Seeing some DPM on the back of my car - UPDATE to the UPDATE

Originally Posted by BMWTurboDzl

You live in Houston. The VOC's and burn off (flare) blowing in from Deer Park and Pasadena could easily cause that IMO.

Hah, if that were true then my white truck would show it well

Looks like a common concern on many different makes and models, in other forums.

Are you really concerned about it?

The rear of the car is the low pressure zone so any road dirt, dust, soot from brakes and exhaust will settle back there, especially if it is wet or moist.

I've got a black car anyway, who cares?

I'm pretty sure just about any car will have some amount of build up back there. Do a wipe test!

Well I had to pick between be concerned about this or about doing oil changes early ....

Originally Posted by János

I get a very fine layer of grime around the back of the car. Unfortunately I don't wash the car very often (it is parked outside and gets coated with city dust within a few hours). I think the stuff at the rear is probably road dust, pollen, and a little bit of soot. Thank goodness for Tasman Green.

My tailpipes have a dirty spot at the bottom, very similar to the pic posted by grapes87. It was quite a bit less noticeable several months ago so I think I'd better see about polishing them. Would Brasso or toothpaste work?

My pipes looked similar to the pictures that were posted. I'm not crazy about keeping my car clean since I park it outside, but I thought the pipes could use a little attention. I had some Meguiar's Mag Wheel and Aluminum polish that I use for another car. Five minutes and they cleaned up like new.