If you ever find yourself near a tour bus, it would behoove you not to stand behind the exhaust for this very reason.
Mechanic Trent Smith shared a cautionary tale of sorts showing just how hot a diesel bus’s exhaust going through a parked Diesel Particulate Filter regen cycle can get. With the filter temperature reaching over 1,500F, the exhaust temps got so hot, the asphalt underneath the tailpipe was literally boiling itself into a forbidden BBQ sauce.
Check out his Tik Tok below.
@smittsbits exhaust temps reach in excess of 1500 degrees Fahrenheit ##PSA ##diesel ##DPFregen ##bus ##cummins ##ism
♬ original sound – smittsbits
Back in 2007, diesel trucks, including big rigs, left the factory with diesel particulate filters already installed. Designed to filter out diesel particulate matter before it reaches the air, these devices significantly cleaned up tailpipe exhaust emissions.
And if you live in a state with California emissions standards, in 2014, older diesels needed these systems retrofitted on.
A routine maintenance task is regeneration or DPFRegen where the truck, either actively or passively, raises exhaust temps well above operating levels to burn accumulated soot and ash into Carbon dioxide.
While parked regen on grass and asphalt is not advised because it can literally set grass or asphalt on fire, sometimes there is no choice.
Here, this parked bus can’t drive around unless it goes through its parked regen cycle. While asphalt melts at around 200F, the temp where it’s hot enough to pour, the black stuff boils at over 570 F.
If we take this mechanic’s word, that exhaust tip and gas temps shooting out are extremely hot, hot enough to boil asphalt.
So, the next time you’re standing around, waiting for your diesel parked regen to complete, don’t stand behind the tailpipe.
And if you’ve got a fifth-wheel trailer, be aware of where your diesel exhaust is shooting its hot gases on. You don’t want that to melt!
