I have a 4710 and I just re-did the front suspension links this summer, have the parts on hand to do the rear when I have a little time. It was easier than I feared, hard part is getting the old bushings out. I ended up using an air hammer("muffler gun") pushing on a bushing driver. Buzzed them right out, buzzed the new ones in.

There is no more or less pressure on the linkages on the ground or in the air, but the tire will turn more freely if it's not on the ground.

I didn't do anything extra for greasing, my plan is to slop some oil on them periodically and hope it creeps in to do some good.