Hella 355109432 Vented Disc Brake Rotor, 330mm, 6x112, Sold Single

This is a genuine Hella disc brake rotor, part number 355109432. It's a vented, one-piece rotor cast from zinc-coated gray cast iron, and it measures 330mm across the outside diameter with a 32mm nominal thickness. The bolt circle is 6 x 112 mm, the center bore is 67mm, and the overall height comes in at 64.40mm. It ships as a single rotor, so you can order one side or grab a matched pair for the axle.

The vented construction is the part that matters most when the brakes are working hard. Instead of one solid slab of iron, a vented rotor is two friction faces with vanes cast between them. As the wheel turns, those vanes act like a fan and pull cooling air through the middle of the rotor. That heat management is what keeps your pedal firm on a long grade or after a string of hard stops, and it's why vented rotors show up on the busier axle of most vehicles.

Hella cast this one as a single piece rather than a two-part assembly. A one-piece rotor keeps runout predictable and makes the install a straight bolt-on with no extra hardware to fuss over. The zinc coating is there to fight corrosion. Bare cast iron starts to bloom orange surface rust the first time it sees rain, and while the pad wipes the friction face clean every stop, the hat, the outer edge, and the cooling vanes never get touched. The zinc keeps those areas looking clean and slows the rust that can otherwise flake into the vanes over a wet season.

Fitment comes down to the numbers. That 6 x 112 mm bolt pattern and 67mm center bore are common across a wide range of European cars, vans, and SUVs, and the 330mm vented size is the kind you'll usually find on the front axle. But bolt pattern alone doesn't guarantee a fit. Rotor diameter, thickness, and hat height all have to match your caliper and hub, so the safe move is to confirm part number 355109432 against your vehicle by VIN or a parts catalog before you order. If the number matches, you're good.

One more fitment detail worth calling out: the 67mm center bore is hub-centric, meaning the rotor and wheel locate off the hub itself rather than off the studs. That matters for smoothness. A hub-centric fit keeps the rotor dead-centered so you don't chase a phantom vibration that's really just a rotor sitting slightly off axis. Match the 67mm bore and the 6 x 112 mm pattern and everything indexes the way the factory intended.

A couple of install notes from years of doing brake jobs. Replace rotors in pairs on the same axle, even if only one side looks worn. Braking is a balance act left to right, and a fresh rotor paired with a tired one pulls the car under hard stops. Fresh rotors also deserve fresh pads. New pads seat into the exact surface of a new rotor, and reusing glazed old pads on a new rotor is the fastest way to end up with noise and vibration. Once everything's bolted up, bed the brakes in with a series of moderate stops from moderate speed to lay down an even transfer layer before you lean on them hard.

Know when a rotor is actually done, too. If you're feeling a pulse through the pedal, seeing deep scoring, or measuring below the minimum thickness stamped on the hat, it's time. Machining a thin rotor to chase a vibration usually just buys you a few months before it warps again, so on a rotor this size most techs just replace it. Hella has been building vehicle parts for decades, and that fit-and-forget approach carries over here. It's a straightforward replacement rotor that goes on clean and does its job.