Welcome, Scatershot - If it were me, I wouldn't be in a big hurry to replace the cables, until you have inspected them that is. There's no reason why a cable would break unless it shows damage such as rusting or fraying. These problems WILL show up during an inspection.
The likely place where the cable might be damaged is where it is under tension over a pulley. You will see most of the cables with the top up, so raise it. Then, crawl under the trailer and with a good light, inspect each of the cables as far as you can see. You'll be able to see the entire length of eadn cable as it extends across the bottom of the trailer and at least part way up the sides.
Now, inside the trailer, unscrew the trim board on top of the lower half. Start with the curb side, it should be easiest. There will be several screws holding that board in place and they are easy to remove. Once the trim board is off, you will see two of the four upper pulleys and the cable as it loops over the pulleys to attach to the lower edge of the upper half. This is probably the area of greatest strain, so check it carefully and use a flashlight to see as far down the cable as possible. (No rust or fraying? In my opinion, there's no reason to replace them.) This is also how you gain access to lubricate this section of the cables and the upper pulleys, so remember how you did it.
Now, the street side may need two upper trim boards removed (mine does). One has easy access but the other may need for you to use a small, right angle screwdriver to get the board off. Again, though, the inspection is just the same and this is how you lubricate them too.
As far as replacing them, if you have to - a pdf that describes the process can be found in the first post here:
http://www.hilotrailerforum.com/f61/...justment-5875/
Good luck!
- Jack
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