That's what I always thought Sam, and there is probably some truth to that. Daddy always said it was because people wouldn't take the time it required to fix them. There may be some truth to both. What I do know is that in 1983 the company that my dad worked for bought over 40 new 3406 powered Freightliners, and sent the 5 remaining Detroit powered trucks to the shop in Alabama (where I think that they were treated as spares). I remember one Saturday the 1978 Cabover Ford pulled on to the yard to the fuel pump for fuel. The driver got out, opened the side box, pulled out a gallon of oil and started pouring it in the access on the front. Someone had lost the oil cap, (driver said it was because it was off more than on) and according to the driver no one else would drive that truck. The funny thing is, when it left Lexington it was probably the best of the 5. I said all of that to say this: I think Detroit 2 strokes much like steam engines have a lot of character, but also require a little more constant maintenance (as a general rule) than say a Cat or Cummins did.. Keep in mind most of my experience with Detroits was helping my Dad. My personal experience was mostly with Mack and Cat. So my observation may not be 100% accurate. But,I do love the sound the 2 stroke Detroit makes though. I road many a mile listening to one hum. That makes them my favorite old diesel. I would like to put a 4-71 on my M Farmall one day.