The invention relates to an antivibration support to be inserted between the frame and the engine of a vehicle. The support comprises two deformable chambers filled with liquid, separated by a deformable partition, and communicating with one another through a restricted passage, namely an operating chamber whose lateral wall forms a support and joins two rigid parts fixed respectively to the frame and to the engine, and a compensating chamber. When abnormally high thrusts are applied to the engine, the deformations of the wall are limited by abutment, against a ring immersed in the operating chamber and borne by the first rigid part, of a central foot fast to the second rigid part, and passing with clearance through the ring and/or of an overlapping sole terminating this foot.