<p>Electro-hydraulic proportional valves are key control components in automobile shift systems and operate under conditions with sustained elevated temperatures. Valve sticking resulting from extremely high temperatures influences the degradation of automobile gearshift quality or even its failure. This study investigates the manufacturing methodology of electro-hydraulic proportional valves and conducts a systematic analysis of the thermal deformation dynamics and sticking mechanisms governing batch-processed valve spools under high-temperature conditions. First, a computational model is developed to quantify the deformation synergies among thermal stress fields, machining-induced residual stresses, and constraint forces under a steady-state uniform temperature field. Second, in consideration of the random occurrence of valve sticking phenomena in batch-processed spools under elevated-temperature conditions, a probabilistic sticking model is developed to quantify sticking probability, and the dimensional distribution law of valve clearance and pollutant particles is clarified. Results show that fitting clearance increases under high-temperature environments, whereas it decreases after the same material fit surface of the spool is burned during grinding, substantially increasing sticking probability. After theoretical optimization of clearance dimensions, high-temperature testing confirms the elimination of sticking events in the batch-processed valves. This study provides a valuable theoretical basis for the thermal deformation and spool sticking mechanism of slide valve pairs at high temperatures.</p>