Floating-ring　bearings　are　widely　used　in　automotive　turbocharger　machinery　because　of　their　robustness,　low　cost　and　their　suitability　under　extreme　rotation　speeds.　This　type　of　bearings,　however,　can　become　a　source　of　noise　due　to　oil　whirl/whip　instability.　The　stabilizing　effect　of　lobed　bearing　shape　is　known　in　the　literature,　which　encourages　the　researchers　to　substitute　plain　cylindrical　full　floating　bearings　with　lobed　geometries　in　their　outer　and　inner　clearances　to　prevent　the　rotor-bearing　system　from　developing　oil　whirl/whip　instability　or　to　reduce　its　amplitude　of　response　when　oil　whirl/whip　instability　takes　place.　In　this　study,　a　novel　concept　of　a　floating-ring　bearing　with　three-lobed　clearances　in　its　inner　and　outer　films　is　modelled.　In　order　to　perform　transient　simulations,　a　very　time-efficient　approximate　solution　for　the　Reynolds　equation　to　the　geometry　of　three-lobed　bearings　is　presented.　Using　the　run-up　simulation　method,　the　nonlinear　dynamic　behaviours　of　a　real　turbocharger　rotor　supported　by　the　novel　concept　of　three-lobed　floating-ring　bearings　are　systematically　investigated.　The　newly　obtained　results　show　that　the　sub-synchronous　vibrations　can　be　thoroughly　suppressed　with　high　preload　factor　at　the　cost　of　a　moderate　increase　in　the　synchronous　vibrations.　Hence,　the　three-lobed　floating-ring　bearings　design　is　an　attractive　alternative　to　plain　cylindrical　floating-ring　bearings　for　automotive　turbocharger　applications.