Pre 99 2500 6.5 Or 99-06 1500 5.3?

[hoorders]

Im debating on getting rid of my 2000 silvy 1500 4x4 z71 which has the 5.3 in it for the old body style 2500 4x4 with the 6.5 diesel.

 

I don't know much about diesel engines and was just wondering if anyone could share some info on those trucks.

 

Is the 6.5 going to have more grunt/capicity for towing and is it going to be any better or worse than my 5.3 on milage.......and what about over all reliability of those 6.5's?

 

Thanks very much...........