Abstract:In order to deal with bad driving condition of dump truck and to reduce the operator’〖KG-*2〗s operational strength, in heavy truck, full hydraulic steering system has been widely used. Hydraulic system has an important impact on the performance of the steering system. According to the structural characteristics and performance characteristics of the hydraulic steering system, the analysis model of the steering hydraulic system and mechanical mechanism was built based on ADAMS, and several operating conditions were analyzed, such as steering, steering wheel angle step input, crossing barrier, etc. And under the above conditions, the response time of the steering system and the impact load of the steering mechanism in the vehicle driving process were analyzed, and the influences of the structural parameters of the system on the response time and the impact load were analyzed. The results show that the reaction time of the steering system is prolonged, and the hydraulic system can effectively buffer the impact load on the steering mechanism. Reasonable selection of the hydraulic pressure pipe geometry size between the steering wheel and the steering hydraulic system can effectively absorb the impact load.