Good ol' claybar. Another product you guys might be interested in:

http://www.eshine.ca/aquartz_iron_cu...502.php?cat=10

It smells absolutely rancid, but it works very well. Spray on, let dwell, it dissolves ferrous metals, so it's essentially like liquid claybar. I use it before I clay particularly contaminated paint.

 

pic. of impala i was speaking of, what do you guy's think? clay has little to no effect on it.

 

Well, there's your problem. It's the stink leaking off that GM badge.

On the side I was thinking maybe tire shine sling but that shouldn't be on the front bumper.
Have you tried a small spot with some type of petroleum solvent like goo gone to see if it might be some kind of petroleum product?
This sounds gross but with all the cattle trucks here in the TX panhandle you get stuff on your vehicle regularly that looks like that. Mixture of manure and urine that flies out the back of those stink waggons. But a good wash and/or clay have always gotten that stuff clean.
g'luck

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we bought it from the in-law's this spring and i can tell you it has never had a wax job. when i washed it before trying the clay my drying towel stuck like i was trying to dry sandpaper. i can almost guarantee it has never had any tire dressing on it. would a more aggressive clay work? i used the mequiars smooth clay. worked great on my truck.

 

Based on those pictures, I'm now leaning towards some kind of stain. (JGG might be talking about the same thing.) Have you tried a cleaner wax or even a very mild polish? Most off the shelf "waxes" such as Meguiar's NXT 2.0 (which is actually a synthetic sealant) have a cleaner component to them. Have you tried that?

 

i have both mequiars nxt 2.0 and mequiars cleaner wax. i'll give those a try.

 

That still looks like contamination to me; just deeply embedded and long neglected. I'd try a slightly more aggressive claybar (there are different grades available, the ones at auto parts stores are generally "mild").

Alternatively you could use a decon kit (http://www.autogeek.net/finish-kare-...ng-system.html); but that's a little more involved.

I'd probably approach it with an APC + medium grade clay, and if that wasn't making enough leeway use a decon kit or AQ iron cut.

 

Avoid claybar like the black plague for this...it is long term iron oxide staining from environmental exposure. Go to your nearest auto paint supplier, they will have iron oxide remover/neutralizer, then apply denatured alcohol to the paint- wipe down, this should remove most if not all of the residual contamination, apply hand glaze, then polish (no cleaner wax stuff), then wax or paint sealer. Only use claybar if wet sanding is required.

 

You never learn do you. Must be nice to still be living in the 1970's.