In summary, FEBI BILSTEIN 75W-90 GL-5 may not meet the necessary performance standards for high-load and cold-temperature applications expected of API GL-5 gear oils. The low weld load, noted at 315 kg, falls below the typical minimum of 350 kg for API GL-5 oils, indicating insufficient load-carrying capacity. This shortfall suggests that the oil may be less effective under high-pressure conditions, leading to increased wear and reduced component durability. Given these deficiencies, it is likely that this oil is more similar in performance to a GL-4 grade oil, making it potentially unsuitable for the demanding conditions commonly found in gear systems that require full GL-5 protection.