I also use a sticky waterproof grease, something that costs a bit more is called "Dow 111" it is an extremely sticky silicone grease used for valves, and it is hard to get off even with flowing water but it does come at a price. If your rollers are like mine and wobble rollers there is no close tolerance, they are made sloppy so they can wobble to fit the hull shape so anything that will slow down or prevent corrosion is all that's needed.
