[{tpc}]

I feel like the biggest difference between the two vehicles has to be gear ratio, not necessarily "power". But a quick google lead to some complaints on certain silverados with the 5.3 and 3.08 ratio that had to do with a lack of power.

How hot did the tranny get? Do you have the auxiliary trans cooler that mounts up front directly in front of the radiator? I believe all of these trucks have a built in trans cooler, but not all have the additional one up front, which is a huge help.

Also note that because the built in cooler is cooled by the engine coolant, if your engine temps start climbing above 210, your trans temp is going to climb as well. Thats is why I think having the additional cooler up front is such a big help because that is being cooled by direct airflow.