Black Soot all over on the roof of my truck

Discussion in 'Heavy Duty Diesel Truck Mechanics Forum' started by lonestar244, Oct 18, 2025.

  1. Goodysnap

    Goodysnap Road Train Member

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    DEF eliminates soot?

    It is truly scary how many have no clue how these systems operate.
     
    Arctic_fox, 201, Diesel Dave and 2 others Thank this.
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  3. Diesel Dave

    Diesel Dave Last Few of the OUTLAWS

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    I have “White”(ash) soot all over my tips.
     
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  4. Oxbow

    Oxbow Road Train Member

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    I have very rudimentary knowledge of emission systems, but I'm fairly certain DPF is for soot, DEF/SCR for nox, and EGR just to make shops money!
     
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  5. 201

    201 Road Train Member

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    high plains colorado
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    Hope this works, I remember entire sides of trailers black with soot, like the ICX truck or the orange R190 or the "Dual" truck, that I think is an Autocar. The Mack R model I drove was particularly smokey in between shifts. Blew a cloud, it did. I remember they had a device called the "puffilator", and was supposed to "eliminate the puff" of smoke. Old Detroits you could see them a coming a mile away. In fact, the reason for "up pipes" was to blow the soot over the cars. Check this out:
    Vintage Trucks: A Colorful Gallery Of Old Diesel Semi-Trucks And Their Exhaust Stacks - Starting With The Smallest Muffler Ever - Curbside Classic
     
    Last edited: Oct 19, 2025
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  6. lonestar244

    lonestar244 Bobtail Member

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    Thank you for your detailed response. I will monitor it and check the pipe off near turbo just to make sure. Thanks.
     
    Rideandrepair Thanks this.
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