Transmission Slam and maybe more
 

So my 98 SC2 has around 207k miles and the auto transmission is acting up. I remedied this with some Lucas Automatic fluid, but that was just to mask the problem. I know it has something to do with the input shaft nut and/or the valve body but I am not 100%. Since the Saturn Fan forum is dead, can anyone send me a link or paste a more detailed explanation of it? And also if there are any other tips and tricks to maintain the longevity of the tranny?

We need to know under what conditions it slams before we can help you. And anything else it does that is not by original design.

Input shaft nut.
I'd like to see that.
Do you have any experience with trannys?
Your request is so lacking makes me ask,

ya I know basic maintenance, but nothing serious. Luckily my dad is a mechanic so he's teaching as we go along.

fair enough. So in 2022, I noticed weird shifts. I was told it was do for an transmission fluid change. So I took it to my dad's shop and changed the fluid and it drove perfectly. Last year I had to run arrends up to a town that was in the mountains, steep roads and such. On the way back home, I took a detour onto a muddy road. Had some fun with the traction off and in 10 minutes I left to go home. It was all good till around 2 days later, thuds and slams on every other gear was happening, mostly Reverse and 2nd to 3rd. I did another transmission fluid change and added in some Lucas Transmission fluid. After a week, it drive like new. But about a month ago, before making the original post. I swore i had issues witht he transmission again but i dont remeber what it was. I haven't used it for a month until 2 days ago, and it drove and shifted so smoothly. Ya some shifts were more noticeable then others, but still very good for a 26 year old car with 207k miles.
I honestly don't even remember why I stop driving it. It drives great now. I think I just panicked when I saw Saturn Fan shut down and losing all the info for transmission repair. I do feel like the problem with the transmission will reappear, just because of all the stories I have heard about.
I do have an aftermarket radio that the previous owner installed onto the transmission cable that is connected to the cabin fuse box. That does give me issues, car would shut off and I would have to shove the cable back into the socket but i already have a spare cabin fuse box, just need to replace it.
Also sorry for not responding sooner, I almost forgot I asked.

Please Open a new thread if the problem reoccurs.
Reverse Slam = transmission input shaft nut has backed off.