How To Replace A Trailer Fender

Story And Photos By Dan Armitage

It's easy to do yourself, as long as you have about an hour, and a clever 12-year-old to help!

A dramatic tire blowout at highway speed had literally "blown out" the aluminum fender on the trailer under the boat we'd just purchased. We bought the rig for a good price partially because of the damage, for which the seller had received estimates of up to $200 to repair. I knew it was a doable DIY job and got to it shortly after the boat and trailer found their new home in my yard.

Most major trailer manufacturers offer replacement fenders, and I was able to secure an aluminum, diamond-plate-pattern boat trailer fender from Continental Trailers. Several sources also offer generic replacement fenders for a variety of boat-trailer applications, which can be ordered online or found at local trailer supply stores and at some big-box retailers. When I received the replacement fender from Continental, I was surprised at how light it was, that it wasn't pre-drilled with holes to secure it to the trailer frames, as well as how "bendable" the aluminum fender was without the support of the trailer frame brackets to help stiffen it. With the assistance of my 12-year-old son, we had the old fender off and the new one on within an hour. Here's how we did it:

Photo of tools required for fender replacement

1. The tools required for the job include wrenches for the nuts and bolts that secure the fender to the frame, a drill with a bit matching the bolts, penetrant to loosen the old hardware, and a spring clamp if you don't have a helping hand to temporarily hold the fender in place.

Photo of applying penetrating spray to loosen old nuts and bolts

2. Apply penetrating spray to loosen old nuts and bolts if needed.

Photo of removing the hardware securing the damaged fender

3. Using the wrenches, remove the hardware securing the damaged fender to the brackets on the trailer frame. Keep the nuts, bolts, and washers to reuse if they are not damaged. If bolts are hopelessly frozen, you may be able to cut them with a grinding tool.

Photo of using a spring clamp to hold new fender in place

4. Use a spring clamp, or a helping hand, to hold the new fender in place to mark the locations of holes that will be drilled into the fender to secure it to the existing brackets.

Photo of installing the new fender

5. Most fender brackets, such as these on the Continental Trailer, offer slotted holes for the hardware to allow the fender's position to be adjusted closer or farther from the frame before being secured to the brackets.

Install the new fender using the old hardware or new, depending on condition.

Photo of drilling the holes for the mounting hardware in the new fender

6. Drill the holes for the mounting hardware in the new fender.

Photo of the completed project with new fender installed

7. Finished! 

— Published: Fall 2013


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