Starting about a week ago, the latch on my back door knob won't retract into the doorknob unless I turn the doorknob. This means to close my door properly I have to unlock the doorknob, turn it, close the door, then lock it again.

If I try to just close it, the latch won't retract and just bangs against the door frame. If I try to push the latch closed with my hand, it (mostly) won't budge. If I fiddle with it enough, I am able to push it in, but usually this doesn't work.

Is this just a possible issue that lubrication will solve? Or am I looking at replacing my doorknob/lock?

  • 2
    I'd note that WD-40 is not, strictly speaking a lubricant. Grease or oil would be better.
    – James
    Commented Aug 13, 2018 at 20:08

5 Answers 5


I think a little lubrication will fix this. Try turning the knob so the latch is retracted and spraying a little lube into the hole where the latch goes. Use the little straw that comes with the spray can, and get it as far in as you can. Spray very sparingly. Then turn the knob back and forth to work the latch. See if it's working any better, and repeat if necessary. A shot in the keyhole as well won't hurt, while you're at it.

If this doesn't do it, you may have to remove the doorknob / lockset and remove the latch to apply the lubricant more thoroughly - but I doubt it will be necessary.

For the lubricant - some people agonize over what to use, I do not, WD-40 or a good quality silicone spray will be fine.


Tried lubrication but it didn't seem to fix the problem. I ended up just buying a new latch assembly and that solved my problem.


I used garage door silicone lubricant in the latch mechanism and it worked like a pro. No issues.


Bolts rarely get sticky unless something has shifted or broken. There's nothing wrong with trying some lube, but my guess is that the knob's mounting screws have loosened, and the knob has been displaced upward or downward, causing binding. I'd loosen the screws slightly, slide the knob up and down to find center, and snug the screws up again.

Lubricating may allow the bolt to move freely again, but maybe only until the lube is worn away. Better to fix the actual problem.


I think it has to do with august heat and humidity. I would tighten the screws on the hinges, frame and door, to pull the plunger away from the latch. If your door has enough give to seasonally conk-out, it should have enough give to tighten up once you put major torque on the hinge screws. WD40 can also help lower the activation energy threshold, which can make-or-break borderline operation.

Not the answer you're looking for? Browse other questions tagged or ask your own question.