Yeah, well these things happen. You will notice that the platform the Filtrator cartridge sits on has a row of holes on I think the left side as you face it. Sorry I don't remember, I have to replace both heating elements in mine before I put it back into use so I have not had the cartridge out in a while. Those holes are prone to clogging with wet linty slurry. I found that my Filtrator dryers had to be "leveled" slightly lower on the side with the holes to ensure proper drainage.
Then there is the old material sealing the bottom corner seams of the outer tub and the foam against which the Filtrator cartridge seals at the back of the dryer. Any and all of these are potential sources for leaks. Loads not spun in a Unimatic machine will have much more moisture for the system to condense which can make leaking worse.
Something vulnerable in these machines which you cannot replace are the little rollers that support the front of the drum. They are mounted on the back of the panel that surrounds the drum opening behind the door. I don't know which model you have, but if it is one with the small door, you have to be very careful in handling the removal and installation of this panel because you can break the door switch. The rollers have a rubber coating and if the lubrication in the bearing in each roller dries out, they will not turn smoothly which will tear the rubber. I lube mine at the start of each drying season since you have to remove that inner panel to do a good cleanout of the lint in the outer tub. You will also have to clean out that area if you have to reseal the seams if they are leaking. I won't go into all of the details of the process because you might have already done it.
