2007 Chevy Silverado HD Duramax,Diesel Allison Transmission

If your truck is an 07 classic with the LBZ/Duramax like mine, keep it. Over the next 200k miles I expect to spend 5-10 k on repairs as injectors and other stuff wears out, but I do not expect the main driveline to wear out. If it did breakdown on the road, we do have our house right behind, so we can wait for repairs or trade then.
There are thousands of these trucks out there with many more miles than that with that experience.
The 07 classic has a higher resale value than trucks up to 3 years newer.