grease removal

[camino70]

I had a white `08 Silverado that slung grease all the time. Normal wash with extra pressure would normally do the trick. Now i have a black 2011 sierra that i can`t seem to not swirl for my life. It slung grease every where the other night in terrential down pour and it won`t budge with minimal pressure. What is it and how can I remove it?

The truck is opticoated, I tried pressure washer, onr as detail spray, one and griots shampoo.

Tia

Ron

[Richard Grasa]

Could be oil from the road. I`d spray it down with APC and let it dwell for a while, keep it wet with the APC and then a good rinse. Or if you have access to a foam cannon, give it a good foaming with APC or citrus degreaser mixed in and let it dwell then rinse. Or a strong Dawn solution may work. If none of those work, I`d then try IPA or mineral spirits. I`m surprised it`s sticking that much to the Opti-Coat.

[David Fermani]

Where is this grease coming from??

[camino70]

The more I`ve searched the more I believe it`s tar from the road. I hit it with apc and let it dwell a few times, I think it`s all gone now.