Do you know about DPFs?

Got enough brain space to accommodate another acronym? DPF. It stands for diesel particulate filter, and it's a hard-workin' guy you'll find on '07 and newer diesels. A DPF works in conjunction with the oxidation catalyst to remove a majority of the NOx and particulate matter (think black, cough-inducing soot) from burned diesel fuel. Soot is a natural byproduct from the combustion of diesel fuel. While you can't see what's happening inside, it goes like this: Inside the DPF is a porous honeycomb structure that catches the soot as it passes through. And after the soot builds up over time, an on-board computer controls fuel injection to allow unburned fuel to enter the filter at measured intervals where it flares off and generates increased temperatures that incinerate the accumulated soot. The result: soot is chopped by over 90-percent and NOx emissions are slashed in half.

Check out these up-close and personal shots: DPF on the 2007 Chevy Silverado 2500HD Duramax Diesel and the 2008 F-250 Super Duty Diesel's DPF. Yep, we crawl right under these trucks to grab shots of the stuff you won't find anywhere else.

part of the 2008 F-250 Super Duty's clean diesel tech - photo © Adrian Gable