You might try John Deere Corn Head Grease. Good stuff for a steering box, and won't leak out like the 90 wt gear lube.
Some specs from Deere:
Special-Purpose Corn Head Grease (AN102562, AH80490, TY24428)
Applications
· Formulated for John Deere corn head and other slow-speed gear cases
· Extra-soft grade of lubricating grease, required for row-unit gear cases of John Deere corn heads
· -30 to 330°F (-34 to 165°C)
Kurt
