Hello - great questions. I have owned seven Duramax/Allison powered trucks, one was a 2004 C4500. Alot has to do with what you are towing, how far you tow it, and alot of subjective personal preferences.

As far as the 250K, I wouldn't be afraid of the truck - but would be very curious to know how many sets of injectors it has gone through. I bought my truck with 25K, and by 135K, it had already needed TWO SETS, luckily covered under warranty.

With a set of 8 new sprays running ~5K, it is a major consideration when buying a high mile used Duramax.

So...
  • What is 8th digit of truck's VIN (identifies engine family)
  • How heavy do you tow
  • How far do you tow
  • What is most important to you in a tow rig (ride, mileage, braking, look, etc.)