If it works don't fix it! I should have remembered that but.......
1983 300TD running fine, time to change the tranny fluid and filter.
I also drained the torque converter while I was there.
Put 3 quarts in, start to let the converter fill. Shut down after 30 seconds.
Filled until at the lower mark of the dip stick (approx. 7+ quarts total).
Car runs fine all day yesterday. Car runs fine today until.....
After a 30 minute drive I go to park and put it into reverse. The trans slips and it makes me feel like I'm backing up a steep hill! No accelerator input makes the car come to a dead stop.
When I get back home I notice a puddle in the street from where I parked last night but nothing under the car now. If I pumped out 7 quarts there would be a hell of a mess on the undercarriage of the car and there is not so....

Has this happened to anyone before?