I'll go first, the above Cadillac 4900 (and probably some other engines in the series) put the can right over the back of the transmission on a brittle aluminum filter housing. If some yahoo overtightened the filter or didn't lube the o-ring then there was a good chance you'd break the filter housing trying to get enough leverage to spin it loose. Once it was loose it drained onto the top of the transmission and ran down the back of it and around the lip of the trans pan. Oil stayed in the trans case ribbing too. Total mess, terrible location. Thankfully we don't see these anymore.