Opinions on Rubberized Undercoating

[97' 4 Popper]

I know rubberized undercoating is a pita to remove and if the surface isn't completely clean it can trap moisture causing problems. It usually gets a bad rep compared to fluid film. However I just got done working with a frame and rear floorboards that were coated in layers of rubberized undercoating. I was worried it was hiding rust, but the only rust I found was already visible. Underneath the coating it was in mint condition. Very small areas around the opening and holes where the coating stopped rust had just started. It makes a person wonder. If the surface you are working with is clean enough and you spray a good layer of rubberized undercoating it will seal up perhaps better? It should definitely last longer than a year versus reapplying fluid film annually.

 

[JEEPCJTJ]

I Fluid Filmed everything I could see and more. My Jeep was pretty rust free when I did that and I thought that the rubberized undercoat would probably help keep stones from making noise and chipping the paint in the front fenders so I sprayed some there about a week before the F-F. Well the F-F must have felt that the rubberized undercoating wasn't a great idea so it melted the undercoating and blended in with it. They both slowly wore away while driving in crap and now I just do the F-F every year.

 

[Rubicon88]

OTHER....
Berkebile PFC is the best stuff we use.
We undercoat service a bunch of vehicles here in the rust belt.
It's thick stuff...spray it on with a bedliner gun.
Works really well fighting/prevention of rust

 

[MichaelGH]

As with anything you use prep is key to long term success. I had the luxury of starting with a completely bare frame. I used Eastwood black Rust Encapsulator on the outside and then their internal frame coating on the inside. Prep prep prep cannot be stressed enough. Where you and I live are both brutal in Winter. Parking your Jeep in the Winter goes along way as well, if it’s not a dailey driver...

 

[TheBoogieman]

Eastwood for me.

 

[97' 4 Popper]

As with anything you use prep is key to long term success. I had the luxury of starting with a completely bare frame. I used Eastwood black Rust Encapsulator on the outside and then their internal frame coating on the inside. Prep prep prep cannot be stressed enough. Where you and I live are both brutal in Winter. Parking your Jeep in the Winter goes along way as well, if it’s not a dailey driver...

I agree with what you're saying about prep, nothing else matters. Most of the floorboards had rubberized undercoating with impact orange topcoat underneath and a grey color base paint underneath the topcoat, other areas just had the base paint from the factory. I removed all of that and got to bare metal by needle scaling and wire brushing the rust areas then back to wire brushing everything for final finish. Now I'm gonna use acetone, clean up the acetone. Then start at a lower grit like 200 and go up to probably 800 grit sandpaper on everything. Then Eastwood rust converter then encapsulator on areas that had rust. Then rustoleum rusty metal primer 2 coats, rustoleum topcoat 2 coats. Then some type of fluid film for areas that are rust prone. I will be using rubberized undercoating only on the wheel wells for now because it's fairly sterile surface and easy to remove in that area.

Eastwood for me.

What eastwood product are you referring to exactly? I have eastwood internal frame coating, but nothing for the outside. I also have the converter, encapsulator, and high temp paint.

 

[TWiG01]

Another vote for Fluid Film. It’s cheap, easy to apply and works great. Also, there is very little prep involved (just make sure undercarriage is clean).