may have some comments on various ‘unsafe/dodgy’ practices regarding trailer coupling/maintenance etc? 

MR: Indeed! We witness many unsafe practices regarding fifth wheels like the straightening of the top plate by means of bending in a bend press. Once the top plate of the fifth wheel has deformed beyond a safe limit of 2mm, it has become unsafe and is to be replaced without delay. There’s the so-called “reconditioning” of the fifth wheel by welding up the top plate and re-machining. This is an extremely dangerous practice and could result in the total failure of the fifth wheel top plate under load. It is extremely risky to use non-genuine or non-branded replacement parts when carrying out repairs. Ensure that all replacement parts are sourced from reputable sources. 

The use of wear discs between the fifth wheel top plate and the semi-trailer rubbing (skid) plate is also unsafe. This could have serious consequences and could result in mis-couplings, causing extensive damage and possibly loss of life. With the wear disc in place the condition of the semi-trailer rubbing plate cannot be determined. 

Many drivers are not ensuring that the fifth wheel has coupled positively. Three visual checks must be conducted after each and every coupling. The operating handle of the fifth wheel must have entered fully into the body of the fifth wheel. The safety latch must have dropped down in front of the operating handle, and there must be no gap visible between the fifth wheel top plate and semi-trailer rubbing plate. 

FW: What about unsafe practices regarding kingpins?

MR: An extremely dangerous practice is turning the kingpin through 90 degrees when worn down below the allowable limit in the direction of travel. This could result in kingpin failure with serious consequences. Buying kingpins that are not clearly marked with the manufacturer’s details or material batch number is also dangerous. Kingpins are often manufactured by unscrupulous suppliers from inferior materials and, with no manufacturer’s details on the kingpin, the kingpins cannot be traced back to the source. 

Regular dimensional checks must be conducted on kingpins and the fifth wheel locking mechanism. Should the fifth wheel not be adjusted for play between these components it will result in constant movement between fifth wheel and semi-trailer rubbing plate and cause accelerated wear on the fifth wheel top plate. 

FW: What about tow hitches? 

MR: Forcing the handle by means of a pipe (or similar extension) fitted over the operating lever occurs frequently. 

When it is not possible to lift the lever by hand, it is an indication that the coupling pin is “pinching” in the towing eye, typically resulting from parking on uneven terrain. Never force the lever but rather move the combination to a terrain that is level and attempt the un-coupling procedure again. 

Trailer mechanics often attempt to straighten the towing eye by bending it in a bend press. Once the towing eye is deformed or bent, it must be replaced without delay as it will be unsafe to use. Welding-in of the towing eye bush is another dangerous practice. Welding in the area of the eye will result in the material becoming brittle and could result in a fracture of the towing eye with disastrous results. 

All too often it occurs that the coupling pin has not been securely locked into its position in the towing eye. The tow hitch has a lock indicator. When this indicator is in the “out” position the coupling pin is not securely locked. A visual check must be conducted each and every time after coupling.