do not press the back button…
-
Engine Parts
-
- Engine Cooling Coolant Hoses and Pipes (Front engine cars) Coolant Hoses and Pipes (Rear engine cars) Water / Coolant Radiators Track & Race Coolant Radiators Water / Coolant Pumps Coolant Bottles / Expansion Tanks Thermostat / Temperature Sensor Oil Radiators / Heat Exchangers Engine Oil Coolant / Antifreeze
-
- Engine Rebuild Parts Oil System Parts Fuel System Parts Gaskets & Sets Radial Seal / RMS / Camshaft / Balance shaft Belts / Tensioners / Rollers Chains & Tensioners Engine Bearings / Shells Engine Valves / Guides / Springs Engine Bolts / Studs Engine Mounts Engine Cylinders / Liners / Pistons Connecting Rod Cylinder Head / Camshaft Carrier Camshaft covers / Gaskets Camshaft gears / sprockets and fixings Crankcase Parts Crankshaft & Parts Turbo Chargers / Intercoolers & Parts Air Intake & Injection Vacuum Pump Specialist Tools
-
-
Brakes
-
- Brakes Brake Pads & Disc Package SPORTS Brake Pads & Disc Package Brake Disc Standard Brake Pads Standard SPORTS Brake Disc Brembo Standard brakes Brembo Racing brakes TEXTAR Brakes PAGID Racing Brakes Zimmermann Brakes Performance Friction Brakes Giro Slotted Brake Disc SHW Performance Brakes EBC Brakes Rotinger Graphite Line Replacement for Ceramic Disc Brake Pad Wear Sensors Brake Pad Anti-vibration shims Caliper Bolts / Disc Screws Pin Kit and Guide Plates Performance Brake Hoses Standard Brake Hoses All Categories
-
-
Suspension & Steering
-
- Steering Parts Steering Racks Steering Gaiter Track Rods
-
-
Transmission
-
- Gearbox / Transmission Clutch Kits Clutch Kits - High Performance Clutch Release Bearings Clutch Bolts Gearbox Parts Driveshafts & Parts Gasket Sets / Gaskets / Seals / Lock Nuts Gearbox Mounts Gearshift Control Parts Flywheel / Torque CV Joints Kits CV Boots and Kits Cardan Shaft / Prop Shaft Gearbox / Differential Oil Gearbox Sump / Oil Pan Rear Differential Transmission Cooling
-
- Cooling & Heating
-
Electrical & Lighting
-
- Electrical & Relays Hazard Warning Switch Handbrake Switch Reverse Light Switch Window Switch Window Mechanism Electric Horn SmartTop Control Units Ignition Switch Indicator / Wiper Stalk Switch Roof / Sun Roof Switch Relays / Fuses Washer pumps / bottles / jets Alarms / Security / Central Locking Electronic Control Units Dashboard / Console Parts & Switches Door Mirror Switch Phone Kits / Bluetooth / Ipod Air Bags & Parts Tracker Cruise Control Connector housing Wiring harness
-
-
Body & Exhaust
-
- Chassis / Bodywork Restoration Chassis / Repair Panels Front Lid Damper Rear Lid Damper Bonnets / Locks & Latches Boots / Rear Lid / Locks and Latches Bumpers Front Bumpers Rear Door Handles | Locks | Keys Door Panels | Hinges | Striker Plates Window Lifters | Motors Wings Front & Parts Wings Rear & Parts Side Sill Panels Exterior Chassis Mouldings Mirrors & Parts Stone Chip Foils / Stickers Undertrays Chassis & Engine Front Wiper Arms & Blades Wheel Arch Liners & Covers Roof - Cabrio / Targa / Coupe / Speedster Roll Cages Plastic Covers All Categories
-
-
Lubricants & Fluids
-
- Service Parts Service Kits Oil Filters Air Filters Pollen/Particle Filters Belts All Types Spark Plugs Ignition Coils Front Wiper Arms & Blades Rear Wiper Arms & Blades Gearbox Service Parts Engine Oil & Lubricants - Mobil Engine Oil & Lubricants - Total Engine Oil & Lubricants - Castrol Engine Oil & Lubricants - Motul Engine Oil & Lubricants - Millers Oils NanoDrive Engine Oil & Lubricants - Millers Oils Fuel Additives Coolant / Antifreeze Garage PPE
-
-
All Parts
-
- Parts Accessories Chassis / Bodywork Brakes Clothing & Gifts Electrical & Relays Engine Cooling Engine Electrical Engine Rebuild Parts Engine Tuning Exhausts Exterior Styling / Spoilers Gearbox / Transmission Heating / Air Conditioning Hydraulics Interior & Accessories Incar / Multimedia Lighting Mats & Carpets Motorsport and Off-Road Parts for Other Cars Pedal Cluster Rubber Seals All Categories
-
- Back to main website
Enter your VAT number here and click Verify:
Your details have been verified. VAT number registered to:
,
.
Your order will now be zero rated for VAT purposes. We reserve the right to verify these details after your order request has been made and reinstate VAT if required.
Your VAT details were not recognised or were invalid. Your VAT number must be matched to your Billing Country as specified above. This is currently specified as . You do not need to enter the country code part of your VAT number as this has already been selected in your billing address details above.
The VAT number checking service is currently offline. Please supply your VAT details within the comments or special instructions field below and we will apply a VAT discount after placing your order request.
Brake caliper seal kit, Rear. Porsche 911 Turbo 78-89 ❭ PO-930RBCKIT
- Porsche 911 1978-1989 3.3L Turbo (930)
Rebuilds one rear caliper
Includes:
4x 93035255400 Brake caliper piston scraper rings (Boot)
4x 93035255302 Brake caliper piston sealing rings

Porsche 911 (930) Turbo 1978-89
Diagram ref no 42 and 43.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
PO-930RBCKIT
The product you are viewing cross references to these numbers
Price is each seal
**Please check the piston size you need as some callipers take two different sizes.
Fits:
Various Models
Price is each seal
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
1055955
The product you are viewing cross references to these numbers
Brake Caliper Replacement Pistons for Brembo Calipers
Sold each
Restore the performance and reliability of your Porsche Brembo braking system with these OE Match Brake Caliper Replacement Pistons. Manufactured to original equipment specifications, these precision-engineered pistons are designed for rebuilding Brembo brake calipers fitted to a wide range of Porsche models.
Available in 28mm, 30mm, 32mm, 34mm, 36mm, 38mm, 40mm and 44mm outer diameters, every piston has an overall height of 32mm and is manufactured to deliver the correct fit, smooth operation and dependable sealing performance when used with new piston seals and dust boots.
Important: Please check the piston diameter required for your specific caliper before ordering. Many Brembo calipers use two different piston diameters within the same caliper to optimise braking performance. The sizes listed refer to the outer diameter (OD) of the piston.
What Does a Brake Caliper Piston Do?
The brake caliper piston is one of the most important components inside the braking system. Hydraulic brake fluid pressure pushes the piston forward, forcing the brake pad firmly against the brake disc to generate the friction required to slow or stop the vehicle.
Its primary functions include:
- Converting hydraulic pressure into braking force.
- Applying even pressure across the brake pads.
- Ensuring smooth and consistent piston movement.
- Maintaining balanced braking performance.
- Supporting Porsche ABS and stability control systems.
- Delivering precise pedal feel and braking response.
Correctly functioning pistons are essential for maintaining the powerful, progressive braking performance expected from Porsche Brembo calipers.
Why Do Brake Caliper Pistons Fail?
Brake caliper pistons operate in harsh conditions and are continually exposed to heat, moisture and brake dust. Over time they can become damaged or worn.
Common causes include:
- Corrosion caused by moisture ingress.
- Torn or damaged dust boots.
- Contaminated brake fluid.
- Surface pitting.
- Heat generated during heavy braking.
- Seized pistons caused by corrosion.
- Damage during previous repairs.
- High mileage and normal wear.
A damaged piston can prevent the caliper from operating correctly, leading to reduced braking performance and uneven brake pad wear.
Symptoms of a Worn or Damaged Caliper Piston
Common symptoms include:
- Sticking or seized brake calipers.
- Uneven brake pad wear.
- Vehicle pulling during braking.
- Reduced braking performance.
- Overheating brakes. Brake drag.
- Fluid leaks around the piston seal.
- Difficulty retracting the piston during servicing.
Replacing damaged pistons during a caliper overhaul restores smooth operation and reliable braking performance.
When Should Brake Caliper Pistons Be Replaced?
Replacement is recommended whenever:
- Corrosion or pitting is visible.
- Pistons become seized or difficult to move.
- The caliper is being rebuilt.
- Dust boots have failed allowing contamination.
- Brake fluid leaks occur around the piston.
- Uneven pad wear is caused by sticking pistons.
- Restoring older Brembo brake calipers.
- During preventative maintenance on ageing braking systems.
For the best results, new pistons should always be installed with new piston seals and dust protection boots.
OE Match Quality You Can Trust
These OE Match Brake Caliper Replacement Pistons offer:
- Manufactured to original equipment specifications.
- Precision-machined finish.
- Excellent corrosion resistance.
- Smooth piston movement.
- Direct replacement fitment.
- Suitable for Brembo brake calipers.
- Available in 28mm, 30mm, 32mm, 34mm, 36mm, 38mm, 40mm and 44mm diameters.
- Uniform piston height of 32mm.
- Ideal for professional caliper rebuilding.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
1055955
The product you are viewing cross references to these numbers
- Porsche Boxster 718 2.0L Manual (300 Bhp) 2017>>
- Porsche Boxster 718 2.0L PDK (300 Bhp) 2017>>
- Porsche Boxster S 718 2.5L Manual (350 Bhp) 05/2017>>
- Porsche Boxster S 718 2.5L PDK (350 Bhp) 05/2017>>
- Porsche 991.1 Carrera C2S / GTS 3.8L (400/430 Bhp) 2012-16
- Porsche 991.1 Carrera C4S / GTS 3.8L (400/430 Bhp) 2012-16
- Porsche 991.1 Turbo 3.8L (520 Bhp) 2014-16
- Porsche 991.1 Turbo S 3.8L (560 Bhp) 2014-16
- Porsche 991.1 R 4.0L (500 Bhp) 2016
- Porsche 991.1 GT3 3.8L (475 Bhp) 2014-16
- Porsche 991.1 GT3 RS 4.0L (500 Bhp) 2015-16
- Porsche 991.2 Carrera 2S / GTS 3.0L (420/450 Bhp) 2016-19
- Porsche 991.2 Carrera 4S / GTS 3.0L (420/450 Bhp) 2016-19
- Porsche 991.2 Cabriolet 2S / GTS 3.0L (420/450 Bhp) 2016-19
- Porsche 991.2 Cabriolet 4S / GTS 3.0L (420/450 Bhp) 2016-19
- Porsche 991.2 Targa 4S / GTS 3.0L (420/450 Bhp) 2016-19
- Porsche 991.2 Turbo Coupe 3.8L (540 Bhp) 2016-19
- Porsche 991.2 Turbo S Coupe 3.8L (580 Bhp) 2016-19
- Porsche 991.2 Turbo Cabriolet 3.8L (540 Bhp) 2016-19
- Porsche 991.2 Turbo S Cabriolet 3.8L (580 Bhp) 2016-19
- Porsche 991.2 GT3 4.0L (500 Bhp) / GT3 RS 4.0L (520 Bhp) 2017-19
- Porsche Cayman GT4 3.8L 2015-16
- Porsche Cayman 718 2.0L Manual (300 Bhp)
- Porsche Cayman 718 2.0L PDK (300 Bhp)
- Porsche Cayman S 718 2.5L Manual (350 Bhp)
- Porsche Cayman S 718 2.5L PDK (350 Bhp)


Porsche 991.1 Carrera 2S / 4S 2012-16
Porsche 991.2 Carrera 2S / 4S 2017>>
Porsche 991 Turbo / GT2 / GT3 2012>>
Porsche 718 (982) Boxster 2017>> I450 Cars with Ceramic brakes (PCCB)
Porsche 718 (982) Cayman 2017>> I450 Cars with Ceramic brakes (PCCB)
Porsche 981 Cayman GT4 2016
Click 'Zoom in' for large parts diagram.
Diagram ref no 15
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
97035195901
The product you are viewing cross references to these numbers
Monday-Friday: 8.30am - 5.30pm (GMT)
Saturday: Closed
Sunday: Closed