Replacement Lock Set for Sears X-Cargo X-Treme Roof Box

Published 08/13/2025

Question:

Will any Thule lock core fit this if I drill out the existing one?

asked by: R

Expert Reply:

Hey R, thanks for reaching out! *UPDATE IN COMMENT SECTION BELOW*

What I've been seeing is that the Sears X-Cargo boxes use the style of lock that matches with the Thule Kit # SR03807 and Locator # TH03808 so you'll need to go with these parts as opposed to a standard replacement Thule lock core.

Did your old lock break or get damaged?

expert reply by: Jon G

Thule Lock Core for SportRack and Sears Cargo Boxes
(click to enlarge)

8/13/2025

The lock core on my xcargo extreme does not look like that. The key broke so I am just going to replace the lock

Jon G.

8/13/2025

@R Thanks for the additional insight that you have the X-Cargo X-Treme. I looked around, and it does use the newer Thule lock cores so you'll be able to replace just the core. The lock will likely need to be drilled out since the key broke off inside the cylinder, but I do recommend checking your owner's manual for any disclaimers about drilling because I saw some hints at that online. To replace the lock you can use the Kit # TH450200. How are you planning on removing the lock?

8/13/2025

@JonG the key actually just broke but isn’t stuck inside but the key cannot be removed when it’s unlocked to use the blank key to pull it out. Do you have recommendations on how to best drill it out?

Jon G.

8/13/2025

@R Very carefully. In all seriousness though, you'll want to get a cobalt or tungsten carbide drill bit for this. Drilling out locks will eat up that metal so getting something that can resist wearing down will better serve the purpose. Worst case you can also ask a locksmith to remove the lock core for you as well.