Duramax concerns

[Newbie_101]

Hey guys,

I'm new to the forum, to trucks for that matter. I'm in the market for a 5th wheel - something around the 30 ft / 12,000 pound mark. I've done the research and have nailed the truck down to the 2500 HD. With the durmax's pulling power and the truck's all around make up, it looks like it was built with the tower in mind.

The only concern that I have is the aluminum used in the cylinders and it's durability. GM totes that it increases the engines ability to disapate heat (which does make sense), but what kind of life can a person expect (I know that they claim 200,000 miles). I am completely new to the diesel world. Gas just doesn't make sense for the application I'm looking at. Do any of you share these concerns or can anyone put my mind at ease?

Thanks for the input