Abstract: The present invention relates to a heat exchanger, in particular, an oil cooler for motor vehicles, constructed from trough-shaped heat exchanger plates which are stacked into one another and from turbulence inserts, having two openings for one medium and two further openings for another medium in order to form collecting ducts for the supply and discharge of the media, with flow ducts for the media being formed between the heat exchanger plates. The heat exchanger also includes flow ducts connected to the associated collecting ducts, an upper closure plate which has convexities in the region of the collecting tanks, and an intermediate plate which is provided with holes. The intermediate plate is arranged between the closure plate and the uppermost heat exchanger plate, and one of the holes, formed as a pressure equalizing opening, interacts with the upwardly aligned convexity in the closure plate to improve the internal pressure stability.