The present invention relates to a solventborne primer surfacer which comprises at least one additive preparable by reacting at least one alpha,omega-hydroxy-functionalized oligoester which possesses an OH number of 30 to 60 mg KOH/g, a theoretical carbon- carbon double bond content of 1 to 2.5 mmol/g, a number-average molecular weight of 1000 to 3000 g/mol, and a weight-average molecular weight of 2800 to 10 000 g/mol, and at least one alkoxysilane which possesses an OH-reactive functional group, the sum of the weight percentage fractions of all additives of the invention being 0.5 to 10 wt%, based on the total amount of the solventborne primer surfacer.The present invention further relates to a process for producing multicoat paint systems, and to multicoat paint systems producible by means of said process. The invention further relates to the use of the additive identified above in solventborne primer surfacers for improving adhesion.