I had a 2000 model 5 speed 24V ram 2500, it was also a 53 block. The truck had 200,000 miles on it when i sold it and never an issue with the block. I think its safe to say if it was a problem it would have shown up by now. Seems like the ones that had issues showed up pretty quick. It was a great truck, and towed like a beast with 4.10 gears, an edge programmer, airdog fuel system, S&B airbox, and a upgraded clutch.
Matt