When fill the steering gear box use only standard GL-4 hypoid type gear oil, SAE 80W or SAE 80W/90.
See Figure 1
Check the level of the lubricant in the steering gear every 15,000 miles or 12 months. If the level is low, check for leakage. Any oily film is not considered a leak; solid grease must be present. The lubricant is added and checked through the filler plug hole in the top of the steering gearbox.