11/9/16 / LuK
So why do some garages still insist on converting the originally fitted technology to something that just wasn’t designed to do what the vehicle manufacturer intended?
To supply your customers with the best solution for their specific needs, it helps to have a good understanding of the technical differences between the products available – and most importantly – why the vehicle was originally fitted with a DMF.
The reason they are so popular is simple. Vehicle manufacturers (VMs) are not only constantly striving to meet ever tighter government emissions targets, but also to satisfy vehicle driver aspirations for improved refinement from ever more powerful vehicles.
After many years of throwing emissions hardware at today’s engines, such as Common Rail, GDI, catalytic converters, DPF etc. etc., there is still only so much you can do to an internal combustion engine to reduce emissions. It is now more common for VMs to take weight out of the car and include smaller, lighter engines that produce high levels of torque at lower engine speeds.
The Ford EcoBoost engine is a good example; it produces a peak torque of up to 200Nm at 1400 RPM from a 1.0L engine!
The latest ultra-light seven or eight speed gearboxes are also contributing to the rise of the DMF. Weight used to be the major vibration absorber – adding a weight (a mass damper) to a vibrating gear mechanism arm and you transform it from a poor quality flimsy gear change to something a BMW driver would be happy with.
The big BUT is that the more weight you carry leads to an increase in both fuel consumption and emissions levels. All of these weight saving measures, such as the smaller, lighter engines and gearboxes, down-speeding and the engine running slower (to reduce friction) simply result in an increase in vibration levels and hence the need for a different technology.
DMF is that technology, allowing VMs to achieve all of these goals. To satisfy demand, the three largest OE clutch suppliers (LuK, Valeo and ZF) all design and produce versions of the DMF for original fitment and, since 1985, the DMF has been the go-to solution for pretty much every manufacturer building vehicles today.
Later DMF designs incorporate additional springing to add further absorption capacity, and the newest versions borrow advanced aircraft engine technology – specifically in the form of the Centrifugal Pendulum Absorber (CPA). First used in the emissions busting BMW ‘Efficient Dynamics’ engines, CPA equipped DMFs are now also used by VAG in low emission variants such as the Volkswagen Passat, Audi A5, Seat Leon and Skoda Superb. Despite its miraculous vibration absorbing qualities the DMF is still basically a component and, just like any other component, it will eventually wear out.