Hi all, I've done some searching but can't find a trans problem that is like mine. First of all it's a rebuilt TH-350 all new clutches and steels, valve body adjustments not really sure about everything bought it's from a buddy who bought it from a buddy deal for like 200 bucks never used. Anyway It worked fine for about 6 months and then recently reverse has become weak with a very clear whistle. Now when I mean weak it works with a little throttle but when I give it more throttle it slips completely and doesn't work until the RPMS come back down. It also shudders the car when it's in reverse and you can hear it but only when applying throttle. I can stay off the throttle and it won't shudder. Now it works great in all other gears chirps the tires under hard throttle and has great engine breaking in 2nd and 1st. So I'm really stumped on this one. Maybe someone can help?? I will provide more info if needed. I don't really think any other info is needed. Maybe tranny fluid info? Well it's full and no leaks.