Hella Pagid 355115582 Rear Brake Rotor - Jaguar XJ 4.2L

The Hella Pagid 355115582 is a rear disc brake rotor built for the Jaguar XJ with the 4.2 liter V8, including the XJ8, XJ8 L, and Vanden Plas trims. It's a vented, one-piece casting in gray iron with a zinc coating that keeps the hat and edges from blooming with surface rust while the car sits. If your rear pedal feel has gone soft, or you're chasing a light pulse through the pedal at highway speed, a fresh pair of these back rotors is usually where you start.

Here are the numbers that matter at install time. The rotor measures 326 millimeters across the outside diameter with a 20 millimeter nominal thickness, and it stands 38.20 millimeters tall from the mounting face. The center hub bore is 64.5 millimeters and the wheel bolt pattern is 5 by 108 millimeters, which is the standard rear fitment on this generation of XJ sedan. Get those two dimensions right and everything else on the caliper lines up. Vented means there are cooling vanes cast between the two friction faces, so heat pulls out of the disc faster on long downhill runs and repeated stops.

The aluminum-bodied XJ is a big sedan that carries real speed, and the rear brakes do more work than people expect on a car this size. The rear axle handles a meaningful share of the stopping force, and it also carries the parking brake, so a clean, true rear rotor matters for both everyday driving and holding the car on a hill. Worn rear discs on these show up as a light shudder through the seat under braking, a soft or long pedal, or a rough lip you can feel when you run a finger across the edge of the disc.

The casting is gray cast iron, the same family of material the factory rotor uses, so pad bed-in and wear behavior stay predictable. The zinc coating is the practical upgrade. Bare iron rotors flash-rust within a day of rain, and that orange film creeps across the hat and outer edge where the pads never sweep. The zinc layer holds that off, so the wheel looks clean through the spokes and the parked disc doesn't turn crusty. Over the swept braking surface the coating wears away on the first few stops, which is normal and expected.

This is a rear-axle rotor, and brakes are always a two-side job. Replace both rear rotors together even if only one is scored, because mixing a new disc with a worn one gives you uneven pad contact and a car that pulls under braking. Plan on fresh rear pads at the same time. New pads on an old glazed rotor never seat right, and old pads on a new rotor drag their uneven wear pattern straight onto the new surface. Torque the caliper bracket and guide bolts to the Jaguar service spec, and bed the brakes in with a series of moderate stops from about 40 miles per hour before you lean on them hard.

A quick honesty note. This is sold as a single rotor, one disc per box, so order two for a complete rear axle. It's a direct-fit replacement disc, not a big-brake or slotted performance kit, and it doesn't come with pads or hardware. If your XJ has an earlier or later brake package, confirm your rear rotor is the 326 millimeter size before ordering, since more than one rear disc was used across the run. When in doubt, measure the old rotor's outside diameter and thickness and match it to the numbers above. We ship these the same day when they're in stock and ordered before 3 PM Eastern, so a weekend brake job doesn't have to wait. And if you're not sure this is the right disc for your car, send us the year and trim and we'll help you sort it out before you buy.