Okay honey lets clear some things up.. !
The door makes a sound when you hit the lock button right?
Yes it is a problem with the lock actuator... not the door needing any lubercating!
there is no lubercating that you can put on the lock motor or actuator to fix it.. you need to repalce it!
I had the same problem with mine! I had to replace it and now it is working fine!
I know trying to explain it to someone with out them hearing it.. is kinda hard to do.. but if you just get a new acutator your little PT willl no longer scream at you !!! LOL