This afternoon I've started getting a really bad creak or groan at full steering lock (usually), both ways, and in forward and reverse. I can feel it through the steering column, and it''s easiest to replicate on when stopped on pavement, wheel hard over, then give it a little gas as if I'm pulling into a parking spot kind of aggressively. It doesn't seem to do it when just letting the engine idle moving it. It's done it a couple of times with the wheels partially turned and when driving over a bump.

All four balljoints (OEM lower, SPC upper) are 2yrs/~15k miles or less, same for ITREs and passenger OTRE. The boot was torn on the driver OTRE so I replaced it this evening thinking that might be the issue, but no.

Alignment cams don't appear to have shifted, but I'm going for an alignment tomorrow afternoon anyway. Steering rack shows no signs of moving in the bushings (poly, replaced last fall), took the swaybar off entirely this afternoon just in case that might have been it. Everything I've put a wrench on is tight.

Any ideas?

Check the points that touch when the steering is at full lock.
I haven't encountered this issue with my 4Runner... yet...but on my old '91 4WD truck which had a differently designed steering system, the steering stops(the actual contact points when the steering is at full lock) would make horrendous groaning sounds if they weren't greased or the little plastic caps had fallen off and it was metal on metal.

Same thing with my 1984 Supra years ago. Had to grease those stops now and then. Not sure what performs that function on a 4R.

have you cleaned the screen inside the pump reservoir? My 97 winter beater did the groan when I first got it. I flushed out the fluid and it was nasty, also cleaned the screen and it was totally clogged up with junk. it's not hard to clean it but it does make a mess. the pump cavitates because the screen is clogged up and it can't get enough fluid. that is my theory.

but... it did fix the groan and now my pump/racks turns like a smooth mother forker.

I can't explain the creak part, maybe ghosts?

Nope, but I need to. I don't think that's what's causing this particular issue though.

Bad power steering fluid can make really loud groans and vibrations like you're talking about. I had symptoms like yours. I flushed out the fluid and put new stuff in there and the noise and vibration thru the column went away completely. I was surprised it was just the fluid, I was expecting a lot worse.

I had almost the same problem up till a few weeks ago, but I'm kinda at a loss how I fixed it, because I didn't really touch any steering components. It wasn't a Godawful creak, but it was definitely a creak.

I replaced my driver's side UBJ (200k original with a torn boot), and I installed new Prothane front sway bar bushings. I LIBERALLY used Lucas Blue Marine grease on top of the monkey snot that Prothane provided.

I left the passenger side UBJ, but plan on doing that soon.

And now my creak is gone. Unintended side effects, and I'm confused, but I'm not complaining.

+1 for saying start with a nice fluid flush if you haven't in a while. I thought my power steering bearings were shot, but fresh fluid and its as quiet as can be now

Y'all saying to flush the PS, when you had issues could feel it through the steering column? It feels like something is moving and sounds like metal on metal.

Mine groaned when really cold, below 30 (well in texas anyway), so I had it flushed, refilled with new fluid, took care of that.

But it never was anything that could be Felt in steering column or sounded like grinding metal, it was only a groan but not load or metallic sounding. Yours may be further along in the wear? I'd still spend the few bucks on a flush/refill, may be worth it. Luck.

Metal on metal is your bump stops. Grease 'em. Super common noise on the 87-95 model years.

I put a bottle of synthetic power steering fluid from the parts store in my power steering reservoir and that took away a ton of the pump noise. Now it's almost silent at full lock.

errr... Power Steering Fluid? why not ATF?

How are your lbj?

Yup mine was very loud and could feel it thru the column. Felt like a metal to metal harmonic grind. But.......my power steering pump was getting loud to. It was I guess having trouble passing the fluid, gunked up, fighting itself when I turned the wheel. mine got progressively worse, it wasn't all of a sudden.
I just did a lazy flush, pulled the rack line, ran some fluid thru it running, closed it up ran it, flushed it again. Took under 30 minutes. Worked like a champ after that with well over 300K on all steering components. I think power steering flush is out of most peoples thoughts for maintenance.

It's power steering fluid made specifically for Asian vehicles like Toyotas. I've had poor luck with ATF in the past (leaks, rack failed, loud pump noise) so wanted to try something else. I'm really happy on how it quieted down the pump.