Check rack pre-load in FSM....that's sounds classic "pre-load too tight " - go from there if not fully 'fixed'.
DIRTY / SANDY grease on drv's side (the actual RACK) may also need removal of ALL grease , then a fresh new 3/16"th inch layer of grease on rack gears as far as you can possibly reach INTO the L. side of rack (slide that boot away ya)
p.s. Hold off of buying those EXPENSIVE suspension parts on a whim or a kind of 'guess' ....for now !
Try the simple things FIRST ....like what I just said , and / or other's tricks of the trade on here.

Yep, Mac is right, but there's one other possibility if the wheel also has stiff spots 360 degrees in each direction. Then you're probably looking at a bad steering shaft u-joint.

Yes Yes , while under my J30 tackling this very kind of work or diagnostic , I ALWAYS blast WD or a good Silicone on my 'single ' steering shaft ' u-joint ( and I of late DON"T use WD much do to other chemicals are out there with better specific features) . Some steering shafts also may have two little u-joints by adding a short 'intermediate shaft in the 'mix' .
I'll have helper turn 'lock - lock' (gently @ the full stops now! ) , while I spray Liberally ( ) , then w/fluffy terry-towel give a wrap & a squeeze gets the excess - but leaves a smooth-acting u-joint.

Same with inspecting the rack teeth - clean enough ? enough grease on it ? For THAT is basis NOW to go and do your pre-load adj. JUST BE SURE TO MARK YOUR INITIAL POSITION.........TO BE ABLE TO GO BACK TO
p.s. Dont be afraid if you may like slightly looser OR slightly tighter pre-load...it's subjective to exactly what will make you comfortable with alleviating the stiffness , the CONSTANT CORRECTIONS needed , and the hysteresis ( it OVERSHOOTS and you go back a few degrees to constantly be 'on top of ability to control' ) , ............................Now ....ALL THAT IS ..........PRELOAD
reminder= grease ANY outer tie-rod ball joints , IF there