Under body/Chasis Oil treatment

Dirty5P · August 16, 2019

All,

Im new to the forum, been reading a TON, and will be doing some work soon with pgamboa.

I picked up a new 2019 2500 duramax at the beginning of spring this year. Im in the northeast, and with all the liquid de-icer they lay down here im looking into additional ways to protect the underbody of my truck. So, my question is, do any of you have any experience with such products as filmco??? (not sure if i can post a link, so i didnt). I heard from one person locally that these sorts of products degrade the factory applied underbody coating and can create a big problem - id imagine if this was happening that they wouldnt be in business very long so id figure id ask all of you what your thoughts, opinions and experiences are with these sorts of products.

Thanks!

Icutmetl · August 16, 2019

I’ve never heard of Filmco. I’ve treated mine twice with Fluid Film since purchasing it new last November. It’s true that some products can soften the waxy coating that GM applies....oh well. I did enough digging about a year ago and found the manufacturer of the coating that GM uses and where you could purchase it. I’ve read where guys have used heated crapper wax, old oil, all sorts of stuff. I chose Fluid Film because it’s readily available and somewhat reasonably priced; I bought a cheap undercoating sprayer off Amazon to spray it, and it works great.

Dirty5P · August 16, 2019

2 hours ago, Icutmetl said:

I’ve never heard of Filmco. I’ve treated mine twice with Fluid Film since purchasing it new last November. It’s true that some products can soften the waxy coating that GM applies....oh well. I did enough digging about a year ago and found the manufacturer of the coating that GM uses and where you could purchase it. I’ve read where guys have used heated crapper wax, old oil, all sorts of stuff. I chose Fluid Film because it’s readily available and somewhat reasonably priced; I bought a cheap undercoating sprayer off Amazon to spray it, and it works great.

Awesome. Thanks for the info, Icutmetl!

stevejones · August 16, 2019

I've had good luck with Cortec VpCI-368D on my -98 K1500

Cowpie · August 18, 2019

I don't apply anything, that is primarily because I live on gravel roads and I don't need all that dust and dirt sticking to whatever I spray on the underside. If I lived in town, I might try one of the protections products.

Actually, I take a small stationary watering attachment on the end of a garden hose and spend a couple of hours spraying down the underside a few times a year to clean things out. I don't really have any appreciable rust on the underside. And yes, I live in the snow belt and they lay down the liquid deicer rather heavy at times.

For any rust that does develop, I am fond of a rust converter I get for my commercial trucks.

https://www.theruststore.com/Rust-Converter-Aerosol-P292C10.aspx

newdude · August 20, 2019

On ‎8‎/‎16‎/‎2019 at 10:34 AM, Dirty5P said:

All,

Im new to the forum, been reading a TON, and will be doing some work soon with pgamboa.

I picked up a new 2019 2500 duramax at the beginning of spring this year. Im in the northeast, and with all the liquid de-icer they lay down here im looking into additional ways to protect the underbody of my truck. So, my question is, do any of you have any experience with such products as filmco??? (not sure if i can post a link, so i didnt). I heard from one person locally that these sorts of products degrade the factory applied underbody coating and can create a big problem - id imagine if this was happening that they wouldnt be in business very long so id figure id ask all of you what your thoughts, opinions and experiences are with these sorts of products.

Thanks!

Daubert Nox Rust 121-B is the factory wax but sprayable. I'd get a couple cans of that and touch up any spots you see before winter. Fluid Film will take the wax on the frame off. Ziebart will interfere with the wax as well, and Ziebart will do nothing but trap moisture under it and rot the truck that way.

For the rest of the underside minus the frame, I'd go with Boeshield, Fluid Film or Krown. Boeshield would be my first pick as that stuff sprays on and sticks. You have to scrub it off the underside to remove it. Just a hose won't touch it, a pressure washer might, but regular hose won't.

Dirty5P · August 21, 2019

Wow! Thanks for the info everyone! Clearly i have some research to do, but sounds like fluid film is out of the running, not interested in a product that will dissolve the factory coating. Thanks for all your help!

carkhz316 · August 21, 2019

Fluid Film *CAN* loosen the wax coating, but it's not guaranteed. The remaining portion of mine is holding on just fine. My opinion on it is this: The wax coating will slowly flake and peel off by itself, leaving the frame to rust out. So do nothing to stop that, or spray FF (or equivalent) and it may knock the factory wax coating off, but it will flow and cover up where it was and continue to protect against rust. What's the lesser evil here.

Icutmetl · August 25, 2019

On 8/21/2019 at 9:27 AM, carkhz316 said:

Fluid Film *CAN* loosen the wax coating, but it's not guaranteed. The remaining portion of mine is holding on just fine. My opinion on it is this: The wax coating will slowly flake and peel off by itself, leaving the frame to rust out. So do nothing to stop that, or spray FF (or equivalent) and it may knock the factory wax coating off, but it will flow and cover up where it was and continue to protect against rust. What's the lesser evil here.

This guy gets it!

GTBensley · August 26, 2019

I use Fluid Film on mine and it does soften the wax....but I look at that as a good thing. Think of it like spreading peanut butter on bread-its soft and adheres well and is pliable....the jelly doesnt soak through the peanut butter and get the bread on the other side wet.

FF is doing the same thing making the wax soft. Before, it could peal off in large chunks and let rust between the wax and the frame but by keeping it soft with the fluid film it remains pliable and wont separate off the frame. Plus, the FF acts as a protectant as well. I know thats a weird description but best I could think of.

You do need to make sure to cover spots that get scratched (if you bottom out or such) but to me thats a small price to pay for keeping it clean.