Thumping noise coming from rear passenger side?
 

Hello all. An issue I been noticing recently is that whenever I drive over any sort of bump or pothole I notice a thump coming from the trunk. I popped open the trunk and checked the spare, jack and iron and they're all snuggly fit. Researching I found some common solutions or causes like it being possibly from the seatbelts or the seats not being properly latched? Gonna try and lowering the back seats but I dont know if its related to the type of noise im hearing. I will post a video later today when I drive back home but for now the best way I can describe it is if a tennis ball was bouncing around the trunk on the rear passenger side. Even driving over tar lines or reflectors will make a sound thats different from what I hear normally going over those on my left ear/driver side

The car feels and drives fine its just kinda ruins the mood when I feel like having a silent commute. Would taking it to a dealer be worth it? What's the likelyhood of them finding the source when it comes to these things?

Edit: Forgot to mention the car has 34k miles so everything is mostly new part wise.

https://files.catbox.moe/jx8wir.mp4
Here's hoping you guys can hear it

Here's another one
https://files.catbox.moe/tje1wp.mp4

have you inspected the rear suspension while jacking the car up? specifically the spring mount

Unfortunately I don't have any real jack besides the one that comes with the spare. Idk if that will be enough to full see what's going on under there. But I'll try and get a better look when the sun is up. I recently got my alignment done at a trusted place and the mechanic didn't bring up any concerns he could have saw during it so I haven't really put much thought into the suspension since then.

Recommend you take it back to the shop you had the alignment recently done as it may be related.

Welp turns out my right back struct has completely leaked and is out of commission... you think that's the cause of the sound or just a symptom of something even more deep in the suspension.

i suspect that is your problem.

yeah, that never works for me.

we always bring the work vans to the same place. i always tell them "look over it hard, this being a company van, it's getting ridden hard, put away wet, and won't be back for anything until the next oil change or flat tire."

and then a week later we're back for a leaky shock, or a banging sway bar link...

Yeah it just makes the thing hurt more cause of the false sense of security. I'm thinking finally we are 100% and then there's something that was overlooked so another week of planning your return to the shop.

It all started like this...
I went to get an alignment done cause my ABS and TCS lights were on and got told that the front control rods are bent and need replacing so they can't do it and that was the culprit of the lights. Take it to my friend in the body shop said they can do it cheaper than the dealer but recommend this one suspension shop that can repair it without having to buy new rods. And viola. Good as new. I go home thinking all is well but then hear the problem in the thread. Dealer says strut is indeed bad and could be replaced there for your typical dealership mark up price. But it's take 4 hours or so. AT LEAST the dealer didn't mention anything about my front control rods being bent during the diagnosis. So I can hopefully rest knowing that is no longer an issue but man things just snowball.

Each separate week seems to dedicated to a problem and I know it's not that things are just falling apart cause 1. It's a toyota and 2. It's only 30k miles old with only 1 previous owner. just things that are being overlooked...and rediscovered.

1 - It's more a Subaru than a Toyota but even then there is no such thing as a bullet proof manufacturer

2 - Those 30K miles from the previous owner could have been very very hard miles. Low mileage alone does not mean a thing.

Well now that the problem has been identified I just lastly need help on how I'm gonna go about it. I found some OEM struts on ebay, used of course.

I also found what apparently is OEM recommended replacement strut.
https://www.kyb.com/products/excel-g/
But it looks different in terms of design to the stock struts even if im getting multiple confirmations that it is compatible with my 86.
downside is that it seems to be out of stock and I dont know how long id have to wait on it to get here while I drive with a busted strut.

Other concern on my mind is if having one aftermarket/replacement strut with 3 other stock struts is going to throw the feel or driving experience out of whack from what was intended when it was manufactured. Either way both will save me more than what the dealer would charge so there's that at least.