A lot depends on how much of it there is... if its just speckles of it, like small drops, any tar remover or solvent based product should be able to take it off easily. WD-40 will work in some cases like 99_Sierra mentioned above.
If you have large blobs of the stuff, or it completely covers the surface then you might need to get a bit more extreme to get it all off.
A forum community dedicated to GMC and Chevy full size owners and enthusiasts. Come join the discussion about Silverados, Sierras, and other full size trucks performance, modifications, suspension, lift kits, tires, maintenance, and more!