The 48Re is an amazing transmission design. It is basically a 727 with OD. I had mine upgraded when I had it rebuilt. The fist time I took my son for a ride in my truck after the rebuild he asked why don't they make them like this from the factory? I told him money.
With a few upgrades they are great for towing. With all the good stuff they can hold 1500 hp or more. Some of the other brand diesels put a modified 48RE in their truck when they build extreme power because it is the strongest built modified diesel transmission.