Undercoating

silvrmax04

IBEW local 24
Apr 18, 2007
96
2
8
md
I am looking into having the truck undercoated. A local shop does this that my sons freind works at. Has anyone had this done? How do they clean it before applying the coating. My wife has an excursion that needs it more than mine. Hers would be first on the list as mine is very minimal and thinking it will preserve the underneath for the long run. Especially in this rust belt I live in.
 

OregonDMAX

NOT IN OREGON, NO DURAMAX
Apr 28, 2013
3,964
8
38
36
Goodyear, AZ
I did it working at a Toyota dealer. I will never in my life ever do it to anything I own after see what I was getting paid alot of money to ruin other people's cars.
 

silvrmax04

IBEW local 24
Apr 18, 2007
96
2
8
md
That's what I am afraid of. Them spraying it all over everything and the rust just trapped in there to keep eating.
 

jliddle

New member
Jun 30, 2012
331
0
0
NC
Just hit any rusty spots with a wire wheel. Etch primer. Then acrylic enamel.

Pressure washer will do wonders to brown rubbery GM undercoating
 

PureHybrid

Isuzu Shakes IT
Feb 15, 2012
3,517
501
113
Central OH
Get all the loose scale off, paint it with Por15, then coat over it with Por15 topcoat or 3M undercoating. Spray inside of rockers and cab corners with Fluid Film.
 

N2BRK

Well-known member
Dec 31, 2009
2,060
392
83
how far away from Mechanicsburg PA are you? I go to Line-X of Cumberland County and get my truck done with Krown. It's awesome and cheap/easy.
 

bmc1025

Member
Jan 25, 2013
521
0
16
Big Bone, KY
Paint and some kind of oil or Fluid Film works much better in my experience with my plow trucks. Any sort of thick rubber undercoating seems to trap moisture and go unnoticed until a large area bubbles off.

I wire wheel the frame and paint with industrial rustoleum semi-flat paint out of spray cans just for ease of use. Chassis Saver is another good option. For the body seams I wire brush and phosphate treat the rust then use etching primer and finally enamel paint.

I have a fluid film gun with a straw that can be sent through holes in body panels. I spray bulk FF under the body, in the bottom of doors and in the engine bay every fall.
 

bmc1025

Member
Jan 25, 2013
521
0
16
Big Bone, KY
how far away from Mechanicsburg PA are you? I go to Line-X of Cumberland County and get my truck done with Krown. It's awesome and cheap/easy.

I'm not a fluid film fan boy by any means but have used Krown by the cases side by side with Fluid Film and for salt equipment the difference is night and day. On the salter chains Fluid Film lasts almost the entire season but it only took a few storms before the chains started rusting with the Krown. I still have a case of Krown left and use it occasionally during the summer.

The Krown is like a sticky kerosene/chainsaw bar oil mix and the Fluid Film is a lanolin based product that seems like more of a wax.
 

N2BRK

Well-known member
Dec 31, 2009
2,060
392
83
Either is better than nothing :) GM recommends against Fluid Film because it eats the factory waxy frame coating, which is partially why I did Krown, but if your coating is shot already then I suppose it doesn't matter. :thumb:
 

silvrmax04

IBEW local 24
Apr 18, 2007
96
2
8
md
So the Krown and FF are an oil based? Does it harden or eventually wear off? Is is greasy under neath when you have to work on something? I did a search and saw some utube videos. I was looking for something permanent. I guess nothing is permanent when it comes to salt. Maybe I just be better off scuffing,sanding, and painting with a rust preventative paint. I have used por 15 and love it on bare metal.
 

PureHybrid

Isuzu Shakes IT
Feb 15, 2012
3,517
501
113
Central OH
I'm not positive what the Fluid Film is made of, but no, it never dries (will stiffen up a little bit, kind of a waxy feel). That's why I only recommended it for the insides of rockers and cab corners. I would de-scale and paint everything else.
 

gassux

Member
Mar 14, 2010
363
19
18
Paint and some kind of oil or Fluid Film works much better in my experience with my plow trucks. Any sort of thick rubber undercoating seems to trap moisture and go unnoticed until a large area bubbles off.

I wire wheel the frame and paint with industrial rustoleum semi-flat paint out of spray cans just for ease of use. Chassis Saver is another good option. For the body seams I wire brush and phosphate treat the rust then use etching primer and finally enamel paint.

I have a fluid film gun with a straw that can be sent through holes in body panels. I spray bulk FF under the body, in the bottom of doors and in the engine bay every fall.

I do the same but I spray WD40 underneath periodically. I'm not a fan of FF, it was pushed so hard on plowsite and i wasnt impressed.
 

Dozerboy

Well-known member
Jun 23, 2009
4,918
497
83
TX of course
I had a 5 gallon bucket of hydraulic oil leak in the bed of my work truck while on a long trip I don't think it'll ever will rust. However I'm not sure I would trust the brakes or that anything rubber on the truck will last.


Sent from my iPhone using Tapatalk
 

WVRigrat05

Wound for sound
Jan 1, 2011
3,081
4
38
36
French Creek, West Virginia
Never undercoat anything you plan on keeping, it's a joke and hides dangerous rust holes. My ford ranger frame looked brand new till I hit a nice hump getting some air and the frame broke, after I peeled the shit off, the frame had huge spots all over it.

I kept my LLY frame painted, it was ok but you had to stay on it.

On my LMM, I have kept the factory coating either wd-40'd or some oil/diesel. It's held up like new for 3 winters, I use a thin layer of 3m under coat on any spots that pop up as it's matches the factory stuff well.