I was reading the wikipedia page on the Chevrolet C/K trucks and came across this passage, emphasis mine.
While all other C/K pickup models were dropped by 2000, the C3500 HD was produced until 2002 due to fleet demand. In the brochures it is referred to as Sierra Classic/Silverado Classic. There were two engine choices; The 8.1L Vortec Big Block replaced the Gen VI 7.4L Vortec Big Block and the venerable 6.5L Turbo Diesel.
While the 6.5 diesel might be somewhat reliable, but everything I have ever heard about them at best is “adequate”. Venerable I would reserve for engines like Ford’s 4.9 or 7.3, or Cummins 5.9, or if you want to stick with Chevy the 454 or 350, but definitely not the 6.5 diesel from the ‘90s.
Now if you’ll excuse me, I’m going to go day dream about square bodies