TLDR at bottom lol

First off, I dont usually post much about issues I have with car parts and this thread is not to bash anyone or place any fault anywhere. I am truly hoping to find something Ive missed or get other ideas of something to look at to figure out where this noise is coming from. I really like the ride and how much better my truck handles with these shocks and would love to solve the issue.

I installed these (all 4) back in the summer and put about 4k miles on them before the noise in the rear started. It started off as a small, light clunk and it progressively got worse until the clunk was there all the time. It basically sounded like something hitting the floor or like a blown strut sounds in a car. I figured in was my old 300k mile control arms so bought all new OEM uppers and lowers, OEM track bar, OEM sway bar links and bushings and replaced all of it, nothing changed. I figured theres no way the new shocks are making noise so i didnt even look at them to start with.

I laid under the truck and had someone rock the truck up and down and i could feel the clunk in the shocks and axle housing so i took one at a time off. The noise lessened with one removed and completely went away with both removed. I put them back on and the noise returned. (I made sure all the bushings were in the correct order, and everything has been tightened with wheels on the ground under the full weight of the truck.) I contacted dobinsons and sent the rear shocks back to them to be looked at. They couldnt find anything wrong other than the lower bushing sleeves that I beat up removing the shocks 3 or 4 times through all the troubleshooting so I paid to have those replaced just in case.

For the few weeks while the shocks were shipped out, I picked up some old, used bilsteins locally (since i had trashed all my old stuff) so i could keep driving my truck to work. The rear suspension is completely noise free with the old shocks on it.

Got the shocks back a couple weeks ago, put them on and the noise was gone. Well, they made it about a week and the noise came back. Im basically out of ideas at this point and have been told that theres no way the shocks are making noise so i figured i would post here to see if anyone had any other ideas or something theyve come across with other suspensions.

TLDR;
new shock noise started after 4k mi, rebuilt shocks, noise came back a week later.
no noise with old shocks on the rear.
replaced....
All rear control arms, track bar, sway bar links and bushings with new OEM
Newer Dobinsons springs at all 4 corners
All bolts have been checked and rechecked on entire rear suspension
Nothing was tightened before truck was sitting on the ground and all bushings are in the correct order.
No rear noise with old shocks put on.

thanks in advance for any input or ideas

Someone mentioned their rear jack was loose and could possibly make the same noise. i got my muffler replaced, and i started hearing something similar over speed bumps and came across the thread that said it could be your jack moving around. i haven't bothered checking mine cause it only happens when i go fast over speed bumps. i'll check it soon. i have the whole suspension to replace on mine so haven't been to worried about the noise.

Its definitely not the jack. It is for sure from the suspension, I can feel the clunk in the shock and axle when laying my hand on either. It does it when on jackstands or sitting on the wheels, its easy to recreate by bouncing on the rear bumper or pulling down on the roof rack and making the suspension bounce. It seems to make the noise right when the suspension is changing from going up to starting back down. And it completely disappears with the old bilsteins that are on it currently.

Definitely weird. did you check the rear control arms??? maybe the ims are pushing on something or putting strain on something that the bilsteins aren't. are they the same measurements, length wise, etc???

i've heard nothing but good things about the IMS on reading all these suspension articles. i myself went with the bilstein/ome combo but haven't installed yet.

Same measurements as far as i know, and it only takes a very small movement in the suspension to make the noise. The noise didnt change at all when i replaced all the control arms with new ones so i dont think theres anything going on there. I went back through all the bolts when the noise came back the second time so i know everything is tight.

I thought about the different shocks putting a different load on the suspension but i cant find anything moving and there was no change in the sound when i replaced the whole rear suspension.

Have you talked to the shock people about what's going on?

I'm running their IMS shocks on the rear of my setup. I definitely have (what at least appears to be) suspension noise that has been driving me absolutely nuts. I can't confirm whether it's the shocks or not (I haven't gone through the process of removing them as of yet) but my initial suspicion was shock noise.

It doesn't happen ALL the time, but is most prevalent at lower speeds (when there isn't a tone of other noise happening) going over uneven road surfaces, like manholes and neighborhood street imperfections. I don't know how to best describe it.. but kind of sounds like a dull thud.. it doesn't help that all of my suspension is all aftermarket, but I have gone through every nut and bolts, even welded my adjustable control arms to make sure they weren't loosening up, and replaced the rear arms heim joints to a bushing style setup with 0 luck. Noise is still there.

Again, haven't confirmed 100% but this thread definitely sparked my interest. Mine could be as silly as my heavy RTT moving around on the rails of the roof rack (maybe) or maybe it's the same thing you're experiencing.. I guess the best way to tell would be replace them with a cheap throw-away shock and see if the noise is still there or not..

Yes, a lot. Even spent $150 shipping them to and from and having new bushings pressed in. Basically was told it cant be the shocks, has to be on my end.

On mine, i can feel the clunk while holding the shock or placing my hand on the axle or tire. Nothing that i replaced has changed the noise, the only time it went away was when the shocks got rebuilt (lasted a week) or when those shocks arent on it. Mine also does it over rough road or small, rapid bumps up and down.

heres a couple videos of the noise. The sound is more amplified with the phone laying directly on the frame, its not this loud in person.

passenger side - YouTube

hopefully the sound on this video works better than the other driver side video. stupid youtube making videos into shorts automatically.

https://www.youtube.com/watch?v=9yBkmd_hQuM

well, i can confidently say the noise im hearing is internal to the shocks. finally got a chance to completely swap shocks with my brother on his gx (also has the dobinson ims shocks). i put my shocks on his truck with his upper bushings and put his shocks on my truck with my bushings. the noise stays with the shocks on his truck so i know im not going crazy and theres nothing wrong with my truck.

I am considering the IMS set up myself, and will be watching this thread closely to see what Dobinson's does to rectify the situation. Thank you for posting

update....just got an email from dobinsons and they are going to replace the shocks for me. they have been responsive/helpful so far and ill be sure to update this thread after i get them put on.

Got the new shocks put on yesterday and all the noise is gone now. Like driving a brand new truck again lol. sending the old ones back so hopefully they can find out whats wrong with them.