Replacement Rotors: PRK.088.345.240.19500.08.03.R

Paragon 2-piece Rotors (Rear Pair) for BMW Z4 (G29) / M Sport / M Performance (Gxx)

Rev up your BMW Z4 (G29) or M Sport / M Performance (Gxx) with these Performance OE Replacement Rotors! Measuring 345mm x 24mm (13.58" x 0.94"), these rotors provide superior performance and precision, giving you the edge you need to conquer any road. Upgrade your ride today and experience the thrilling benefits of these BMW rotors!

Made of CM-250 special formulated high carbon alloy cast iron, it allows for an optimal bite, thermal characteristics, high-temperature strength and durability. Rotor rings are heat treated to release stress in the rotor to avoid deformation and vibration then turned by state-of-the-art CBN surface machining to ensure better break-in with new brake pads.

Vibration is reduced as the rotor lateral run-out is kept within 0.03mm and well-balanced: variations are kept within 2 grams. All rotors went through rigorous quality control procedures and inspections to ensure the rotors are fit for their purposes. The floating 2-piece design allows thermal expansion of the rotor while minimizing deformation and ensuring the rotor is self-centered with the pads. A slotted rotor improves braking consistency by maintaining a clean contact surface and dissipate heat generated and gases released when the pads come into contact with the rotors. Slotted rotors have a superior advantage over blank rotors in wet or raining conditions by preventing water films to form between the brake pad and rotor surface. Weighing less than most O.E. rotors while maintaining proper thermal capacity, our 2-piece rotors improves overall handling by saving unsprung mass.

Aluminum hats are CNC machined from lightweight 6061-T6 aerospace grade aluminum for high strength and durability under extreme track conditions, then black hard coat/hard anodized to increase resistance to wear and corrosion. Mil-spec Type III anodized hats will not discolor under extreme heat, and are harder and more wear/scratch resistant. Unnecessary materials are taken out from the aluminum hats for maximum weight savings while maintaining proper structural integrity.
*Black hard coat and hard coat anodized hats are the same in terms of performance and durability.

• Direct bolt-on without any modifications and designed to work flawlessly with OEM Brembo calipers, ABS, and brake system while maintaining factory brake bias. Compatible with OEM brake pads or aftermarket pads with the same pad depth (D)

• Directional ventilation vanes for optimal cooling performance, runs up to 30% cooler than O.E. rotors and increase cooling efficiency by up to 30%

• Floating 2-piece design

• Minimizing brake fade & judder during extended sessions

• Rotor to hat mounting system: D-Bobbin (short) - 10 bolt

• Slotted friction face

• Weighs 16.7 lbs (7.55 kg) - save 1.7 lbs of unsprung weight per rotor vs. OEM

Direct replacement of: OEM BMW part number 34216860925

***Fits various BMW Gxx applications with standard/M Sport/M Performance 345x24 rear brakes:

3 Series

2019+ G20 330i (M Sport)
2019+ G20 M340i
2019+ G20 M340i xDrive

4 Series

2021+ G22/G23 430i / 430i (M Sport)
2021+ G22/G23 430i xDrive
2021+ G22/G23 M440i
2021+ G22/G23 M440i xDrive

5 Series

2017+ G30 530i / 530i (M Sport)
2017+ G30 530i xDrive
2017+ G30 540i / 540i (M Sport)
2017+ G30 540i xDrive
2017+ G30 M550i xDrive

X3

2019+ G01 X3 M40i

X4

2019+ G02 X4 M40i

Z4

2020+ G29 Z4 30i (M Sporto<

2020+ G29 Z4 M40i

Includes:

• One pair of Paragon Performance 345mm x 24mm (13.58” x 0.94”) 2-piece rotor assemblies with black hard coat/hard anodized 6061-T6 aerospace grade aluminum hats, stainless steel bobbins, and anti-rattle clips (assembled and ready to install)

• Detailed installation manual

Part # (w/ black hard anodized hat): P2R.088.345.240.19500.08.03.01.R

Part # (w/ hard anodized hat): P2R.088.345.240.19500.08.03.02.R

Extra/replacement hardware is available for purchase. We recommend using new hardware when replacing rotors to ensure the rotor ring is attached to the aluminum hat properly. Please refer to our Rotor Assembly Instructions for torque specs and detailed instructions.

Best For: BMW Drivers Who Value Sharp Response and Repeatable Braking

These rotors are well matched to BMW applications where steering precision and brake feel are part of the driving experience. They suit daily-driven performance cars, mountain-road use, and occasional HPDE events where repeatable response matters more than flashy claims.

FAQ

Are these complete rotors or replacement rings?
This listing is for a complete 2-piece rotor assembly where specified, with the hats included and the parts assembled ready to install.

Do these reuse factory hats?
No. On listings sold as complete Paragon 2-piece rotor assemblies, the rotor hats are included. If your vehicle originally uses a factory 2-piece rotor, some other service-part listings may reuse the OE hats, but this product is sold as a complete assembly.

Do slotted rotors improve braking?
Slots primarily improve pad cleaning and help maintain consistent braking feel under heat. They do not create a dramatic change in stopping distance by themselves, but they can help the system stay more consistent during repeated hard stops.

When should rotor rings be replaced?
A practical wear indicator is slot depth. When the slots become shallow and much less visible, the rotor is typically nearing the end of its effective service life. Rotor thickness, heat checking, cracking, and brake vibration should also be inspected during service.

Should I replace pads at the same time?
Yes, in most cases. Fresh pads help the new rotor surface bed in correctly and reduce the chance of uneven deposits, noise, or inconsistent pedal feel.

Brake Rotor Technology

Why high-carbon rotors matter
High-carbon cast iron offers better thermal stability than generic low-cost rotor materials. That helps the rotor maintain more consistent behavior as temperature rises, which is important on heavier vehicles and on cars driven aggressively.

Directional vane cooling
Directional internal vanes are designed to move air through the rotor more effectively, improving heat evacuation and helping the rotor recover more quickly between braking events.

Slotted rotor surface
Slots help keep the pad face clean by clearing away gases, dust, and debris. The result is more consistent pad contact and more repeatable braking feel, especially when the system is worked hard.

When to Replace Rotor Rings

Rotor rings should be replaced when the friction surface shows meaningful wear, heat fatigue, or thickness loss. One of the easiest visual indicators is the depth of the rotor slots. As the rotor wears, the slots become shallower. When they are much less visible, the rotor is generally nearing the end of its useful service life.

Other common signs include visible heat checking or cracking, brake pulsation, heavy scoring, and rotor thickness approaching the service limit.

Why Replace Rotor Rings Instead of the Whole Rotor?

This application uses a 2-piece design because separating the friction ring from the hat improves serviceability, heat management, and weight control. Compared with a heavy one-piece replacement, a quality 2-piece assembly can better suit performance-oriented vehicles where repeated heat cycles matter.

Common Mistakes When Replacing Rotors

• Reusing worn pads on a fresh rotor surface
• Skipping the pad and rotor bedding process
• Not cleaning or inspecting the hat, hardware, and mounting faces
• Ignoring brake fluid condition during brake service
• Ordering the wrong configuration for the vehicle or hat type

Taking care of these details helps the new rotor deliver the braking feel, wear life, and consistency it was designed to provide.

Recommended Companion Parts

Rotor service is also a good time to inspect or replace the brake pads, rotor hardware where applicable, and brake fluid. On performance applications, fresh pads and fluid often have as much impact on brake feel as the rotor itself.

Need help confirming fitment or choosing the right supporting parts?
Our team specializes in performance brake systems and can help you choose the right combination for your vehicle and how you use it.