Mach2

You have a very good point, the OP should give Dawn a try.

Nuke

If there's any grit mixed in the oil like you implied, I'd be sure to NOT wipe it. A pressure wash or a kerosene bath (the latter of which Goldenpony mentioned) would be recommended.

Synar

Castrol super clean ...................... spray on , rinse with press wash or hose down. That's it ! For future care, just put a good wax ( Auto glym ) is very good, if you got future problem like paint, tar, bugs, oil ect ................ just wipe it out with wax on a towel. It will come off very easy.

07 Stang

I was thinking the same thing. I would try Dawn Dish Detergent first. It will strip the wax, but that's no big deal to re-apply. You could put some in a spray bottle mixed with a little water, let it soak for a couple of minutes then spray off with a hose.

BAB GT

+1 on no rubbing, brushing, wiping, etc., until you use some type of degreaser and high pressure wash. Then a good coat of wax and you should be good.