Hi guys, I am going to be doing this shift kit soon. I notice TransGo sells 1-2 & 2-3 accumulator pistons together. On their website they say they are more durable than the stock ones that "wear out prematurely". Do these need to be replaced? I didn't see any mention of you using new 1-2 and 2-3 pistons so I'm not sure if it's necessary. My tranny has 48k miles on it and no malfunctioning going on besides that I want to firm up my shifts.