The tranny would randomly loose 3rd,and made some grindings sounds. I decided to try and fix it on my own this time. The grinding sounds came from an exploded thrust washer,and all the needles went through the two rear planetaries. Also the the first clutch pack is burnt,because the support bolt was loose. I have it back together up to the second gear band. Used a washer from an old turbo 400,I also discovered that the 400 had a plastic spacer inside the reverse drum,and the 4l80 didn't. Since it fit I swapped it over,probably not important ?