This report deals with an exam report written by Olle Hjalmarsson and Thomas Likar, students at Högskolan i Halmstad. The project was carried out for Haldex Traction AB in Landskrona whose business consist of manufacturing automatic all wheel drive systems (AWD-system). These systems consist of a plate clutch which activates all four wheels of a 4-wheel driven vehicle. An important component in these clutches is the accumulator which basically consists of a piston under the load of a spring which creates an oil pressure with the help of an electric motor used for actuating the clutch. At Haldex difficulties has been experienced regarding the assembly of the accumulator parts due to the small tolerances between the piston and the hole of t...