Donohue was able to muster fifth-place finishes at the Swedish Grand Prix and the British Grand Prix, but the new Penske PC1 chassis proved problematic, as evidenced by three retirements in the first six races.
Donohue conseguiu acadar o quinto posto no Gran Premio de Suecia e no Gran Premio do Reino Unido, pero o novo chasis de Penske PC1 resultou problemático, como o demostraron tres retiradas nas primeiras seis carreiras.