Undercoating

[Motor City GMC]

I just bought my new project, a 79 k30 from California, im in Michigan so i want to have the entire underbody undercoated before it sees any snow, salt or really anything, but i really dont know what to use of have done.
I want it to look nice and clean, i dont want any of that nasty crap thats just slopped everywhere and then if/when work has to be done its #1 a mess and #2 twice the amount of work because that stuff is slopped everywhere.
So what have you used?
Did you do it yourself or where did you have do it?
What do you suggest?

[324matt]

I used the rustoleum PROFESSIONAL grade in a can. Its great. I used 20 cans on my underside. I coated the entire frame, gas tanks, axles, everything. I like it.

[Motor City GMC]

Has it held up pretty good?

[tylerg85]

That's what I used on my frame last weekend on my duramax. Curious to see how it holds up

[324matt]

So far so good. Dont get the regular stuff. Make sure to get professional grade. Its like $8 a can.

[Motor City GMC]

I might have to try that. Im just worried about salt, and getting the most protection possible. I honestly never thought of that stuff, my mind went straight to the bedliner type of stuff.

[greg64]

I like por-15. It works, but requires a lot of prep work. Not ideal if you're not going to take everything apart.

[Motor City GMC]

I was told that por 15 will only work on rust though....i was told at a local paint shop to use it on the roof of my cab where the california sun had baked the paint off and left bare metal that turned to surface rust, and then to just prime it to get me by jntil i was ready for paint

[andrewmp6]

A guy on youtube used a non stick coating on his frame and suspension.If you want to see what he used https://www.youtube.com/watch?v=YxlVY2Kpt4g

[bigguy]

I've always used 3M undercoating when I worked in body shops. I'm getting ready to spray the underside of my truck using raptor liner. I had some left over and I really like the texture when sprayed through a paint gun with a 2.0 tip.

[Keith Seymore]

I was going to try some of this stuff (in the doors, rockers, fender inners, ect):

Originally Posted by rich weyand

Here's another product you may want to know about. The aviation boys use this to keep oxidation from occurring in airframes. You spray it into voids, and it creeps into everything and keeps it from rusting. This stuff will walk 12" up a vertical surface. I spray it into the doors, the rocker panels and the tailgate very liberally -- enough to have it pool in there, and some will run out on the floor. It will coat the inside and keep it from rusting. The aviation boys re-apply it annually during annual inspections.

http://www.skygeek.com/10013.html

[Motor City GMC]

Bigguy is this the stuff like your talking about?
Anyone ever used this???
Amazon.com: 3M 03584 Professional Grade...

[Motor City GMC]

And would you guys just spray it on everything or would you try to avoid things like brake lines etc... in case of future repair?
Any need to degrease before i spray this stuff?

[cadillac_al]

I prefer high quality paint to undercoating. If you get a scrape or scratch in the undercoating, the undercoating will hide some developing rust until a big chunk of undercoating falls off. I never had any spectacular results with undercoating but I did use a lot of 3M. I did the underside of my truck in moisture cured urethane 2 years ago. It's still too soon to tell how good it is but it is definitely holding up better than the epoxy primer and polyurethane paint on the body. I am going to do the body over again in MCU this year. This is the stuff if you're interested.

http://www.masterseriescoatings.com/index/