96 4wd Blazer LS 4l60e. Numerous trans issues. At WOT transmission wont shift to 3rd, shifts out of 2nd at normal time engine revs up and there's a rattle. Also rattles occasionally at statup and going into R. 2 months ago I got a 1-2 solenoid code, due to time and money I drove in limp mode for a week. changed all the solenoids and this issue followed. On one of the solenoids I spun the 1-2 accumulator out of the way. If I broke the spring would this have caused this problem? I was planning on replacing the 1-2, 3-4, and forward accumulators, also the 1-2 servos. And new springs for all. Is there a separate 3-4 servo? Would a broken spring cause a rattle? Would this fix my issue or should I rebuild the whole thing? Are there any special tools required for a rebuild? Trans fluid is full and clean. Any ideas? When in 3rd it will hold at WOT just wont shift there at WOT. Replaced Catalytic converter last weekend. Could one of the new solenoids being bad cause this?