Thermoplastic vulcanizates (TPVs) are a special class of thermoplastic elastomers, in which dynamic vulcanization of the rubber phase takes place during melt mixing with a semicrystalline thermoplastic matrix phase at elevated temperature. High performance TPVs or so called “super TPVs” are a new generation of TPVs which exhibit high heat resistance as well as excellent oil resistance properties suitable for automotive under-the-hood applications. In the present work, a new Super TPV based on carboxylated acrylonitrile butadiene rubber (XNBR) and polyamide 12 (PA12) of different blend ratios has been prepared by using a fixed concentration of a novel cyclic monofunctional peroxide for initiating the dynamic vulcanization. The final morphology of TPVs varies from either a co-continuous to a dispersed one depending on the blend ratio. TPV with a wt% ratio of 50:50 XNBR-PA12 shows the highest mechanical properties as well as superior thermal stability among all other tested formulations. From differential scanning calorimetric (DSC) study, it can be clearly seen that the glass transition temperature (Tg) of XNBR has shifted to higher values in case of all TPVs as compared to that of the uncrosslinked blend system. Dynamic mechanical analysis (DMA) also demonstrates that tanδ values of all the TPVs are lower and the storage moduli are higher than the uncrosslinked blend system. The lowest tanδ peak of the TPV with a 50:50 wt% blend ratio of XNBR-PA12 indicates the highest degree of crosslinking and this is also supported by the swelling studies. Heat aging and oil resistance studies have also been carried out in details to characterize the behaviour of these high performance TPVs at service conditions. Key words: Thermoplastic vulcanizate, XNBR, PA12, Oil aging and heat aging.