The paper presents solutions for transient mixed thermo-elastohydrodynamics of meshing differential hypoid gears of a vehicle under low speed urban driving and high speed cruising. Realistic gear meshing conditions, such as contact load including inertial effects are used, in line with engine power torque and wheel traction. This constitutes simultaneous solution of gear pair dynamics, non-Newtonian elastohydrodynamics as well as vehicle longitudinal inertial dynamics, an approach not hitherto reported in the literature. The important link between contact tribology and vehicle gearing dynamics is highlighted. It is also shown that gear teeth pairs are subjected to a starved inlet boundary condition, represented by realistic inlet flow analysis. These conditions lead to the formation of a thin lubricant film with non-Newtonian shear and with modest boundary interactions.
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