Sunday, October 2, 2022


Ask Dave: How can I tighten up my RV’s lock mechanism?

Dear Dave,
The deadbolt lock (top lock on the door) is sloppy and I have a hard time locking and unlocking it with the key from the outside. What can I do to tighten up the lock mechanism? —Bob, 2007 Fleetwood Fiesta LX

Dear Bob,
From what I can find online, it looks as though your locking mechanism is an all-in-one door lock and deadbolt manufactured by Trimark®. We used these for years at Winnebago and the deadbolt latch would often get loose or “sloppy,” as you described, due to the wear of the pins that hold the metal plate that is attached to the deadbolt. This is a sandwich design and can be taken apart. Here is the diagram from the Trimark owner’s manual.

Notice the three pins, two to the left and one to the right of the mechanism. If memory serves me correctly (and I’ve been taking Prevagen, so I have a 50/50 chance), I believe they are a riveted-type connection. You can tighten these up by taking a punch and tapping it in the open side of the connection.

This will tighten it up. However, being hard to turn is due either to the mechanism binding at the key connection or the deadbolt seated tight against the striker plate on the door jamb. Does it work freely with the door open and just turning it back and forth? If yes, then it’s an adjustment at the striker.

I’ve had to adjust several of these and I typically use a black marker to “paint” the deadbolt and run it in and out several times. You will find the black marks scrapped off where it is rubbing. Then you can adjust the striker in or out, up or down, or you might need to adjust the door.

It could be a key and housing issue

If the deadbolt is easy to turn with the inside small handle, then it’s a key and housing issue. You might be able to clean it out with some CRC lubricant or 3-IN-ONE Silicone Spray. Otherwise, you can take it to a locksmith to fix the tumblers. Most of the time it is less expensive to just install a new lock. If the lock is difficult to turn with both the key and inside handle when the door is open, then you can pull the assembly and clean everything.

Also, take the lock out of the door and make sure that something did not fall into the cavity. I have seen a couple of times that the insulation of the door broke loose and fell down into the mechanism and made it hard to open the door.

Maybe change the lock mechanism

This might be a good time to replace the locking mechanism with a keyless system like the RVLock. We just completed this on a 2015 Thor Challenger. It was easy and the owner loves it! Here is a photo of the original door lock. Yours is probably more vertical or taller.

We changed the lock as they had locked themselves out during one of the camping trips. I’m not sure how the entire story went, but they somehow pried the door open and bent several things, then tried to fix it with a Dremel. We took the old lock out, and here is what we had:

This is a little hard to see; however, it is the pin for the deadbolt and it was sticking against the insulation and fiberglass inside the door. This could be what you are experiencing. We had to get pliers to move it slightly and a flat head screwdriver to bend the lock mechanism to get it out.

The new lock fit perfectly. It just had a little different “footprint” than the old one, and I thought it was odd that Thor painted the rig with the lock on. RVLock has a backing plate that covers up most designs.

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Dave Solberg is a leading expert in the RV industry and the author of the “RV Handbook.”

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1 month ago

My Trimark (same as the one in the diagram) still works good but I can’t keep it tight on the door no matter how tight I get the three screws. After a few door openings from the inside it starts to move a little and that puts the deadbolt out of alignment with the hole in the door jam. Any insight as to why it won’t stay tight?

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