Windshield wiper transmission

A mounting for a windshield wiper pivot shaft on a vehicle cowl panel includes a transmission having a housing defining a base surface and a tower projecting from the base surface, a bore through the tower for rotatably supporting the pivot shaft, a rectangular aperture in the cowl panel having a pivot edge, a circular aperture in the cowl panel overlapping the rectangular aperture, a lip on the housing at one end of the base surface, and protuberances on the housing on an imaginary circle having a radius corresponding to but slightly larger than the radius of the circular aperture. The transmission is mounted on the cowl panel by inserting the tower through the overlapped apertures, hooking the lip on the pivot edge, and pivoting the housing toward the cowl panel so that the protuberances engage the circular aperture in interference fit fashion to remove all clearance between the transmission and the cowl panel when the base surface abuts the cowl panel.