The Quaternary aeolian deposits in the Sichuan Basin consist of three stratigraphic units. With the increasing depth, they are the Chengdu clay, brown clay, and red clay. The differences in the pedogenic features of these clays and the sensitivity of the weathering indices of the paleo-aeolian sediments to the present environment remain unclear. Based on the weathering indices of the particle size distribution, mineralogical composition, and element geochemistry, we investigated the pedogenic features of the three clay layers and some modern soils in the Sichuan Basin in China. Based on the results, the Chengdu clay and the underlying clays have all experienced more than moderate weathering, and the intensity of the weathering decreased from the red clay to the Chengdu clay to the brown clay, indicating a climatic evolution from hot and wet to cold and dry to warm and wet since the mid-Pleistocene in the Sichuan Basin. Compared with the underlying parent materials, the modern soils have lower weathering index values (SiO₂/(Al₂O₃+FeO₃) and SiO₂/Al₂O₃) and higher Rb/Sr ratios. Although the grain size compositions, chemical index of alteration (CIA), (K₂O+Na₂O)/Al₂O₃, and rare earth element (REE) signatures of the paleo-aeolian sediments remained unchanged under the present conditions, the pedogenic index values of the paleo-aeolian sediment outcrops exhibited a varied sensitivity to the present environment. Therefore, the unchanged indices may be more suitable for estimating the paleoenvironment when using exhumed and relict paleosols.