[seabrookmx]

The original castings were pretty poor in the 6.2 and 6.5 and lots of them crack at the crank webbings. This is supposedly fixed in the AM General blocks. They were common work trucks in the PNW (forestry, mining) but while you see the old Cummins or Ford IDI's around still the "Detroit"'s (no relation to the 2 stroke Detroit or Series 60) are quite rare. My family still has an early mechanically injected 6.5 that's held up OK though (~300,000km on it).

[frompdx]

I'd say that 6.5 as plenty of life left. My 6.2 is pushing 400,000km.

[bluGill]

the 6.2 and 6.5 are good engines - but dodge has the cummins and the ford powerstroke (other than the 6.0) are a much better engine and so they get a bad reputation.

[seabrookmx]

The 6.0's problems are solvable. It's the 6.4 you really need to avoid.

[blankx32]

Came to say 6bt aka the 12 valve must be a contender