Buy Mercedes-Benz SLK320 Fender Liner Or Splash Shield

Quick Overview

Quick Overview

The Mercedes-Benz SLK320 fender liner-also called a wheel-well liner, inner fender, splash shield, or wheel-house cover-mounts inside the front wheel arches of 2001-2004 SLK320 roadsters (R170 chassis). Its tough plastic panel keeps mud, stones, salt, and water from striking the engine bay, headlights, wiring, and rocker panels. It also smooths airflow around the tires, trims road noise, and helps slow down rust. The SLK has liners only at the front; the rear arches rely on factory under-seal instead. When the liner cracks or falls off, debris can damage belts and electronics, and visibility can suffer if spray reaches the mirrors-issues serious enough that similar splash-related problems have forced safety recalls on other vehicles. (Wikipedia, MBClub, Mercedes-Benz Classic Center, EverCare Protection, Grassroots Motorsports)

What It Does

Shields & Safety

A liner forms a barrier that stops grit, water, and road salt from blasting the engine, suspension, and brake lines, cutting repair costs and preventing corrosion (EverCare Protection, Durabak Company). It also damps the "ping" of gravel and quiets the cabin (, Reddit).

Airflow Help

By closing the open cavity behind the tire, the panel reduces drag and high-pressure air that can lift under the hood. Enthusiast tests show only small gains on street cars, but every bit helps fuel economy (Grassroots Motorsports).

Where It Fits

Front-Only on R170

On the R170 SLK320 the liner bolts to studs and plastic nuts around the front wheel arch. Owners report a 20-minute removal per side with a ratchet; the rear arches have no hard liners, only felt-type mats (MBClub).

Common Materials

Modern liners use flexible ABS or thermoplastic that resists rust yet can flex on impact. Earlier cars used metal inserts that corroded quickly (CarParts.com, EverCare Protection).

Signs of Damage

• Cracks, holes, or missing clips
• Tires rubbing the panel when steering
• New rattles or a flap sound at speed
• Mud or salt splatter inside the engine bay
• Fogged headlight backs or soaked wiring looms (Caliber)

DIY Replacement

1. Turn the steering wheel for access or remove the wheel.
2. Pop plastic push-pins and 8 mm screws with a trim-tool or nut-driver.
3. Slide out the old shield and test-fit the new one.
4. Re-use or replace clips; torque M6 plastic nuts to hand-tight (≈3 Nm).
5. Check clearance by cycling full lock. Most owners finish in under an hour (CarParts.com, MBClub).

Maintenance Tips

• Rinse wheel wells after winter driving to wash away salt.
• Inspect fasteners at every oil change; replace broken push-pins.
• Treat the liner with plastic protectant to slow UV brittleness (EverCare Protection).

Costs & Time

A brand-new SLK320 front liner (part 170-690-19-30 left, 170-690-20-30 right) lists around $40-50 each (Mercedes-Benz Classic Center). DIYers spend mostly on clips. Body-shop labor averages one hour, or roughly $75-150 depending on local rates (Reddit).

Environmental Impact

Keeping the shield in place lowers under-body rust, which cuts the need for steel repairs, and marginally improves aerodynamics-both of which reduce lifetime CO₂ output (Grassroots Motorsports, Hooke Road 4x4).

Fitment Details

• Chassis: R170 SLK320 (V6), model years 2001-2004
• Location: Front wheel wells; right = 170-690-20-30, left = 170-690-19-30
• Exclusions: "Without Sport" notes refer to AMG 32 models that use different brake-cooling ducts (Mercedes-Benz Classic Center).

Frequently Asked Questions

Q: Is a splash shield the same as a fender liner?
A: Yes. Terms such as splash shield, wheel-well liner, inner fender, and wheel-house cover all point to the same protective panel. (Durabak Company)

Q: Does the SLK320 have liners in the back?
A: No; the rear arches use felt under-seal, so only the front liners need service. (MBClub)

Q: Can I drive without one?
A: You can, but debris will reach wiring and metal parts, speeding rust; in salty climates damage appears fast. Replace it as soon as you can. (Reddit)

Q: How long does a good plastic liner last?
A: Thermoplastic panels often last 10-15 years unless cracked by an impact. UV and road salt shorten life. (EverCare Protection, CarParts.com)

Q: Which tools do I need?
A: A Phillips or Torx driver, 8 mm socket, trim-clip pliers, and optionally a jack and stands for wheel removal.

Q: Do I have to remove the wheel?
A: Turning the steering fully usually gives enough room, but removing the wheel speeds access.

Q: Does a new liner improve fuel use?
A: Only slightly, by smoothing airflow and stopping drag-creating cavities, but every bit helps. (Grassroots Motorsports)

Q: What fasteners secure the panel?
A: Mixed plastic push-pins and M6 speed nuts; many break during removal, so buy extras. (CarParts.com, Durabak Company)

Q: Can I patch a crack?
A: Small cracks can be plastic-welded or sealed with epoxy; large breaks usually call for full replacement. (Caliber)

Q: How much will a shop charge?
A: Typical labor is one hour; expect total bills between $120-$200 including the part and clips. (Reddit)

Q: Where do I find the part number?
A: It is molded on the inside of the old liner near the rear edge; for the SLK320 it starts with 170-690-19-30 (left) or 170-690-20-30 (right). (Mercedes-Benz Classic Center)

Helpful Resources

• Mercedes-Benz SLK-Class R170 history
• Discussion on SLK wheel-arch liner removal
• Aerodynamics chat on fender liners