1999 Ford F-150 - Leaks from transmission

1999 Ford F150 4x4, 68,000 miles. 5 years ago only on two trips to a cabin in the mountains, once I got there I noticed there was tranny fluid dripping from the bell housing, once cooled it stopped no leakage on the way home or driving. around. To be safe and I read that Ford had front seal problems, I took it to a recommended tranny shop. they said it was the seal and replaced it. It still leaked a little they recommended to change the torque converter to be safe and they said they couldn’t test it. When I picked it up on the second time up they told me that the rear main was seeping, I wasn’t happy they didn’t call me when they had it apart. its been 5 years and only 5000 miles, and after another trip to the cabin I noticed a oily stain in my driveway, I crawled under neath and pulled the rubber plug in the bell housing and there was red fluid, plus a little oil, and I know Ford had issues with some oil leaks around head gaskets but I have no signs, again the oil was red. The tranny was only down a pint at the most, I’m now again at the cabin, and have been watching it so far no leaks. The first two times I had my ATV trailer and after I had it fixed twice I had no problems till now. The last one where I noticed a stain in my driveway when I got home I had no trailer and it was all down hill and flat. I’m considering maybe trying a seal sealer to try, before I spend another $1300 bucks to change the seal again and if I do I for sure will change the rear main while its staring them in the face. My tranny is the 100 which is the larger tranny Ford used in the F150’s. The tranny shifts fine and no issue other than the leakage. Any ideas and thoughts would be appreciated, naturally after 5 years the shop won’t help the original two repairs had a 12000 mile and 1 year warranty. Thank You

Vehicles can develop leaks just because they sit. Seals dry out, shafts rust and damage seals and then they leak. In a 21 year old truck, I’d add some oil seal stop leak, check the fluid regularly and drive on.