This.
I always kept the ball greased on the Patrol/horse towing vehicle and at the time there was 6km of dirt before hitting the bitumen.
That car used to clock up 5,000km in 3 weeks towing and keeping the ball greased just kept things quiet and smooth.
The ex FIL used to use the sane grinding paste argument for not servicing the cattle crush, but as I was the one using it I always greased and oiled it, it just made my life easier when putting near 300 head through the yards.
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