I stripped down a 1982 Grand Prix last year and the frame was not painted at all. Instead, it was coated with a waxy black substance that looked like flat black paint at first glance but scraped off really easy and cleaned up with lacquer thinner. The bare metal frame was still shiny like new underneath. It held up better for 30 years and 150,000 miles than any of the painted components under the car, most of which had surface rust all over them. What is that stuff? Where can I get some?? I read the description of Eastwood's "Heavy Duty Anti-Rust" and thought it would be the same (http://www.eastwood.com/ew-heavy-duty-anti-rust-aerosol-black-13-5-oz.html) but I ordered some and seems to be the same rubberized undercoating that I can get at any store. This stuff was thicker and felt more like wax than tar or paint. This is not off-topic: I'm not asking what to use on a 1982 frame, I am asking what GM used on that frame so I can use it on my '51 Chevy! I drive my cars in call kinds of weather and I do not like rust.
Honestly if you hate rust and want to avoid it then you need to forget about that GM stuff and get some of this paint. It's about the toughest best rust paint you will find. It does a nice job. http://www.kbs-coatings.com/rustseal.html
A friend of mine worked for Dana Parish and said they dipped their truck frames for GM in paraffin wax. Maybe that's what you are describing?
i believe the waxy substance is just that....wax... i bought a 2008 chevy siverado , had same coating on it .in voice said wax coating for frame.... suprising how detailed the invoice was for my new truck....... 1/4" frame metal thickness///should last for a while....just pulled it through the mud in pennsylvania-job related........$$$$ worth it though.....kev
I worked at GM on the frame line , I hated that mess on the frame , was black as the frame every night when I went home ... Dont know what it was mixed with but it was black tar like roofing tar mixed with some kind of thinner ... I would paint it ... Just my 2 cents ....
Well it wasn't tar because it was still soft and flexible after 30 years and 150,000 miles. No drying, no shrinking, no cracking, and we scraped it right off with a scraper and then wiped the remnants right off with some lacquer thinner. I'm thinking it really must be some sort of wax like someone else said. My plan is to use it OVER the paint I already put on my frame, although if I'd had it before I painted I'd have used it on the bare metal since that obviously worked so well.
Why not go to the local GM dealereship and ask them. I'll bet they can get the stuff for you. It may have even been a dealer option.
I seem to recall that in the late 70's or early 80's one of the aftermarket rustproofers that were applied to new vehicles had wax in it. My uncle bought a new truck and paid for it to be applied. He claimed that the stuff wouldn't completely harden, and if scratched, it would flow enough to repair itself. Although I cannot say if it actually worked. He died and the truck was sold, so I wasnt' able to follow it over time.
This is what was very common, but the first part of the corrosion protection process on OEM frames and sheet metal is a "phosphate" coating. The "waxy" undercoat protected the original phosphate coating on the frame. Read this: http://en.wikipedia.org/wiki/Phosphate_conversion_coating
A few years ago I drove past a wreck where someone had rolled about that same year Gran Prix, a typical old beater from the looks of it. The rear tire hung up on the culvert where someone's driveway crossed a dtich and it had torn the entire rear 2/3 of the frame off the back of the car, with the rest of it on it's side and the frame bent like a pretzel with the tire in the ditch holding the car up. It's damn near impossible to find one of those G-bodies that hasn't at the least rotted the frame out behind the rear axle. I don't know where your car came from, but it must have never sat anyplace damp nor been driven in the snow. The stuff is junk as far as I'm concerned, any real test of weather and it comes right off. Then they rot. Even my own '87 Pontiac wagon, which was not in that bad of shape, died of frame rot and when we did scrap it, it had rotted out around most of the body mounts in the same way - as long as the car stayed on it's wheels it was fine, but if you lifted on just the body, the frame would have come off.
I had forgotten all about the frame rot problem! I grew up in northeast Ohio and they were all rotting out when they were less than 10 years old. Around here (Joplin, Missouri) things just don't rust that fast. However, if I remember right the frames all rotted from the inside out, right? But your point is well taken: it might work better than a thin coat of paint but it certainly isn't some miracle product. Incidentally, if you ever want a rust-free G-body I recommend getting one from Oklahoma or this region of Missouri. There are still dozens of them running around with not even a rust spot. The frame on the car I'm talking about was absolutely rust free and the floor pan only had light surface rust. (And it sat outside in the grass for at least three years before I bought it!) Either that or move down here - it sure makes it easy to attend the HAMB drags.
Just called my local GM dealer. The guy knew exactly what I was talking about and says they don't carry it and haven't for years and he has no idea where to get it. His guess is that it was hazardous (either health or enviro) and isn't sold anymore. I guess I'll stick with traditional undercoating. Thanks for all the replies, guys.
I have a 92 Toyota truck that has a similar coating. It's like wax or cosmolene. When they applied it they specifically cleaned it away from the VIN stamping area. Despite all kinds of body rust my frame is rust free!
Actually, I think it's the Daubert Nox Rust X-121B. http://www.daubertchemical.com/res/pdfs/pi_2011/121_X_BLACK_NOX_RUST_PI_Sheet.pdf Supposedly available from ECP Inc. www.ecpinc.net
The paint we used at the local factory was very much like what was on the frames. We called it prime dip. That stuff was some kinda dangerous. You could not hardly breath when you were in the booth with it. Our explosameter (sp) would peg to the red side when you held it a foot in to the tank. We dipped wheels, core supports some brackets and assorted other black parts in it. You know hard it is to get the black primer off some GM wheels. We had to dump that stuff ever so often to get lost parts out of it. The engine crank pulleys are still black. Wonder if they still use that somewhere.
I have found it at a couple of distributors...smallest quantity is 5 drums, 54 gals each! It runs $6,500 - $7,500 and has a shelf life of 1 year. I'd be looking at some Chassis Saver or POR-15.
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