Description
FENDER
Part Number: FFN4905LC
Direct replacement (cross ref) for 15-04905M001L5.
This fender FFN4905LC is the outer wheel cover that sits over the tire area and protects the truck from road spray, debris, and impact. It replaces OEM 15-04905M001L5 and is used on the left-side application it’s designed for.
On a heavy-duty truck, fenders take more abuse than most people realize. They’re constantly hit with water, salt, gravel, slush, and whatever else the road throws up. Over time, they crack, loosen, or start vibrating, especially on high-mileage fleet trucks.
It’s not a cosmetic piece in real-world use, but protection for the truck, surrounding components, and anything running alongside it.
What the Part Does
The fender sits over the wheel and acts as a barrier between the tire and everything else around it. When the tire kicks up water, rocks, or mud, the fender keeps it from hitting the cab, fuel tanks, wiring, and other chassis components.
It also helps reduce spray onto other vehicles and keeps the truck compliant with road safety expectations in wet conditions. On top of that, it stabilizes airflow around the wheel well a bit, which helps reduce constant spray buildup on the cab side.
Common Problems This Part Solves
When a fender starts failing, you usually don’t need a scan tool to spot it, since you will hear it or see it.
Common issues include:
- Cracks around mounting points
- Loose or vibrating fender at highway speed
- Missing sections from impact or road debris
- Excessive road spray on steps or tanks
- Rattling noise from broken mounts
A lot of damage comes from vibration over time. Once the mounting points start loosening, the stress spreads and the fender starts cracking.
Why Replacement Matters
Driving without a solid fender doesn’t stop the truck, but it does start a chain reaction of problems. You’ll get constant spray buildup on parts that shouldn’t be exposed to it, which leads to corrosion and wiring issues over time.
Loose fenders also tend to rub or hit the tire if they sag far enough. That can turn a simple cosmetic issue into actual tire damage or blowout risk if ignored long enough.
Replacing it keeps debris under control and protects everything behind and around the wheel.
Compatibility and Fitment
This fender replaces OEM 15-04905M001L5. It’s a left-side specific part, so it’s important not to mix sides. Mounting holes and curvature are designed to match factory fitment.
Always compare old fender shape and bracket layout before installation.
Installation and Service Notes
Installation is straightforward but not something you rush. Old fender comes off at the mounting points, and new one goes in using factory locations.
Big thing here is alignment. If it sits too close to the tire, you’ll get contact under load or suspension travel. If it sits too far out, you’ll get extra spray and vibration.
While replacing it, check wheel studs, brackets and mounting hardware. A lot of fender failures actually come from weak or rusted supports, not the plastic or composite piece itself.
Use Case
Used in collision repair, fleet maintenance, and general body replacement work. Especially common on trucks that run long highway miles in wet or salted road conditions.
About Us
We’re a family-owned group of Peterbilt dealerships dedicated to getting you the parts you need quickly and affordably. Whether you’re looking for Paccar OEM parts, reliable aftermarket replacements, or popular upgrades like seats and filters, we make it easy to keep your truck running and on the road. If you don’t see what you need online, just give us a call or send an email — chances are we can get it. We pride ourselves on fast service, fair prices, and being a partner you can depend on when downtime isn’t an option.
