The aeolian red clay sequences of the Chinese Loess Plateau (CLP) serve as high-resolution archives of East Asian summer monsoon (EASM) dynamics from the Miocene-Pliocene, presenting key insights into global climate variability. Despite this significance, the regional- scale dynamics driving these variations remain poorly understood, hindering current modelling efforts.In this study, we reanalysed magnetic susceptibility (MS) and geochemical proxies (Rb/Sr, Al/Na, lightness) from published datasets and integrated newly calibrated records from the Shilou section to resolve regional hydroclimate drivers. We demonstrate that three interconnected mechanisms governed monsoon variability: (1) Orbital pacing: The 173-kyr obliquity cycle, modulated by Earth-Saturn resonance, directly regulated meridional insolation gradients, driving Intertropical Convergence Zone (ITCZ) migration and EASM intensity through phase-locked insolation forcing. (2) Tectonic uplift: Plateau uplift at 3.6-2.6 Ma amplified moisture transport into the Asian interior by intensifying low-pressure systems over the TP, evidenced by a 200-300% increase in dust accumulation rates (DAR) and abrupt gravel deposition at 3.7 Ma linked to L & uuml;liang Mountain uplift.(3) Pacific SST thresholds: Weakened meridional SST gradients during 5-4 Ma suppressed ITCZ convection, whereas post-4 Ma gradient strengthening enhanced ocean-atmosphere coupling, increasing monsoon precipitation as recorded in Rb/Sr and Al/Na ratios. These drivers collectively modulated atmospheric circulation patterns, with orbital rhythms pacing meridional insolation contrasts, SST gradients regulating moisture source intensity, and plateau uplift amplifying low-pressure systems to enhance inland moisture transport. Our findings establish a mechanistic framework connecting terrestrial hydroclimate variability to global climatic and tectonic processes, offering critical insights for modelling future regional hydrological responses under anthropogenic warming.