Selective Laser Sintering (SLS) is close to be accepted as a genuine production technique (Additive Manufacturing). However, one problem restricting a more frequent specific use of SLS-parts is the limited or unknown long-term or functional behaviour under particular environmental conditions. In our specific case, for automotive applications, plastic materials can get in contact with brake fluid and coolant. The behaviour of commercial SLS materials in contact with these liquids must be qualified in advance for a successful implementation. This contribution investigates the resistance of Duraform® DF and Duraform® HST SLS made parts in contact with the cited automotive media. The testes were carried out for parts as of the machine and in a post processed coated state. Distinctive Epoxy-, Silicon- and PVC-based sealant was used. Gravimetric analyses and results of mechanical behaviour are presented with respect to material, type of coating and immersion time.