My tranny isn't slipping yet, but I have a smarty on the way. I have a couple of questions about the upgraded 48re. When most companies upgrade the 48re do they put new clutch drums in, use stock drum, or modify the stock drum to hold the extra clutches? Besides torque converter, valve body, and shafts, what else do they upgrade? Do they modify anything else on just standard upgraded transmissions? Who makes the best 48re? I just like knowing as much as I can about what I am about to buy befor purchasing.