Here’s another Flint Hydraulics Tech Tip: What causes pressure in a hydraulic system? This is one of the least understood facts about hydraulics. The answer to the question is simple – resistance to flow causes pressure in a hydraulic system. Hydraulic pumps do not “pump” pressure; they create flow. When the flow from the pump encounters resistance, pressure results. Need help troubleshooting? Call our team of experienced troubleshooters today at 901-794-4884 or email email@example.com.