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The following are landing gear pictures from the cobbler's hell! As a workshop that has been active for many years, you think you've seen everything. But practice is always good for a few surprises. The BILSTEIN Academy once did a lot of detailed work to research extreme damage and improvisations that made even experienced mechanics' jaws drop.
Drive shaft kills shock absorber tube
The first well-documented story is about a VW T4. One day, its owner noticed a thumping noise that could be heard when braking and accelerating. The driving behavior, however, is normal. When the vehicle was subsequently checked in the workshop, it was found that the drive shafts had worn through the shock absorber tube. The cause was a previous clutch replacement in another workshop, in the course of which the transmission/engine mounting was not properly fastened. This was now immediately done by the other company and a new BILSTEIN damper was installed. Problem solved.
Double feature with an uncertain outcome
With the shock absorber shown in the picture, the installer meant well and additionally installed the standard pressure stop. What was apparently not known: With the upside-down design, the appropriate pressure stop is already mounted on the piston rod in the shock absorber tube upon delivery. But even if that hadn't been the case: This approach is wrong anyway! The old pressure stop was simply not designed for the new damper and would have had to be replaced with a compatible component. However, this can result in extremely "creepy" and possibly even dangerous driving behavior. Our recommendation therefore: Remove the old pressure stop as soon as possible.
One turn shortened!
Why should you take the money out of your pocket for lowering springs when two cheap metal clamps will do the trick? With their help, in this obscure example, two turns were simply "stacked together". BILSTEIN saw this vehicle in person a few years ago in its own workshop. Of course, the colleagues there were only witnesses and not the cause of this dangerous improvisation, which had been camouflaged more badly than well with underbody protection. This is not only inadmissible, but also extremely dangerous. After all, this intervention changes the characteristics of the springs – and thus the handling – in an unpredictable way. Anyone who tampers with suspension springs without qualifications and appropriate safety measures also puts their lives in danger. After all, a lot of energy is stored in the windings, which is suddenly released if you do something wrong. The following therefore applies: Remove old parts and replace them with correct lowering springs. However, optimal driving behavior can only be achieved with a complete chassis with suitable high-performance dampers – such as the BILSTEIN B12.
"Frankenstein's" shock mount
If there is a fatigue fracture in a shock absorber bracket, it should of course be repaired immediately. However, this picture, which BILSTEIN was given to BILSTEIN by a trainee, shows a patchwork that would have done Professor Frankenstein credit. Since you probably didn't really trust your own welding skills, a screw was "fried" on the side for reinforcement. This repair was carried out in its entirety in a very unprofessional manner, so that the decommissioning would have been due at the latest after the next main inspection. In addition, the execution represents a significant security risk. The correct procedure would now be to replace all affected components immediately. This also applies to the shock absorber, since damage cannot be ruled out.
All that remained was a "bloodless" shell
In this case, there was extreme noise when compressing and rebounding: the support bearing had broken. However, this turned out to be only consequential damage, while the real catastrophe had happened one floor below. Due to extreme wear, the shock absorber had "dried out" completely and was no longer effective due to a lack of oil. As a result, he was no longer able to control the vibrations of the suspension springs and repeatedly went into the cable stop, which ultimately led to the bursting of the support bearing. However, this is just one of many examples of the consequential damage that a defective shock absorber can cause. The chain of possible defects can go as far as the tires. BILSTEIN therefore recommends checking the effectiveness of the shock absorbers regularly and every 20.000 kilometers at the latest. Because the spectrum of possible complications is large.
Unfortunately, that didn't go well
This photo was made available to BILSTEIN by a trainee who works for a testing organization. There, a new complete chassis should be entered in the vehicle documents. Small note: If only the shock absorbers are exchanged for those with identical functional dimensions, this is not necessary, unlike in the case of the combination with lowering springs. Even at first glance, a serious assembly error is clear in this case, which only had no consequences thanks to a lot of luck: the screw does not go through the eye of the shock absorber as intended, but past it. After all, it was so effectively clamped in the axle carrier that nothing further happened for the time being. Unfortunately, it is no longer possible to determine whether a lack of technical understanding or naive carelessness led to this outrageous fastening method. The fact is: The chassis had to be reinstalled correctly according to the manufacturer's specifications as soon as possible. After that, of course, all attachment points and compliance with the legal requirements should be checked again. Better safe than sorry!
The Long Danger
This shock absorber was sent to the BILSTEIN Customer Special Requests (KSW) department to have it customized. Unfortunately, this was not the first modification: the piston rod had previously been lengthened in a do-it-yourself manner by welding on a pin. This procedure is of course inadmissible, but also completely unnecessary. Because BILSTEIN has countless piston rod variants "in stock" thanks to its internal modular system and can even expertly manufacture them to measure if required. With far-reaching interventions like this, the shock absorber is of course completely dismantled and checked: Just put something on it outside? A strange idea for the professional. Our tip: Anyone who would like to have their shock absorbers individually modified should contact an official BILSTEIN Technical Center or Service Center directly or contact the special customer requests department at the BILSTEIN headquarters in Ennepetal: E-mail address: ksw@bilstein.de. Picture credits & text: ThyssenKrupp Bilstein GmbH
The following note is essential: For safety reasons, tuningblog recommends all repair, inspection and maintenance work exclusively to be carried out in a specialist workshop! Although our information is summarized to the best of our knowledge and belief, we cannot assume any liability for the content. All information is therefore "without guarantee".
Of course, that wasn't the end of it!
In this tuningblog category there are guides and instructions for common defects/repairs on the vehicle and for installing accessories/tuning parts. Our articles explain in a simple way common defects and the corresponding repairs and they also explain how the first signs of a defect become noticeable. In most cases, we also have initial clues to the repair instructions in our repair instructions approximate costs listed. The goal of ourAuto Repair Guide“ is to create a head start in knowledge for the next visit to the workshop with initial tips. This may save you from tedious troubleshooting and you may even be able to do small things yourself. The same applies, of course, to the installation of accessories/tuning parts. Here, too, we would like to help with the implementation with instructions and tips. There are many other posts on this as well. Below is an excerpt of the last and HERE there are all previous instructions.
