Rear suspension noise after fluid film application

[Chepachetchevyguy]

Hey everyone, So I got my new truck in February. A 2020 Chevy 2500 cc lt trim. Gas engine. So living here in the rust belt of the northeast the best thing I have found so far for rust prevention is fluid film, so I sprayed the entire chassis and underbody of my truck about a week after I bought it. Few weeks go by and the rear suspension starts to squeak and clunk. It has gotten a little worse as the weather has warmed up, now I can tell the squeak is clearly the shackle bushings, and they even squeak just by stepping on the running boards or back bumper now. The clunk I haven’t figured out yet but it seems to only be at low speeds on unlevel ground. It can be noticed by shaking the truck side to side by the hitch when parked. I have fluid filmed a few other of my own vehicles and a few for friends, no complaints from any others but none of them were brand new either. Fluid film does state that it can cause certain types of rubber to swell, and I assume this is the shackle bushing squeak. So my question to everyone, is anyone else having any rear suspension clunks? Low speed particularly? Anyone else have experience fluid filming a brand new truck?

[samuse]

I would switch to LPS 3.   

 

Fluid Film is hard on rubber in my experience too.  

[unit]

I have not experienced any squeaks or clunks in my 2500HD nor have I used Fluid Film on the truck.  If you think the Fluid Film is the cause of the squeaks, take the truck to a magic wand type car wash and clean the springs and bushings using soap with high pressure spray.  Dirt and Fluid Film residue should wash off.  Oily substances like Fluid Film are dirt magnets.  You may have salt and road grit build-up where it's not intended and it could be creating your problem.

Edited May 30, 2020 by unit

[Jrscrib]

Fluid film is a bad joke. I cause the plastic that is in the springs to stick causing the noise. It also as it states cause rubber to swell destroying wires and seals in the connectors. I have personally replaced two chassis wire harnesses because of fluid film. Not to mention it wipes off the factory undercoat.

[GTBensley]

I fluid film my truck (2016 2500hd) and also have noise from the rear end after application. I believe its the rear spring shackles or bushing as well but can not understand why. Worse in warmer weather and basically gone in the winter. 

 

I would hardly say FF is hard on rubber and wiring harnesses. Been using it for years on many vehicles and it doesnt seem to cause much issues besides this clunk.

 

Oil on the other hand....that ruins rubber very quickly. 

[Rmcameron89]

I have the same exact issue with my 2020 Chevrolet Silverado LT diesel. got my truck fluid filmed and having the same noise!!! How do we fix this. Obviously can’t undo the fluid film 

[Jesse R]

I came across this post and had the same issue with my 2022 Chevy 2500 custom. I’ve always used fluid film and it’s saved/preserved my trucks in the past. Figured I’d share my experience with the new one.  A few days after the application I started noticing the “clunk” at low speeds around corners and unlevel ground.  The leaf spring bushings also creeked when you jumped on the rear bumper. Here’s what I did to fix. I jacked the truck up by the trailer hitch until the rear wheels came off the ground. I simple greened the crap out of the leaf spring bushings and the leaf ends where the plastic pieces are present in between the leafs. I then power washed these areas. Be careful. Don’t get too close or you’ll blow the undercoat off!  Test drove it after. Didn’t seem to help. I then jacked it back up again and sprayed silicone lubricant on these areas, and what do you know?  Back to being quiet again!  It’s been about 2 weeks and still quiet!  Hope this helps!  I was nervous for a while that my brand new truck had permanent damage. Going forward I’m just going to avoid these areas with FF on next years application. 

[JustinB60]

On 12/16/2021 at 5:09 PM, Jesse R said:

I came across this post and had the same issue with my 2022 Chevy 2500 custom. I’ve always used fluid film and it’s saved/preserved my trucks in the past. Figured I’d share my experience with the new one.  A few days after the application I started noticing the “clunk” at low speeds around corners and unlevel ground.  The leaf spring bushings also creeked when you jumped on the rear bumper. Here’s what I did to fix. I jacked the truck up by the trailer hitch until the rear wheels came off the ground. I simple greened the crap out of the leaf spring bushings and the leaf ends where the plastic pieces are present in between the leafs. I then power washed these areas. Be careful. Don’t get too close or you’ll blow the undercoat off!  Test drove it after. Didn’t seem to help. I then jacked it back up again and sprayed silicone lubricant on these areas, and what do you know?  Back to being quiet again!  It’s been about 2 weeks and still quiet!  Hope this helps!  I was nervous for a while that my brand new truck had permanent damage. Going forward I’m just going to avoid these areas with FF on next years application. 

 

 

For those of us who are not very knowledgable about suspension part names can you include a photo of the area you did this work to?  I am about to spray a product similiar to Fluid Film under my truck and want to avoid this area too...