Black Exhaust Tips

They're all sooty. Some more than others.

I got a 10 spot says if you take the exhuast down on the 3406E, you'll find some.

You see it all the time, some trucks have it literally running down the sides of the stacks, while others just look kind of grey on the inside.

The more efficiently the engine burns the mixture, the cleaner the stack.

And you're correct in your assumption. It could be a sensor, or it could simply be the current ECM set-up.

 

OK but you said the inside of the pipe, I took it as down in, I'm guessing your talking about the side toward the cab as being the inside?

 

Yes.

 

Alot of the soot build up can also be depending on the style of tip on your stacks. A miter cut will have alot more soot further down then a stove top and a turn out will hardly have any soot build up.

 

some truck stacks need chimney sweeps

 

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