"Six years after buying new, Duramax injectors started leaking. Was 100% covered by GM no problem, and my dealer replaced all 8 injectors ($3000+ if I had to do it myself) under GM's extended injector warranty. That's the only problem I've EVER had with this truck. I've owned about 15 trucks over the years (a mix of Fords, GM, and Dodge), and none of them has given me any serious trouble, but as for towing and driving, this one has been hands down the best. A bigger fuel tank would have been nice, but I chose a short bed 4x4 crew cab knowing I was going to have to add an aux diesel tank. A 45 gallon aux tank/toolbox combo took care of that, and I can easily make 650-700 miles pulling a 10,000 lb fifth wheel. After six years, I'm sold on the GM DuraMax engine and Allison transmission!"