6.2 D oil leaks

[Ville K]

I have a ´87 R10 with leaking crank seals. Front seal started to leak and it was replaced, and the damper was replaced at the same time. few days after that it started to leak again, and it was diagnosed that the dampers surface was too rough and it had eaten the lip from seal. The damper was polished and new seal changed, problem solved. few months and rear seal started to leak, it was changed last week and oil pan seal ofcourse at the same time. Now it looked like I could have many miles without leaking oil everywhere. But two days after rear seal change it started to leak from the front seal again!
The car has only 104K miles on it, and oil+filter is changed every 3000 miles from new. It has been very cold here in Finland last week or so, and first I thought that maybe the pcv valve was freezed, but it wasnt. It doesnt seem to make pressure to the crankcase either. Anyone with any similar symphtoms?
Thanks, Ville