Did you know that a vehicle that is equipped with a standard air suspension can be lowered using individual coupling rods? Over 90% of all cars with factory Airmatic chassis can be lowered for a slim course and with minimal effort. Often these vehicles can also be lowered by changing the control part for the air suspension, but in most cases this variant rarely allows a lowering of more than 10-15 mm or you need a new control part for an often high three-digit or even four-digit amount. We would like to explain the variant with the coupling rods to you but point them out insistentlythat we assume no liability for the correctness. We do not guarantee the topicality, correctness, completeness or quality of the information provided. Liability claims against us, which refer to damages, defects of a material or immaterial nature which arise or have arisen due to the use of the information in this report, are generally excluded to the fullest extent possible.
⚠ Update 2019: qualitatively, unfortunately, underground ➡ click
So in good German: SEid you are not sure, please seek the nearest specialist workshop and let you once again advise in detail and possibly the coupling rods (pendulum supports) there obstruct the same!
Our test vehicle is an 2008er VW Phaeton GP01 which has a standard Airmatic air suspension. Alternatively, this vehicle can be lowered by approx. 15 mm using VCDS or you can use a module like this KW DLC lowering module that allows lowering by a maximum of 30 mm at the front and rear at the push of a button. But we wanted to spend a few millimeters more on the one hand and significantly less on the other. So we opted for coupling rods from the tuner BBM Motorsport at a price of € 99. As a lowering set, the rods enable the body to be lowered on the front axle by up to 70 mm and the rear axle can even drop as much as 80 mm if desired. Since the VW Phaeton is factory-set from a speed of 140 km / h a further 15 mm at the front and rear, you should of course pay close attention to this because the risk of owning an "inoperable" vehicle increases significantly.
the VW Phaeton "must" be on high level or in jack mode before it is lifted
If the vehicle is on a lift it may be possible to change the bars without removing the wheels. The rods are screwed at the top of the level sensor for the Airmatic (10er key width) and at the other end in a ball head clicked. The assembly instructions from BBM Motorsport indicate that only the upper screw has to be loosened and the coupling rod can then be clicked out of the ball head bolted down. That's correct so far, but we decided to also expand the ball head as this, as BBM correctly mentioned on its website, is often very dirty and sometimes heavily worn. If you have removed the ball head, it is much easier to clean it with a wire brush and on the other hand, you can attach directly the modified coupling rod including its locking split and check for correct fit.
250.000 km leave tracks
Our ball head at the front was also quite "worn out", which is not really surprising considering the 250.000 km mileage. If necessary, you should think about it when the modified coupling rod is clipped on and despite the split pin you have a lot of play to order a new part from your friendly VW dealer. IMPORTANT! It is very likely that you planned to lower the vehicle by more than 10-15 mm and so it is essential that you loosen ALL of the load-bearing links of the chassis and tighten them again after installing them in a "lower" position. If you do not pay attention to this, it can be assumed that all chassis components may soon quit their service and high repair costs await you.
Adjusting the coupling rods
This is an approximate indication. If you shorten the front coupling rods by approx. 10 mm, the vehicle should lower by 30-40 mm. On the rear axle, 5 mm means roughly the same difference. We decided to adjust the coupling rod at the front by 12 mm and the rear axle by 7 mm. The lowering should result in approx. 45-50 mm on the front axle and the same on the rear axle. BBM recommends installing the coupling rods to the same length as the standard rods and only when this has been done, lowering the vehicle evenly by shortening the rods. We measured the standard rods precisely using a caliper (from hole center to the middle of the threaded rod) and set all four coupling rods to the desired level prior to installation by subtracting 12 mm from the measurement result at the front and 7 mm at the rear.
⚠ current pictures from 02.03.2018 ➡ click
The installation is then carried out in reverse and on the front axle you should first screw the ball head back on (if you have loosened it) and then attach the other end of the coupling rod to the sensor. You should also try to clean the ball head on the rear axle so that the modified coupling rod has a secure hold. Make sure that the coupling rods on both the front and rear axles sit completely on the ball heads. If this is not the case, you can 100% assume that you will receive an error message and your vehicle may be completely crooked.
Are the rods installed and the nuts correctly countered you can leave the vehicle from the lift or possibly from the jack and you put in the vehicle and at closed doors start the engine. It is best to let it run for a few seconds and only then should you switch the jack mode or the high level to the normal level. The vehicle now goes much deeper than before and if everything is set correctly there is of course no difference left or right. If necessary, you should measure this from the center of the hub of the rim to the fender and, if necessary, adjust it on the coupling rod concerned. As already mentioned above, at the latest now, if everything is set correctly and the vehicle is in the low position, you should release all important suspension components on a lift and then tighten again. Only then can you prevent consequential damage.
And of course you should, as already mentioned, make sure that the vehicle lowers a bit at higher speeds (That's the case with the VW Phaeton) and when installing the coupling rods consider this further lowering. Alternatively, you should look whether possibly by means of coding this automated lowering can be disabled.
in the video 20 inch rims and with H & R wheel spacers
the front axle
the rear axle
Important NOTE! Please check that you have a parts certificate included with the coupling rods or you will try in any case for a single approval and the resulting registration the registration of the vehicle! Does that not invalidate the operating permit.
We have no specific information about the legal assessment if you install the coupling rods as "spare parts" in their original length. In this case, an entry in the papers should not be necessary, but then of course there is no lowering. Please inquire about this. So far so good! But what if the steering wheel vibrates suddenly when accelerating or braking? What if the whole vehicle shakes and you have no idea where the imbalance is coming from? Then maybe our contribution on the topic "Car vibrates or wobbles while driving - why?"!
We still have many thousands more tuning reports on tuningblog.eu, if you wanted to see an excerpt then just click HERE. And there are still a lot of test reports from us. Below is a small excerpt:
News from 02.03.2018
A few new pictures that show our VW Phaeton a few millimeters lower after we have changed the coupling rods a little bit. But this is definitely "the highest of feelings" and now all that's missing is a chic set of wheels that we will definitely report on in the near future.
A good 1 1/2 years later it turns out that the quality of the accessory coupling rods is anything but satisfactory. After about 25.000 km there is only a lump of rust left. We wanted to change the height of the vehicle a little and therefore adjust the coupling rods again. When looking “under” the vehicle, it was immediately apparent that these coupling rods could only be adjusted with a lot of luck. And they could not be detached from the ball heads, so that we have the coupling rods inklusive Brackets (fortunately possible with the VW Phaeton) have expanded. Then everything sprayed with plenty of rust remover and wait. Three of the 4 poles let themselves be persuaded, with a bit of force and tact, to be put off again. Rod number 4 has turned off immediately and dissolved in air. So here was a replacement. For a later adjustment, the rods, in our opinion, absolutely unsuitable and to what extent they continue, because of the rusted heads, their Dienstverrichten is also questionable. Of course, the installation was freshly oiled and greased but certainly not in the long run.
So far so good! But what if the steering wheel vibrates suddenly when accelerating or braking? What if the whole vehicle shakes and you have no idea where the imbalance is coming from? Then maybe our contribution on the topic "Car vibrates or wobbles while driving - why?"!
"Tuningblog.eu" - on the subject of car tuning and car styling, we keep you up to date with our tuning magazine and present you every day the latest tuned vehicles from all over the world.
It's best to subscribe to ours Feed and will automatically be informed as soon as there is something new for this post, and of course also to all other contributions.