The increasing qualitative requirements of the modern diesel fuels can be satisfied by applying environmental friendly blending components and additive-packages having high performance level. The aim of our experimental work was to produce multifunctional additives based on rapeseed oil methyl ester by applying radical initiation. This process is more environmental friendly and energy economic respect to the widely used thermal synthesis method for the production of polyisobutylene (PIB)-succinimide type additives. Beside, our aim was to use raw materials originated from partly renewable source to meet the biodegradability requirements. These synthesized additives showed same or even better detergent-dispersant properties compared to the traditional PIB-succinimides and also provided corrosion inhibiting and lubricity improving effects when applied in diesel fuel, 5% biodiesel containing diesel fuel and 100% biodiesel. (C) 2008 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.