I went hunting today and had a regen while in some tall grass. While it smelled a bit funky there were no fires. And the tall dry grass was pushed up against the DPF filter and tailpipe.
I always wondered about this and now that I have done it I guess that fear is now put to rest.

 

For clarification, what's the outside temps? Grass dead or still alive?

Grass is still green here, so that's one reason I'm asking. I'll agree it doesn't seem to get super hot though. They've been out way too long without all the horror stories we heard from catalytic converters back when those first came about.

 

Grass is all dead here. It will be -25 next week.
It was +15 today. A heat wave!

 

likely too cold under the truck, even with the regen.

 

It's 59 here overnight and I'm freezing. I can't wrap my mind around those temperatures.

 

In the West we are very careful about wildfires. One took 300 homes in my town, including mine. A different wildfire in its early stages burnt 4.5 acres per second ... very dangerous. As kind of a premonition before that, I was on a hike stopped for lunch and smelled smoke. I looked over my shoulder and about 6 feet away were smouldering pine needles at the sun's focal point of a broken Corona beer bottle bottom. Spooky. Please don't press your luck.

 

I'm pretty sure Richoman lives north of the border, and was talking about temps in Celcius, not Fahrenheit. However, -25C is still below zero (-13F) and is COLD!

 

If you hit -25, it doesn't matter much which reading you're using. Way too cold for me either way.

 

So very true. We had a wild fire here in western SD the middle of Oct that consumed approx. 65 square miles. At one point it was burning one square mile every 4-5 minutes. Amazingly no homes were lost, or was anyone hurt, just some out buildings, many miles of fencing, and winter hay for the cattle was lost. Along with somewhere around 300 cattle. A very brutal fire for those in its path.