This paper presents an integrated thermo-mechanical model for analyzing angular contact ball bearings (ACBBs) operating under oil-jet lubrication. The proposed approach enables a comprehensive analysis of both the mechanical and thermal behavior of the ACBB system. The proposed formulation employs a quasi-static approach to accurately calculate contact loads and heat generation, taking into careful consideration variations in internal clearance resulting from factors such as surface pressure, centrifugal forces, and thermal expansion. For the thermal analysis, a refined thermal network model is utilized. The proposed thermal model incorporates a newly derived correlation for the drag coefficient under oil-jet lubrication, which is obtained through high-fidelity computational fluid dynamics simulations. The validity of the proposed model is confirmed through comparison with experimental data. Furthermore, extensive simulations are conducted to investigate the impact of bearing fit-up and thermal variations on the performance of ACBBs.