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SlowBro's avatar
SlowBro
Explorer III
Feb 15, 2015

Lock for a Shelby 5104 coupler

What I can't find is what are the preferred coupler locks to use that fits through the latch holes on a Shelby 5104 coupler, something that doubles as both a snapper pin and a security device when not hooked to the tow vehicle.

I found this old thread which describes and shows this coupler in great detail. Lots of pictures and description. Unfortunately there does not seem to be any way to reply to that thread so I must start a new one.

I tried this Master Lock and it physically would not fit. The shoulders of the coupler rise too high and it won't go into the hole.

I bought this lock but it looks like it's so wide on the coupler. The coupler hole is almost 7/8" wide but this is about 2" wide, which means there is lots of exposed shaft for someone with a good hacksaw to get at it. I'll try it and update with my results.

I saw that Shelby has some coupler locks on their site but I just am not clear from the descriptions which will work with this coupler. I'll try to contact the company Monday or Tuesday.

Does anyone know for certain which lock is best to use?

33 Replies

  • Hi,

    I 100% agree that when towing you want/need to have the coupler pinned or locked closed.

    That said, I pin mine.


    I do have a long shank Master Pad lock in the camper that I have 3 of them keyed alike. I use 2 of them on my generator cable and the other on the bicycles.

    Here is a quick hit on a similar one. Mine came in a set of 3.
    Master Long Shank lock

    I use those 3 locks for multiple things on the camper from time to time.

    As far as camper theft, just locking the coupler will not slow down a low life from stealing your camper. If you have a 2 5/16" coupler like many campers do, they can steal the camper with a 2" or 1 7/8" ball and haul it off to later cut off the lock and use a 2 5/16".

    For security, I use this one. It works with that Shelby coupler
    Master Ball Coupler Lock

    The ball coupler types of locks slow the low life down, but if they want the camper bad enough, even these will not stop them. If there are a lot of campers around to pick from, using a ball coupler lock may deter them to move on to easier picking.

    If you have an old tow ball, cut the thread shank off of it, put it in the coupler and lock the coupler. It works as good as the store bought ones.

    Hope this helps and good luck

    John
  • I have 8 different places around the house and on my trailers that use padlocks that are keyed alike. Just use the padlock, of your choice, that fits the hole.
  • That is the coupler I have on my trailer and I simply use an old fashioned Master combination lock. It has been on there for 11 years and still opens fine. You don't have to use a "coupler lock" but just any lock that will fit will work.
    Barney

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