Noticed dark patches of... crap on driveway as of late. Just realized today, it's in fact coming out of the exhaust at start-up. Dark matter of something, it's not oily or wet, it's just kind of powdery from what I can tell.
Bad photos, but you get the idea of what I mean. Why is this?
Edit: My mate reckons it's normal, and it's the very reason some shops do not allow reverse-parking close to the shop due to diesels spraying crap like this everywhere. I've personally never seen it before, or knew about it.
http://www.nissanpatrol.com.au/forums/
http://www.nissanpatrol.com.au/forums/