FYI: Who Checks Their Sink Drain Joints?
Sink drain is not on my pre check, in fact it's not on my list at all! My wife mentioned that the box of trash bags was damp, which led to me emptying out tone cabinet under the kitchen sink and finding all six pipe joints loose. It may have taken 24 years to loosen, but the water dripping was current.
Just saying that many other coaches may have loose connections that only need to be hand tightened, by a strong hand!