Hella 355111282 Vented Disc Brake Rotor, 300mm

Hella's 355111282 is a vented, one-piece disc brake rotor built to the standard the Hella name carries across braking hardware. It measures 300 millimeters across the outside diameter, runs a 19.90 millimeter nominal thickness, and stands 66.10 millimeters tall at the hat. The wheel bolt pattern is 6 x 120 millimeter. It's cast from gray cast iron and finished with a zinc coating to hold off surface rust. This one ships as a single rotor.

The vented design is the part that matters most when you're actually leaning on the brakes. Internal vanes run between the two friction faces and pump air through the rotor as the wheel spins. That airflow carries heat away from the pad contact area, which is exactly what you want on repeated stops, long downhill grades, or any time the brakes stay busy. Heat is what fades a braking system, and a vented rotor sheds it far better than a solid disc of the same size.

One-piece construction means the hat and the friction ring are a single casting. There's nothing bolted together to loosen or introduce runout over time. Gray cast iron is the material of choice here for good reason. It has the heat capacity to soak up braking energy and the damping character that keeps noise and vibration down. It machines cleanly too, so the surface finish that meets your pads is consistent right out of the box.

The zinc coating covers the areas that don't see pad contact, the hat, the edges, and the vane openings. Those are the spots that turn orange with rust the first week a bare rotor sits on a car, and while surface rust on a hat is mostly cosmetic, a coated rotor looks right and stays cleaner behind an open wheel. The friction faces wear the coating off in the first few stops, which is normal and expected.

Fitment comes down to the numbers. The 6 x 120 millimeter bolt pattern, the 300 millimeter diameter, and the 19.90 millimeter thickness all have to match what your vehicle came with. The cleanest way to confirm this rotor is right for your application is to match the Hella part number, 355111282, against your vehicle's brake specifications before you order. If the numbers line up, it's a direct-fit replacement.

A few notes from years of doing brake jobs. Replace rotors in pairs across an axle so both sides wear and bite evenly, even if only one looks worn. This rotor is sold individually, so order two for a complete axle. The 19.90 millimeter figure is the nominal new thickness, and the minimum discard thickness is cast into the rotor itself, so you always have the wear limit in front of you. Fresh pads are a smart move any time you fit new rotors, and bedding them in with a series of moderate stops before you push hard gives you a clean, quiet transfer layer and full braking feel from day one.

How do you know it's time for new rotors? Pulsing through the pedal or a shimmy in the wheel under braking usually means a rotor is warped or worn unevenly. Deep scoring you can catch a fingernail on, a lip built up at the outer edge, or thickness that's dropped to the discard limit all say the same thing. Replace it. A worn rotor never gets better, and it drags down the performance of even a fresh set of pads.

Hella has been building lighting and braking components for the aftermarket and original-equipment market for a long time, and the reputation is earned on parts that go in and just work. There's no exotic material story here and no gimmick. It's a properly cast, correctly dimensioned, corrosion-protected rotor at a fair price. For a lot of owners doing their own brake work in the driveway, that's the whole ask. A part that meets spec, fits the first time, and lasts.