Flaps;

Welcome to the 1800 world!

George pretty much covered it...high steering effort at low speed is totally typical even if ball joints are perfect, the OE 70 Series tires of the ES don't help, I hope you're not steeing while stopped... but even when parking, dead slow rolling of the tires will make a big difference...and sure, the steering box needs to be lubed, but with the mechanical advantage you have over it, even if bone dry it wouldn't really contribute to the high steering effort...wear out soon, sure, but not really make much diff in steering effort...I recommend you keep you tire pumped right up there (lowers rolling resistance, body roll - of which the ES has gobs(!), and improves grip in general too) check your front end componentry, alignment, and make sure you never steer without some rolling action.

I'm sure is a rule about NOT applying sidways force on a nosewheel when towing a plane with a tractor hooked up to the nosegear. Right? Same applies here! Of course, a nosewheels pivots pretty well, but you get the idea.

Cheers