When you are removing the gear driven power steering pump from a Toyota Diesel motor to rebuild, you will need to remove the gear. The gear needs to be held in place while the nut is impacted off. Holding the gear meant two options: Put the gear in a vice (which can distort it) or use a leather glove to hold the gear. This gives a much better option overall by clamping around the entire circumference of the gear without putting to much pressure on any one gear tooth.
Definitely needed when rebuilding your old power steering pump or replacing with a new one.
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