EpikSc400

Sorry for the long post, just want to be as detailed as possible. No ego here, I always want to learn from those more experienced than myself, but I know my way around a car. I do all my own maintenance and installs, on many makes and models I've owned, outside of needing special equipment or machinery. Tie rods, coilovers, fbos, whatever. But, my GS is just a daily I want to enjoy, not a project I'm trying to chop up.

2020 GS350 F RWD.
Purchased car used from a big name non Lexus dealer at ~30k miles. Owned a 2015 GS350 F RWD before this. That car was so smooth, even after RSR downs and spacers up to the 85k I left it at.
Both cars I am 2nd owner, both were lease by 1st owner, and clean carfax. Which guarantees nothing I know.
Currently at 60k miles. (30k in less than a year?!) I know, but all highway. Still takes its toll, but nothing like city miles. Also, no big pot holes or major surface imperfections and don't have that commute anymore. At least in the last 8k miles.

'20 GS pulled Hard right. Took it back and they "aligned" it. This next part is my fault, but I worked 2hrs away from the dealer at the time. They delivered it after a few days and the "fix". Dropped off car to me with no paperwork and picked up the loaner they gave me. Again, my fault. As someone who works on their own vehicles, and is super skeptical of mechanics I should have known better. It had awful tires, but good tread, and I assumed the bad ride was due to that.

Fast forward less than a yr and a few days ago I got new tires. Testing the Gmax AS07, and want to give quality input as the AS05 always treated me more than well on my '15. The day after tire install I went to get an alignment, non Lexus dealer, small shop near me with actually amazing reviews. Shocking right?
Anyway, shop supervisor thinks this vehicle was damaged and repaired at some point and suggest a body shop verify as we couldn't see any damage or bent arms. Didn't even charge for the alignment, adjusted toe to get me driving straight at least.
From research, GS has limited adjustment capabilities outside of aftermarket.
Last place to touch this car w​​​​as dealer after "fixing" alignment (Before Measurements). Bottom is the shop after new tires.
Car is bone stock btw. Shop had Hunter rack, but honestly idk which series it was and didn't think to ask as I've never had alignment issues.

When I hit a bump or say the dip from a drain, the car gets thrown to the side momentarily. Best way I can describe it is a wiggle like jello. Like if you were driving straight and wiggled the wheel left and right really fast for a second and then it stabilized.

The new tires helped tremendously to be fair, but I still feel it and dont want to eat up the new tires.
Any and all input, ideas, or suggestions is appreciated as I'd like to keep this car.
Taking it to a Lexus dealer for alignment is my next solution , but curious if anything else stands out here.
TIA

EdgarLex

I might be missing something here but I think one wheel having .5 camber and the other 2.5 isn’t normal. Mine have a .4 difference. Yours is 2.1 🤔

I wonder if that machine was out of spec or you have adjustable arms and one isn’t set right.

Lanson

Yeah, that rear camber is weird. You know I was shopping Rock Auto and NAPA, and there is a fair proliferation of rear camber upgrades for adjustment. Maybe snag some adjustable arms and see where that gets you, preferably dead center of the desired spec.
Edit: you symptom makes sense if you're feeling it from the rear, or if your thrust angle is changing because of the abrupt toe change as the suspension cycles. The 2 degree camber difference is probably visible, if you do a comparison left to right. The side that is .5 deg neg camber may have been hit, or possibly just a really nasty pothole or something. IDK, it's a very rare car though. Like what, 1 in 200 for the year?

EpikSc400

Definitely factory arms, non adjustable. They let me look under the car, which i asked before alignment, and at first they said no due to liability, fair enough. But, I felt and knew something was off with this car. Shop supervisor was like, I can't align this car, reasons. And we looked, there's no visible damage. I know a bent suspension part and/or what a replacement looks like..But, nothing.
My best guess, previous owner went into a "slide" and hit something. Curb or whatever. That's the only thing that makes sense as there's no body damage. At least to me anyway.
The massive difference in rear camber is what throws me off.
I definitely feel like it's the camber that's causing the "wiggle".
I've had slammed cars on factory arms that never felt like this.

Thanks for the responses, I'll get some rear adjustment arms and follow up.
Just seems strange to be so far off on rear camber. A degree, okay, mileage..maybe. But, .5 to 2.5 seems drastic.
Again, no alignment expert here, but, I've done enough suspension mods that I know a factory spec car shouldn't feel like this.

GrandSedanFan

iTrader: (1)

If you suspect that the car slid into a curb, you may want to make sure the rear subframe is aligned. The rear lower control arm would transfer all of that force to the subframe and may have shifted it in relation to the body. You may also want to check for torn bushings or damaged ball joints.

EpikSc400

I'll definitely have a body shop check it out. It could have been a wheel damaged and replaced, but everything else still took the hit underneath. We did look at control arm bushings, sway bar bushings, and ball joints, none appeared to be cracked or torn. Again, doesn't mean they weren't replaced, just what we saw in real time. I'll have to look and see if original markings are still on the bolts and nuts or if there's any sign of tools being used on them.