It is critical that the hydraulic arms are FULLY lowered when unloading a load from the crossbar.
This is because, despite the clearance between the hydraulic arm and the gate (see top image), the trailer and/or flatbed may wobble when parked. This usually happens on rough surfaces, but can occur in other situations as well. So ALWAYS make sure the arms are fully lowered when parking (bottom image).
Also, always remember that the trailer’s gate must be fully raised or open so that the flatbed’s support bar doesn’t get caught on it here either. It’s the same principle as with the hydraulic arms mentioned above.
