Clunking and Thumping sound when hitting bumps

Hey everybody. About a week ago I went mudding with my buddy in my 2003 toyota prerunner V6, and near the end when I hit a small bump going slow crawling uphill and I noticed this "Clunk" or a "thump". He mentioned it and I passed it off saying it was probably a rock under the skid plate, later in the day I was pulling into a mcdonalds and it had a decent little lip to get into the parking lot. And I heard that same distinct "thunk" or "clunk". I parked and went to take a look at it, and there was nothing that seemed out of the ordinary for a week after that I didn't do any offroading, besides slowly driving the dirt road up to my work, and I didn't hear anything. Yesterday, I had to pick up my little sister from school, and I took a backroad back to my house. One that I am very familiar with, normally before the noise started my truck would eat up every bump without the sound going at least 35. This time I was doing 15, and it was clunking and thunking to all hell. Still drove smooth and overall had zero change in how it drove. Got back on the road and it did no such thing. Of that week of silence I attempted to recreate the sound and get it on video, but was not successful. I attempted to flex it out, nothing, I got in the bed and bounced it a lot, nothing. Nothing I did could make the sound. Yesterday I could not get a video of it because the backroad had a lot of mud, and I needed my full attention on not sliding into a Ditch. Today however, I finally managed to get a video of it making the noise on a somewhat bumpy little shortcut on my way home from work. The bunks weren't that bad but enough that I could recreate the sound. My windbreakers kind of loud, but if you turn up the volume you will hear a distinct "thunk" like a second into the video, and then two or three other identical sounds for the rest of it. https://youtube.com/shorts/GhuTmZIJN0E?si=hOP7kcDfzrA51Pg8
Every time it made the sound I could feel it in the floor. From what I have researched it could be a number of things. I've looked at my sway bar bushing and they don't that great, but they don't look bad enough to make that sound. And if they really are that bad then they must have just started to go out if the only thing that makes it is some decent sized bumps. I also looked at the driveshaft carrier bearing. And it wiggles around but it doesn't seem to be an excessive amount of play. I haven't jacked up the truck yet, but all of the front end components seem pretty right. I've heard things about cab bushing going bad or coming loose, but all of them seem pretty decent. I'll probably check again anyway, they are not my upper ball joints because I have camburg uniball uppers. And the lower ball joints were replaced not too long ago. I'll try jacking it up tomorrow to see what's going on, but if you have had the same sound and might know what it is, please let me know! my passenger side sway bar bushing my driver side sway bar bushing, I'll update with more photos when I look at it more.

 

Check your ubolts, CSB, and DS bolts/nuts

 

Could be worn out radiator support bushings

 

I took a look at those and they look pretty fresh. The radiator didn't have much play to it

 

If they original they’re worn out, it’s the inside part that wears. I chased a clunk for a bit. It was these. Easy to replace.

 

Do they have some sorta metal sleeve inside that?
A gen7 Corolla I tool around on has metal inside the rubber mount supports
I have never inspected these on the taco and it is 28 years old

 

Yes they do, when they’re worn out the radiator support can drop and bounce on the frame.

 

GLA!

 

I had loose sway bar end links and it sounded very similar.

 

Would the radiator have extra play if they were bad?

 

Just to add two more possibilities worth inspecting and ruling out:

1. Front Diff Mount Bushings - when these are worn (and anytime oil leaks or is spilled it finds its way down to these - and hot oil will accelerate the bushings wear), it can allow the diff to clunk against the skid plate. Easy way to rule this out is remove the skid plate and if symptoms go away, this is your cause.

2. Rear Wheel Bearings - mine clunked when turning into driveways that had incline or declines to them (basically when weight would shift off of one axle shaft/bearing). It eventually progressed to every small bump causing an audible clunk that I could feel through the seat and floor of the cab. I replaced the wheel bearings out of desperation (after nothing else fixed the clunk), and the issue was immediately resolved. Interestingly the typical jack up the rear and try to shake the tire at 12/6 or 3/9 didn't yield any play, but the bearings were obviously shot once I pressed them out (sounded like maracas when I shook them ).

 

I don’t think so because it’s attached to the radiator support. That’s what moves

 

What diagram might I find that part in
I tooled around the diagrams I have for my VIN and didn't readily see it
Are those supports only for the radiator for the automatic transmission?

 

I have a RWD do that rules out #1, #2 however seems possible. when i bought it in may I think the guy said he had all of the bearings replaced like a year before I bought it when he was doing the suspension. I do not remember though. since the clunk has started I've slid it around a little bit and done a donut or two, stuff that usually will shift the weight around rapidly, and it wont do it. I've also rocked the rear end side to side pretty hard and had no sound, i appreciate the response though, maybe it is that

 

Whoops how'd I forget you said you had a Prerunner.

Regarding the rear wheel bearings, just know it can be very hard to duplicate a clunk from them by rocking the truck

 

thanks, buddy

 

curious if you had to remove the whole radiator to replace these?
i will be looking into the FSM to find the relevant torque specs, etc.

 

no, but removing the grill and bumper makes it easier to access.
Basically do one side at a time, loosen bushing bolts, with a piece of wood and a jack, jack radiator support core and remove and replace bushing. Easy.