Ok I noticed something odd the other day, my entire rear quarter panel had a light coating of what looked for all the world like the type of black soot you get out od a diesel. As cool as it would be to have a diesel Dak, mine isn't. So, what gives? Is this common & normal or should I panic?

 

I've always gotten a little on mine, just above the exhaust pipe where the bedside curves under. It's not an issue as far as I'm concerned if it's not excessive. When you say "entire rear quarter panel" exactly how big of an area are you talking?

 

Most everything aft of the axle, about 2/3 of the way up the side [allowing for the curvature of the fender]. I would take a picture, but this isn't the clean season...

I just never got this on my '99, but it's a 5.2. My 2000 Durango doesen't do this either, but the pipe goes out the back, so maybe it does, just on the hood of the car behind me. ;-)

 

Do you start the truck and let it warm up often?

 

Any check engine lights?

 

No I don't warm it up, and no Check Engine or other lights.

 

How long is your daily commute and what state do you live in?

 

Commute, 5 miles, but I also drive during the day, sometimes 4-500 miles. I live in IL.

 

Black deposits usually indicate a rich condition. One thing to do is verify your short and long term fuel trims. You can do this by using a "good" OBDII code reader that shows data in live timing. Advance Auto Parts carries one that is pretty decent. $249.

 

Your exhaust contains water vapor that normally goes unnoticed when your engine is thoroughly warmed up. In really cold weather, or on short trips, it can condense out and "wash" the crap out of your exhaust system, which it then sprays out the tailpipe. That might be what you're seeing on your quarter panel.

That said, it shouldn't really be dark black unless you're running rich (like was posted above), but I would think you would be seeing other problems if it were that rich, like a check engine light or stinky cat.