The hydraulic rod in the trunk of BMW 5 Series is cold.

When the weather gets cold, you will feel insensitive. Generally, it will be fine when the weather is warm. If there is oil leakage, just buy an original factory in the auto parts city and install it.

The hydraulic rod is a supporting rod. Its working principle is: in a sealed space, a high-density liquid substance is added, and then the air inside is pumped out, and a piston-like thing is added outside, so that the high-density liquid substance can generate energy when compressed.

In a certain mechanical and electronic system, the hydraulic principle relies on the static pressure of liquid medium to complete the accumulation, transmission and amplification of energy, and realize the portability, scientificity and maximization of mechanical functions. Using hydraulic principle, hydraulic transmission system and hydraulic control system can be built. The basic function of hydraulic circuit is to transfer easily controlled energy in the form of liquid pressure energy.