Description
Maximize heavy-duty fleet safety and achieve reliable, fade-free stopping power with the genuine Knorr-Bremse 22.5″ Air Disc Brake Caliper Assembly. Designed specifically for 22.5-inch wheel end platforms (including industry-leading SN7, SB7, and SK7 variants), this robust caliper assembly delivers immense clamping force for long-haul trucks, heavy coaches, and multi-axle freight trailers. Worn slide sleeves, seized internal tappets, and corroded housings severely compromise braking efficiency over time, resulting in extended stopping distances and costly maintenance downtime. This premium replacement caliper assembly solves those challenges directly. It utilizes high-strength nodular cast iron, precision-machined internal guide mechanisms, and high-temperature seals to provide rapid pneumatic actuation, ensure uniform pad-to-rotor contact, and withstand severe highway and vocational abuse.
Technical Parameters
| Category | Specifications & Technical Details |
| 22.5-Inch Large-Diameter Twin-Piston Clamping System | We optimize this caliper specifically for 22.5-inch heavy-duty wheel ends. The large-diameter twin pistons convert incoming air pressure into exceptionally strong and even disc clamping force. As a result, large-tonnage vehicles achieve instant hard braking capability at highway speeds. |
| High-Thermal-Capacity Anti-Fade Housing Structure | We cast the caliper body from heavy-duty high-strength nodular cast iron. This delivers outstanding structural rigidity and thermal conductivity. Moreover, it effectively prevents high-temperature thermal fade and structural deformation caused by continuous long downhill braking. |
| Dual-Sealed Self-Cleaning Floating Guide Pin Mechanism | We equip the caliper with precision-machined axial sliding guide pins and double-lip high-temperature dust boots. Consequently, it maintains smooth axial movement under the high-frequency torsion and bouncing of multi-axle heavy trucks. Meanwhile, it completely blocks mud, de-icing salt, and road moisture intrusion. |
| Integrated Maintenance-Free Automatic Clearance Adjuster | We integrate a high-precision internal automatic wear compensation mechanism. It steplessly fine-tunes working clearance as brake pads naturally wear. Therefore, brake pedal travel stays highly consistent throughout the entire friction pad service life. |
| All-Weather Extreme Thermal & Salt-Spray Composite Defense | We develop this caliper for extreme environments from -40°C cold to +900°C high temperature. Additionally, the surface carries a multi-layer anti-corrosion and anti-oxidation coating. As a result, it perfectly resists de-icing salt and moisture erosion under harsh road conditions. |
Applicable Car Brands & Models
Common warning symptoms include:
Vehicle Pulling to One Side During Braking: The heavy truck or trailer pulls heavily left or right due to a seized, stuck, or sluggish caliper piston.
Brake Drag or Overheated Wheel Hubs: The brake pad fails to retract completely after pedal release, resulting in continuous friction, burning smell, and extremely hot wheel rims.
Significantly Reduced Braking Efficiency: A noticeable loss in overall stopping power, requiring much higher pedal effort and extended stopping distances.
Visible Air Leaks or Boot Damage: Hissing sounds around the pneumatic interface or torn guide pin boots packed with road debris and rust.
While official Knorr-Bremse service repair kits (such as guide pin kits, boot sets, and seal mechanisms) are available for minor routine maintenance, complete caliper assembly replacement is strongly recommended if the main cast iron housing is cracked, heavily corroded, or if internal guide bores are structurally scored.
Yes, absolutely. After installing a new caliper assembly, technicians must manually verify running clearance, test the pneumatic system for air leaks using soapy water, and conduct a road or brake-roller test to ensure proper braking balance across the axle.
Each caliper assembly is bolted securely to a custom-molded industrial wooden or heavy corrugated cardboard base, wrapped in anti-corrosion VCI barrier film, and fitted with heavy-duty port plugs to protect precision machined surfaces and threads during global transit.
