i just complete my suspension upgrade. and noticed a vibration in the rear end (was told it was the dispus cupler on the rear of the driveshaft, drive it its ok) so i did.getting worst though, then tranny started to shift hard. i was told to check to see if the fluid in the overflow had tranny fluid in it and it does, new info.. install seperate tranny cooler flush system (coolent,tranny) and this may fix the problem worst case trannys shot. replace it. does this sound about right? has anyone had this problem, or had to do this type of work to there x, and what kind of $$ do you think were talking about?