There's no g in cummins. Get that part straight before you do your google searches.

The early 24v engines had some with an engine block issue. Google dodge cummins Brazilian block.

Also the 24 valve trucks had a notoriously poor vp44 lift pump. When the lift pump goes you can keep driving but it will kill the injection pump. If you get one of these trucks, a pressure gauge for the lift pump is a wise investment.

If you're going for an older truck with the 12v mechanically injected truck or a newer truck this won't be an issue.

Every Cummins truck with the auto I've seen has puked the transmission by 200k miles so find one thats already been rebuilt.