Today on This Old Trailer we are going to install a brand new coupler using part number 2836AT from Master Lock. This is going to be a three inch wide coupler on it and in between here is going to be three inches wide and it is going to use a two inch ball. The first steps involved are to remove the old coupler. It has been on there for awhile. It is rusted so take a couple of wrenches to it… see more >