How To Remove Rusted Trailer Hitch Ball

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You need to switch to a different-sized ball to tow your buddy’s trailer, but the old one won’t come off. How do you remove a rusted trailer hitch ball?

Removing a rusted hitch ball can be painful, but you should begin by spraying a liberal amount of WD40 (or other rust-inhibiting fluid) near the connection points. Then use a rubber mallet to knock the ball mount free. You may repeat the process until the ball loosens and slides out.

Every day, millions of Americans hitch their trailers to a truck and go about the business of towing stuff. Whether it is lawnmowers, furniture, a camper, or a boat, these tow warriors depend on their hitch and ball to work. Unfortunately, these components are also exposed to the elements daily, which means that they can become hunks of rusted metal. Over time, the rust can be a bonding agent between the receiver tube and the ball mount or lock the mounting nut for a hitch ball. Either way, knowing how to remove a rusted trailer hitch ball is essential. So what do you do? What is the best way to free a rusted ball mount, so you can tow the trailer your buddy is renting? Let’s examine some ideas and see if we can’t get you back to tow-warrior status.

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What Produces Rust?

Rust is a natural byproduct of metal being exposed to moisture. The iron (FE) in metals oxidizes, acting as a corrosive agent. Over time, the rust worsens (the oxidation increases), creating deterioration of the structure of the metal. At times the rust is so severe that the rust acts as a bonding agent between two separate pieces of metal. This situation happens when a receiver tube rusts with a ball hitch or trailer ball rusts with the mount.

How To Remove Rusted Trailer Hitch Ball?

Here are some steps to removing a rusted trailer hitch ball.

Gently Tap the Hitch

You must tap the hitch receiver with a rubber mallet to remove as much surface rust as possible. The hard tapping will loosen any excess rust that might make penetrating the bonded area more difficult. If you hammer lightly on the hitch or ball without damaging it, you can get the WD40 directly to where it needs to go.

Spray WD40

Take a can of WD40 or another lubricant (Liquid Wrench, Free-All) onto the affected area. You may have to use a spraying straw to concentrate the penetrating spray exactly where needed. Tap the hitch/ball again to help the lubricant get into the grooves between the rusted ingredients. You need to follow all manufacturer’s instructions and wear safety goggles to prevent the spray or bits of rust from getting into your eyes.

Tap With A Hammer

This harder tapping will likely break the bond of rust built up over time. You may have to reapply more penetrating spray and tap with a rubber mallet before the bond becomes broken. Eventually, the liquid and the vibrations from the hammering will loosen the ball mount from the receiver hitch so that it can slide out.

How To Remove a Rusted Hitch Ball From A Mount?

If you can get the ball mount out of the receiver tube, you can use a sturdy vise to help you in this task.

Clamp The Ball Into A Vise

Gently place the hitch ball into a vise and clamp it tight. Make sure the locking nut extends out of the vise.

Tap Off Surface Rust

Use a rubber mallet to knock off as much surface rust as possible. In this situation, the thread of the nut and bolt have fused. This is the area that you need to try and attack. Hammer off the rust and wipe clean.

Apply The WD40

Apply a liberal amount of penetrating fluid to help soak the rust and lubricate the nut. If you tap the bolt after each spray, the vibration should help the liquid penetrate the threads.

Fasten A Wrench To The Bolt

Fasten a large wrench (a big pipe wrench or large crescent will do the trick). Apply as much brute force to see if the nut will turn. Suppose it doesn’t apply more penetrating fluid and try to work the nut free. (For stubborn nuts, you may need to hit the handle end of the wrench with a hammer in the direction of the nut loosening. The force of the downward blow will break the rust bond and begin unscrewing the nut. Once the nut is loosened, it usually has enough freedom to come off completely.

Will Using Heat Help Loosen A Ball Nut?

Another method to remove a rusted trailer ball is to apply heat on the nut with a blowtorch. Since heat expands metal, you want to heat the nut, not the bolt. The threads on the nut should loosen, making it easier for the bond to break free. Remember to use safety glasses and take precautions when using a torch. Clean the hitch ball of any penetrating fluid or grease that may have been applied previously.

(Please note - do not use an open flame anywhere near penetrating sprays like WD40 as they contain chemical compounds that are highly flammable).

How Do You Prevent Rust From Forming On A Hitch Ball?

Using grease as a protective barrier is the best way to prevent corrosion on a hitch ball is to use grease as a protective barrier. Applying grease to a trailer ball should be done a few times yearly (every six months or 6,000 miles at a minimum). Grease will create a barrier between the hitch’s metal and the elements, but the dampness of the grease tends to attract dirt and grime from road surfaces. Even though it is messy to work with the grease, the protective barrier will help your hitch ball last longer and makes it easier to work loose if you need to change ball sizes. Coupling and uncoupling your trailer is much more manageable. (The coupler slides off of the ball with ease due to the lubricant).

Many truck owners cover their hitch balls with a plastic bag or cover to help limit the exposure of the ball to the elements. There are millions of different covers that you can purchase online, so you should have no limit to finding something that fits your personality.

The best way to prevent rust is through regular maintenance. Keep your tow vehicle clean and washed regularly, and examine the entire hitch for signs of rust. Remove the hitch ball and mount, when it is not in use to keep it from rain and other outdoor elements.