Installing trailer balls and switch balls is a relatively simple process as long as you have the correct ball size for your receiver hitch. The receiver hitch is made up of several parts: a ball on top, a long, cylindrical threaded shaft, the lock washer, and the nut, which keeps the ball secured on the receiver's ball mount.
First, insert the shaft into the receiver hole so the trailer ball is facing upward. Place the lock washer and the nut onto the bottom of the shaft, and then move them up all the way so that they touch the ball mount. Now, screw the nut on very tightly, and keep the ball on top from moving around too much. One way to do this is to grip the ball with a pipe wrench or a large set of pliers. Then, use another wrench to tighten the nut on the bottom until it's locked in place. Every time you tow, make sure the nut and washer are securely fastened.
There are many different types of switch balls. Usually, these have locking pins or grooves inserted into the shank that allow you to unlock the ball from the rest of the unit [source: TrailerHitches.com]. After unlocking the ball, you can swap it out with a different-sized one in order to fit your towing needs. Many switch balls come with multiple ball units included, so you don't have to worry about finding a new ball that fits. Remember, it's very important to install the ball properly, and to have one that's the right size. That little metal ball bears the weight of your 10,000 pound boat, so it's not something to mess around with!
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