Trunk Latch

The trunk latch on my 2009 Mercury Marquis is malfunctionng. It sometimes will close OK, then at other times it will not, and then it requires that I hit the trunk button on the car remote button to make ithe latch close. I have tried WD-40 on it, but it still does not work OK. The Ford dealer said that I need a new latch installed at a cost of $265! Can I buy a new lacth (ca. $45) and install it myself, or does it require any special tools or a reset of the car’s onboard computer?

I tend to think it’s more likely an adjustment of the latch or striker that is needed. Do they look like they line up properly at the moment of closure? When you have the trunk open, can you tell if the latch on the trunk is in the open position to be able to accept the latch (striker) attached to the body? It sounds like it might be in the closed position, so the trunk bounces off of the striker. If you do need a new (used) latch, you shouldn’t need to reset anything, especially if the fob makes it click as it should. The latch itself has no brains.

Ford of late has been making pathetically weak latches. I’ve now replaced all four door latches on my 2000 Explorer, and the hatch latch was replaced before I acquired it. I don’t understand why the quality has gotten so bad. I have 2 20+yo Toyotas that still have the original latches and my classic '62 Thunderbird has it’s original latches.