What type of coupler do you have? Trigger latch, A Frame, Flat mount?
It could be the flange lip on the coupler sticks out a shade to much to allow the pin to go up inside.
You are opening the pin and taking the key out before installing the lock right?
You may look into the groove that slides over the coupler lip on the lock and make sure it is clear and/or file it out a little, or grind the lip of the couple down just a bit, perhaps a 32nd of an inch...
Realistically, any couple lock will work well. They keep the honest man honest. If someone really want to steel a TT, they will get it. Even with a coupler lock in place. I have heard of guys utilizing chains and giant tow hooks.
I made my own coupler lock of sorts. I cut off the treads on a 2 inch ball and put that up inside the coupler, then I use a specific type of padlock instead of a safety pin on the latch. This way when its parked, the latch is locked and can't be opened, and when its connected to my truck the latch is locked and cant be open until I unlock it. Like I said though, if someone really wants it they will just cut the lock.
2015 White Hawk 25BHS Glacier Package
2004 Dodge Ram 2500, 5.7 Hemi, 5Spd Manual
2008 Arctic Cat M1000 SnoPro
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