2004 ram 1500 5.7 4x4, tranny slips between 1st and 2nd during hard acceleration and only have 1st, 2nd, and reverse.

Under hard acceleration the tranny slips between 1st and 2nd and once 3rd hits, the rpms just climbs like its in
neutral and truck don't pick up speed. When just driving normally in drive the tranny don't slip between 1st and 2nd,
but it shifts pretty hard. Once it gets to 3rd it does the same as full throttle, just revs like its in neutral and truck don't
go nowhere. It does this till it slows down enough to get 2nd and keeps doin the same thing unless I keep it in "2".
It's been slipping between 1st and 2nd for a few months now and occasionally it would slip when trying to takeoff
from a stop when first starting the truck and every now and then it would go in "tow mode" by itself cruising down the
highway and wouldn't go back to overdrive unless I stoped and turned the truck off for bout 30 mins. But not goin
past 2nd is a new problem. I've checked the fluid and it's good. I should add that its supercharged and pushing
400hp at the rear wheels with a 6" lift and 35" tires and a Detroit locker and I do run it in mud all the time and do run
it at the local drag race yearly where 3rd, 4th, and overdrive stoped working. So yes the tranny gets a beating and
runs hard. Is it an easy fix or have I destroyed the tranny and it's time to swap it for a Sharadon stage 2 or 3
performance transmission with a stage 2 or 3 valve body and a 3000rpm stall converter?