In Compression and Rebound Forces Adjustable KW Coilovers for BMW 5 Series Touring (G31) with OEM air suspension

12 October 2023

In October 2023, BMW already launched the new BMW 5 Series (G60) Sedan. Consequently, the earlier models, G30 and G31, manufactured since 2017, garnered increasing interest in the used car market. KW automotive has introduced a new coilover suspension for the BMW 5 Series Touring (G31) equipped with rear air suspension. Much like the BMW 6 Series GT (G32), this suspension manufacturer has specifically tailored the rear shock absorbers of its coilover suspension to suit vehicles with air suspension. Under the component approval process, the BMW 5 Series Touring (G31) can be lowered by 30 to 55 millimeters at both axles. Today, the KW V3 coilover suspension is available for BMW 5 Series Touring models with rear-wheel drive. Furthermore, development for the popular BMW 5 Series featuring xDrive (all-wheel drive) will start shortly. More at www.kwsuspensions.net

In the European executive car segment, the BMW 5 Series has been setting the standard for many decades. Few other model lines from German car manufacturers combine sportiness and long-distance travel comfortability. Since 1972, the BMW 5 Series has been offered and hailed as a seamless generation. With the introduction of the new BMW 5 Series (G60) in the fall of 2023, BMW is discontinuing the production of the current BMW 5 Series sedan (G30), and soon the BMW 5 Series Touring (G31) will be available. Experience shows that these two models and their predecessors will remain extremely popular in the used car market. Specifically for the BMW 5 Series Touring (G31) with its rear air suspension, suspension manufacturer KW automotive is now introducing a new coilover suspension kit. The difference from previous coilover suspension kits for older BMW 5 Series Touring models (E39, E61) with rear-leveling air suspension is that the compression and rebound adjustable KW rear shock absorber of the coilover suspension kit has been developed especially for the wagon's factory air spring.

KW Shock Absorbers Adapted for OEM Air Springs

The KW shock absorber struts, made of stainless steel, are shorter than the stock components and have been adapted for the stock air suspension's rebound travel. The original air springs are mounted onto the KW rear shock absorbers during the installation of the kit. The KW V3 coilover suspension kit for the BMW 5 Series Touring (G31) includes all necessary installation tools, and during the shock absorber manufacturing process, the KW automotive equips them with special elastomeric spring elements.

"However, things remain the same for the front shock absorber struts," says KW Brand Manager Florian Johann. "There, we were able to draw on the development of our suspension for the BMW 5 Series sedan (G30). Only the spring rate, suspension travel, and shock absorber configuration were adapted to the specific requirements of the 5 Series Touring for the front MacPherson strut." While the continuous lowering is adjusted via the threaded strut on the front suspension strut, on the rear shock absorber from KW, the original air suspension sits lower than on the stock shock absorber. Additionally, an adjustable KW link is used to set the desired lowering.

According to the component approval, the tested lowering range at both axles ranges from 30 to 55 millimeters. Furthermore, the shock absorbers can be manually fine-tuned separately for compression and rebound damping parameters. This allows for customizing the recommended setup to match one's driving preferences in terms of both driving dynamics and comfort. "This operates similarly to the optional BMW M Performance suspensions we developed in collaboration with BMW M and manufacture here at the Fichtenberg location," says Florian Johann.

The entire pre-dialed basic setup of the KW V3 coilover suspension for the BMW 5 Series Touring (G31) is always designed to be as firm as necessary and as comfortable as possible. With 16 clicks, the cross-section of the low-speed rebound valve can be reduced or enlarged. Opening the rebound valve noticeably enhances comfort. When closing the rebound valve, body roll and pitch movements are reduced, making the BMW handling even more dynamic than in stock form. Additionally, the adjustable low-speed compression can be closed or opened with twelve clicks, allowing for more significant influence over steering behavior and tire grip levels. In simple terms, the role of rebound is to connect the chassis to the road, while compression influences the compression movement and supports the body structure. The high-speed valves for compression and rebound responsible for ride comfort on rough roads or heavy impacts ensure that the BMW 5 Series Touring achieves impressive ride comfort even with maximum lowering and low-profile tires. More at www.kwsuspensions.net

Publication for free / copy requested

About KW automotive:

The KW entrepreneurial group includes the suspension manufacturer KW automotive with its brands KW suspensions, ST suspensions, ap Sportfahrwerke, as well as the SimRacing brands TrackTime and Ascher Racing. With its immense suspension portfolio, state-of-the-art production technology, and development and test center, KW successfully operates in all markets for more than 25 years. Over the past years, KW automotive has developed over 16 distinct damping technologies to fulfill its requirement of supplying "the perfect suspension for every demand".

Besides its core business, the development and production of manually and adaptively adjustable coilover kits and other suspension components for the aftermarket as well as the range of accessories of various automobile manufacturers in the premium segment, the business field of original equipment for special models and super sports cars of the automotive industry are developing tremendously positively for the German suspension manufacturer. Since KW is a development partner of sophisticated controlled suspension systems, the manufacturer disposes of the entire product portfolio of hydraulics, electronics, sensor technology, control units, and damper control systems as well as the necessary know-how for the application and tuning of complex vehicle performance systems from a single source. KW has become an indispensable part of customer motorsports throughout the past years and produces homologated racing dampers and suspensions for a constantly growing number of racing cars from several manufacturers.

Worldwide, successful racing teams rely on the patented valve technology of KW Competition suspensions. The entrepreneurial group has subsidiaries in the most significant markets, such as Belgium, Great Britain, China, Japan, Switzerland, Taiwan, and the USA. 360 employees from the 1200 employees worldwide of the Group are located at the headquarters in Fichtenberg. Software and hardware solutions are further business segments as well as events for virtual motorsports in the scope of the brand RaceRoom. Equally, the suspension manufacturers KW Damping Unit (former AL-KO Damping Unit), Belltech, and Reiger Suspension as well as the alloy wheels manufacturer BBS are brands of the KW entrepreneurial group. www.kwsuspensions.net