What is the average cost of adding a lift axle?

Discussion in 'Heavy Haul Trucking Forum' started by AFC, Sep 18, 2025.

  1. MACK E-6

    MACK E-6 Moderator Staff Member

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    Sounds like a great idea for that Mythbusters show.

    So “valve overlap” isn’t possible?
     
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  3. AModelCat

    AModelCat Road Train Member

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    Many engines will have both valves open very slightly when a cylinder is between the exhaust and intake strokes to allow for scavenging.

    https://m.youtube.com/shorts/JdOrK87u_BA
     
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  4. Long FLD

    Long FLD Road Train Member

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    Casey Ladelle has videos on YouTube blasting air into an exhaust pipe showing that the turbos doesn’t spin.
     
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  5. Oxbow

    Oxbow Road Train Member

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    Yes, but the truck he did that on was an emission truck. Appropriate for the topic of covering exhaust on new equipment, but not as helpful for the valve lap discussion unless it was done with every possible position of the valve train.
     
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  6. Oxbow

    Oxbow Road Train Member

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    I will admit that I have often wondered why turbos don't fail while parked in a 70 mph wind, yet ostensibly can fail while being hauled at 70 mph.

    That said, we still cover them.
     
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  7. ElmerFudpucker

    ElmerFudpucker Road Train Member

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    I guess they do technically have slight overlap at the end of the exhaust stroke. I was thinking more of overlap where they are both closed and the only time they are both open would be if you were utilizing a Jake break or the overhead was way out of adjustment. But there is a brief period where they can both be slightly open. But there is no way that will flow enough mass of air to spin a turbo.
     
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  8. Boardhauler

    Boardhauler Road Train Member

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    Anybody here ever seen a Detroit run backwards?
     
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  9. D.Tibbitt

    D.Tibbitt Road Train Member

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    Is the op still around? Or did u heathens run him off? :D
     
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  10. wore out

    wore out Numbered Classic

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    I’ve seen the ol 2 strokes run backwards plenty. I’ve had my mechical CAT run backwards once. That black smoke out the breathers is never good.
     
  11. Oxbow

    Oxbow Road Train Member

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    Yes, and an A model Cat as well.
     
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