I've been a truck nut all my life starting as a little kid, my Grandma lived near a main road and a trucking company wasn't too far away with Mack B and F models passing by all the time. I always ran to the window or roadside to watch the trucks drive by when I heard them. As I got older I learned of the different engine manufacturers and got to where I could identify the engine brand in a truck by the sound it made. The early Detroit engines were easy to identify, the differences between Cat and Cummins were much more subtle. Mack had its own unique sound as well.
Those engines always had an exhaust growl to them regardless of how well muffled they were. I think it's safe to say that Cummins became the most popular engine over time and I became very accustomed to hearing them, especially pulling away from traffic lights. I drove trucks both in construction and freight for 20 years with each of the engines I mentioned too.
Lately though in the newest trucks I'm hearing something entirely different. When they leave a stoplight I really don't hear any exhaust at all, just a God-awful racket coming from under the hood. The best way I can describe it is sounding like an old baling machine in need of greasing! I'm hearing the same sound between different brands of new trucks so I guess its a result of engine design. Had I heard this sound in earlier trucks I'd have guessed there was a terminal problem about to implode. I've never heard a smooth running machine sound like this without having a major problem.
So I'm curious. Those of you who work in the industry, can you explain to me what's going on here? What part of the engine is making this awful noise and why don't they self-destruct?
Those engines always had an exhaust growl to them regardless of how well muffled they were. I think it's safe to say that Cummins became the most popular engine over time and I became very accustomed to hearing them, especially pulling away from traffic lights. I drove trucks both in construction and freight for 20 years with each of the engines I mentioned too.
Lately though in the newest trucks I'm hearing something entirely different. When they leave a stoplight I really don't hear any exhaust at all, just a God-awful racket coming from under the hood. The best way I can describe it is sounding like an old baling machine in need of greasing! I'm hearing the same sound between different brands of new trucks so I guess its a result of engine design. Had I heard this sound in earlier trucks I'd have guessed there was a terminal problem about to implode. I've never heard a smooth running machine sound like this without having a major problem.
So I'm curious. Those of you who work in the industry, can you explain to me what's going on here? What part of the engine is making this awful noise and why don't they self-destruct?
