I had two original gaskets for the lid, both leaked and both were well used. Making a new one for the lid was not difficult. The cap and the piston seal just flat out fell apart. The lid seal, if not used and abused I don't think matters how old it is, the cap and piston seal even " as new in box " are subject to aging.

Quote Originally Posted by mgb74 View Post
I sold an "as new in box" Unidrum a while back (it came to me with a bunch of other stuff). Mine had a few spare gaskets in the box. Were you using the "factory" gaskets and still leaking?