Proper axle maintenance can save money and improves safety

JOST Axle Systems was previously known as Mercedes-Benz TrailerAxleSystems. As one of the two distributors of genuine parts for legacy Mercedes-Benz systems in the UK, the company is all too well aware of the prevalence of poorly manufactured, sub-par counterfeits on the market.

With most commercial vehicle trailers serviced every 6-12 weeks depending on mileage, servicing costs are something every operator wants to keep under control. When it comes to maintenance and repair, everyone recognises the necessity of only using qualified workshops to perform the work on axle systems and associated components; understanding that improperly performed maintenance and repair work can increase costs in the long run, as well as posing a significant safety hazard.

But does this same recognition extend to the use of non-OE (non-original equipment) aftermarket parts?

Aftermarket parts that are non-OE have been found within the automotive industry for many years. Because they promise an exact-fit replacement for the OE part, it can be tempting to think that the parts must be of similar quality. Even if they are not quite as good, does that really matter if the cost savings more than mitigate any slightly shorter lifespan? After all, any wear will surely be picked up at the next service just a few weeks down the line.

During a service, the complete axle should always be inspected according to the manufacturer’s service manual: looking at brakes, hub assemblies, suspension, etc. This is where general wear and tear will be identified and parts replaced if necessary. The wear rate of different components will be dependent on the usage profile of the vehicle. For example, brake pads and discs will wear at a different rate for vehicles that spend most of their time at a constant speed on motorways than for those that are in and out of traffic on busy trunk roads.

The temptation for some fleet operators comes when looking at the cost of replacing the worn parts and comparing the price to non-OE components. However, the wear profile of a non-OE part is likely to be very different compared to a genuine OE part, and premature failure is a very real problem.

Should a premature failure occur then there will be no opportunity to identify the fault during a service, so the failure is likely to happen on the road. If it’s a brake part that fails then the consequences could be catastrophic.

Cost benefit analysis
But, this is not just a safety issue. Away from the potential hazards, while non-OE parts may be a little bit cheaper initially, there is no guarantee that they will be suitable for the job, impacting on performance, reliability and durability. Short term cost savings will almost always deliver cost-per-mile increases over the longer term.

A ‘pence per mile’ analysis on the use of OE versus non-OE parts will quickly highlight that buying lower cost aftermarket parts is a false economy. Replacement parts need to be purchased more frequently, and the workshop has to carry out more work. Further, the use of non-original parts is likely to invalidate any warranty on the vehicle and could leave the operator liable for damages in the event that a failure on the road leads to damage, injury or worse.

Reliability and durability
Commercial vehicle manufacturers are constantly developing their trailer axles, components and parts, building on the latest science and technology, to deliver the highest levels of performance in their systems. The vehicle manufacturers and OE suppliers invest millions each year in R&D and testing to ensure that the components offer the highest levels of performance and safety.

These components are designed-in from the outset, the manufacturers specify exact parameters for materials, torque values and permissible load limits. They do not, and cannot, assess replacement parts from external sources, so there is no guarantee that the aftermarket suppliers will meet the specifications for these critical parameters.

Significant deviations from the original specification are not only possible, but, in fact, likely. If you deviate from the permissible or required tightening processes and torque values, then you run significant risks to life and limb. Even the use of non-OE accessories – including non-approved tyres, rims and wheel hub covers – can increase the risk of accident. Should the worst happen, when the finger of blame is inevitably pointed, legally the driver, the maintenance manager and the fleet owner/manager all bear the burden of responsibility.

The quality of non-OE components can vary wildly. There is no way of knowing where or how a part has been manufactured, and no information on the quality of the materials used. Even if the part is of high quality, it won’t have been designed-in from the start. Using an OE part is the only way to guarantee suitability and the only way to maintain any outstanding warranty.

So how can the fleet operator ensure that he is getting approved OE replacement parts? The simple answer is to source parts directly from the manufacturer or an approved dealer. This information should usually be readily available on the manufacturer’s website, but if you can’t find it then most OE parts are supplied with QR codes or hologram stickers to indicate their OE status.

Do be careful when specifying parts and remember, just because a part says it’s suitable for a system it doesn’t make it OE approved. For example, genuine parts for legacy Mercedas-Benz axle systems are only available in the UK from JOST Axle Systems and Mercedes-Benz. There are many aftermarket parts on the market that are advertised as Mercedes-Benz Trailer Axle Systems, but, unless those parts come from one of these two companies, they are not OE parts.

The problems that can accrue from the use of non-OE parts can quickly hit the bottom line; failing time and again to deliver the performance, durability, reliability and ultimate longevity of genuine OE parts. Not only that, use of these non-OE parts can invalidate warranty and compromise safety.

The short term cost savings of using non-OE parts is almost always followed by financial pain in the longer term.