Since 2009 Porsche has outfitted a number of their models with a dual-clutch transmission known as the Porsche Doppel Kupplungs, more commonly known as PDK. The PDK transmission offers a quicker and more direct gear change than you could have in a traditional automatic or manual transmission. This is thanks to the addition of a second clutch that handles the engagement of half of the transmission’s gear set. This new design allows for the next gear to be ready for use anytime at the press of a paddle and engage seamlessly. PDK flush is simply a replacement of your old fluid with the new along with PDK oil pan and filter.