Early pr & media releases regarding engine longevity for the Duramax stated that GM anticipated that the engine would last at least 200,000 miles. That's a lot shorter life span than the 400k or so most of us anticipate before having to put some serious money into our B series engines. For us snowplowers it's a given that the engine will outlast the rest of the drivetrain. From personal experience, the Dodge frames and trannys are much stronger components than those in the GM vehicles, and we've tried them all. Frame failures in 1 ton GM trucks and having to keep spare trannys just to make it through the winter - - not fun! Of course these failures associated with snowplowing. Can't speak to towing or load issues.