I read the Penrite Web site recommendation for steering gear boxes, to include vintage and classic cars, and it specifies a grease with the same rating (0) and qualities as John Deere Corn Head grease. I was particularly interested in the grease, because the oil in my BN7 steering box unexpectedly leaked out on the garage floor. Using my Might Vac, I pumped out the remaining oil, purchased a grease gun tube of Deere's product for about $6, let the tube sit in the sun a bit, loaded it into my grease gun, and pumped the steering box full. I have checked it several times since doing this, and the level remains undiminished. The steering feels just fine, and the grease doesn't leak out