Fenders are the body panels that surround a car or truck's wheel wells. Because they contribute so much to the overall shape and look of your vehicle, it's easy to forget that fenders serve an extremely valuable function - keeping water, snow, dirt and debris from being flung upward from the tire treads and onto the body or glass of the vehicle.
When you buy a truck off the showroom floor, it will be equipped with wheels and tires chosen by the manufacturer that have been sized to fit completely within the fender wells. Enough extra space in those wells will be included to allow factory-size tires to articulate (move up and down) to the full extent your suspension design allows - without rubbing against fenders or other components.
When you mount bigger tires on your truck, their larger diameter and circumference poses an immediate problem when it comes to clearance. This issue can be eliminated by raising the overall height of the body through suspension lift kits, and/or by creating larger openings around the fenders.
These larger tires are also wider - often to the point where they protrude from the wheel wells outside of the fenders - bringing back the issue of flying debris that can cause property damage. In some jurisdictions, such unshielded tires can actually violate vehicle equipment laws and be subject to police fines.
At CARiD, our fender flares are one of the more popular exterior accessories for trucks, SUVs,and Jeeps. They add a sense of style and substance to your ride, and also serve an important function: should you install wider wheels and tires, our fender flares continue the desired "look" by maintaining fender coverage over your new rubber. (Read more at our Helpful Article Fender Flares Give Your Truck Style and Protection.)
Note that most of the fender flares we sell are designed to mount without cutting or drilling (we invite you to read our related article No-Drill Fender Flares Are So Easy To Install for more details). But if you're looking to install really huge tires, or simply want the most aggressive look you can get, the best option might be to cut your fenders, and then install fender flares that are sized and proportioned for the larger openings you'll create. In this article, we'll cover the how-to steps involved with cutting into your fenders.
Note that our instructions are intended to be general in nature. Should the cut-out flares you've purchased contain specific installation instructions, those would take precedence. This type of installation is recommended for the more experienced installer. Should you have any doubts about your abilities, please seek out the assistance of a professional.
Steps For Installation Of 'Cut-Out' Fender Flares
Choosing a good cutting tool is really the first step in the process, whether it's electric or powered by compressed air. Tools with a rapidly moving back-and-forth saw blade tend to cut more easily through thicker steel, while rotary cutting wheel tools tend to give the user a greater degree of control. Naturally, you'll want to protect your eyes with safety glasses, and possibly a mask or respirator.
Step 1: Check What May Be Hiding Behind Your Fender
Before anything else, it's important to take a peek inside your fender well to inspect what may be hiding on the other side of your fender. Electrical wiring harnesses, fluid reservoirs, pressure lines, fender braces, and evaporative emissions components such as charcoal canisters are some of the things auto manufacturers tuck inside fender wells to save space under the hood. Temporarily detach any items necessary, and suspend them with a wire hanger for support.
Step 2: Detach And Pull Back the Wheel Well Inner Liner
Remove any factory fasteners that secure the wheel well liner to the vehicle's fender. They may be plastic tabs that pry loose, or they may be simple screws.
Be on the lookout for any fender support braces that may be mounted to areas you plan to cut away. These braces keep the fender positioned correctly and secured to the vehicle firmly. Relocating any fender braces will be worth the effort. If they can't be bolted and re-bolted easily, welding may be required after cutting. Hire an experienced body shop to position any fender support pieces out of the way if you don't feel comfortable doing so yourself.
Step 3: Mark Your Cut Lines
Your cut-out fender flares will come with their own instructions, so follow any guidelines not mentioned here by us. Because the flare pieces are vehicle-specific, they are sized and contoured for your specific make and model. The makers of the kit will most likely provide a template or cutting guide to show you where you'll be cutting on your truck. But regardless of how you go about deciding where to cut, use a marker or masking tape to clearly define the lines; either of these will make cutting that much easier.
Step 4: Make Your Cuts
Cut along your pre-determined lines that you made on the sheet metal surface. Once you've got the cut started, continuing it won't really be that hard. Another option is to cut slightly less metal away than you marked off originally, then cut a series of perpendicular slices into the metal. Using your hands or a pair of pliers, fold these slices up and back into the fender well. This cut-and-fold method creates an opening that's just as large, but allows the sheetmetal to retain more of its original strength. Before folding the pieces back, we recommend spraying the edges of these newly cut areas with primer paint as discussed later in Step 6.
Step 5: Trim Away Any Excess Metal Behind The Fenders
Once you've cut away or folded back your fender metal, you may come across additional braces behind the fender that need to be cut back as well. Mark and cut them off in the same fashion as you did with your fender pieces.
Step 6: Apply Primer to Newly Cut Or Drilled Metal Areas
To prevent corrosion that will quickly set in on newly exposed bare metal edges, mask off the areas of the fender surrounding all of your new cut lines. Spray bare metal areas gradually and repeatedly with primer until they are coated evenly. This also goes for any sheetmetal holes made with a drill to serve as anchoring points for the flare pieces.
Step 7: Re-Install Your Wheel Well Liner
Depending on the position of your vehicle's mounting holes for the wheel well liner, you may be able to re-use the same holes. However, if you've folded or cut away the metal where the holes were, you'll need to drill new ones. Look for applicable areas that are practical to drill into, then do so - drilling first through your well well liner, then the vehicle metal. Once you've drilled, apply primer paint to the new holes to inhibit rust, then secure your liner in place with original tabs/screws. If it's easier, you may simply want to use new screws or other fasteners.
Step 8 - Mount Your Fender Flare Pieces
Once you have your wheel well liner in place, you're ready to install your cut-out fender flare pieces. Follow the instructions which were included in the kit, because they may be designed to attach via drilling, or with 3M double-sided adhesive tape. If drilling is the specified method, your piece will be equipped with holes at pre-determined points for your specific truck. In other words, the drilling locations will be at points where there will still be something solid to drill into after your fender modifications.
Some cut-out fender flare kits use double-sided adhesive as a sole method of attachment, or as a secondary reinforcement. If your kit comes with it, that's a good thing. Automotive adhesive tape is very durable in all weather conditions, and it adapts well to extreme temperature fluctuations. If you'll be using tape, it's extremely important to clean vehicle areas with alcohol, or better, wax and grease remover, where the tape will be applied. The adhesive strip will come already attached to your fender flare, with a backing strip that's peeled off during installation.
First, line up a fender flare on your vehicle body in its appropriate location. Follow the provided specific instructions if necessary. Use masking tape to mark the exact position, once you're satisfied with it. Peel off about two inches of the backing strip on both ends of the adhesive tape, and press the flare piece onto your vehicle. Adjust as needed. When it's lined up, slowly peel the rest of the backing strip away and press firmly as you go. It will adhere quickly, but avoid washing the vehicle for 24 hours. Take any other precautions that the included directions specify.
Once you have your cut-out fender flares installed, your vehicle will look like the fully-formed all-terrain climber you know it is. And look how much better those beefy wheels and tires look under those new flares!