The instant disclosure is directed to a thermoplastic vulcanizate composition comprising a dynamically-cured rubber; from about 20 to about 300 parts by weight of a thermoplastic resin per 100 parts by weight rubber and from about 30 to about 250 parts by weight additional oil per 100 parts by weight rubber; wherein the rubber comprises a multimodal polymer composition cured with a curing agent, the multimodal polymer composition comprising 45 to 75 wt% of a first polymer fraction and 25 to 55 wt % of a second polymer fraction, each comprising ethylene, a C3-C10 alpha-olefin, and a non-conjugated diene, wherein the polymer fractions have been polymerized using a Ziegler-Natta catalyst system, wherein the first polymer fraction has a Mooney viscosity of greater than or equal to about 150 ML(1+4@125° C.), and the second polymer fraction has a Mooney viscosity of about 20 ML to about 120 ML; and about 10 phr to about 50 phr of an extender oil. A method of producing the thermoplastic vulcanizate is also disclosed.