The vacation season is a grueling endurance test for most cars: Long journeys with maximum payload, high temperatures, traffic jams, mountain passes, and poor road conditions. Maintenance shortcomings may then result in the vacation trip being curtailed early, with the vehicle stranded in the breakdown lane due to a lit warning lamp. Faulty chassis components can also have far worse consequences: In critical situations they make even modern cars with assistance systems virtually uncontrollable, particularly with maximum payload. The experts from ZF Services therefore recommend that workshops point out to owners of vehicles with high mileage in particular the importance of regularly checking the key chassis components.
Faulty shock absorbers can increase the risk of accident given the direct link between the condition of the shock absorbers and the stopping distance, cornering behavior, and the effectiveness of ABS and ESP. The performance required of a shock absorber is virtually unimaginable: With a mileage of 120 000 kilometers, the piston rod will have been moved up and down around sixty million times. The service life of the hard-working unit depends on many factors. Poor road conditions, high load, sporty driving style, cold, heat, dust, water, and salt can accelerate shock absorber wear. Current estimates assume that around 15 percent of German passenger cars are currently on the road with worn or defective shock absorbers.
The experts from ZF Services therefore recommend checking the functionality of shock absorbers and related components no later than with 80 000 kilometers on the clock and then every 20 000 kilometers thereafter – or after a period of five to six years. All of which constitutes interesting potential for independent workshops in particular since vehicles of this profile tend to make increasingly less use of branded workshops as the vehicle gets older and the mileage higher.
Safety – top priority with the steering
Steering and shock absorber wear are also closely related: Faulty shock absorbers are often the cause of premature wear on tie-rod ends or other chassis components. The key chassis and steering components must also be checked before setting off on vacation, in the experts' opinion. In this way, components such as tie rods keep the car safely on the road and can reduce premature tire wear. Where the tie rod and other chassis and steering components or the incorporated ball joints are damaged, precise steering and safe handling cannot be guaranteed.
Damage and wear may pose a serious safety risk particularly when travelling on vacation. The high payload – often associated with an unfavorable distribution of the center of gravity as a result of roof racks or bicycles on the trailer hitch – makes the car much more instable than usual from a physical perspective. In critical situations such as emergency braking or evasive maneuvers, worn components have a much more dramatic effect. The stopping distance increases, aquaplaning occurs much earlier on a wet road, and even an electronic stability program is often no longer able to prevent the vehicle from breaking out.
The importance of a professional check and parts in OEM quality
The effect of components such as shock absorbers or steering components tends to fade slowly and continually, and as such the familiarization effect is often sufficient to prevent drivers from noticing the wear themselves. A thorough check by the workshop professional can therefore prevent high consequential costs and thus promote customer retention.
ZF Services experts advise using products with OEM quality, such as Sachs shock absorbers and Lemförder chassis and steering components, which are tailored exactly to the respective vehicle. Thus, nothing will prevent you from getting to your vacation destination safely.
ZF Services has produced a video for workshops; the video illustrates clearly what a professional vacation check entails and can be downloaded here.