OEM Precision Rebuilt to Outperform Factory Standards

The Knorr-Bremse 5012533X Air Compressor was the factory-standard compressor installed on Caterpillar C13 and C15 engines between 2004–2007, widely used across Freightliner, Peterbilt, Kenworth, and International heavy-duty trucks.
This two-cylinder, water-cooled compressor was designed by Knorr-Bremse under Caterpillar specification to deliver high output, long service intervals, and superior heat dissipation in demanding long-haul and vocational applications.

At Turbo Kings, every 5012533X compressor undergoes a complete teardown, cleaning, and precision rebuild process — restoring each unit to full OEM function and reliability. We don’t “reseal” — we remanufacture. Each compressor is fully disassembled, media-cleaned, and ultrasonically flushed, ensuring that all oil, carbon, and coolant residue are removed from critical internal passages.

Once cleaned, all internal components — including pistons, rings, rods, bearings, and valves — are replaced with OEM-spec or better components. Cylinder heads and sealing decks are resurfaced to precise tolerances, guaranteeing proper compression and sealing integrity.
Each unit is bench-tested under pressure at full operating load, verifying compression ratio, airflow output, oil control, and cooling efficiency before it’s approved for sale.

This model is direct-fit compatible with 2004–2007 Caterpillar C13 and C15 engines and their OEM cross-references under Knorr-Bremse and Caterpillar interchange numbers (including 5012533, 5012533X, and select 010-100 series supersessions).

Turbo Kings Rebuild Highlights

• Ultrasonically Cleaned Air & Coolant Passages – Restores full flow and cooling efficiency while preventing carbon buildup.
• OEM-Grade Component Replacement – Every piston, ring, valve, and bearing replaced to Knorr-Bremse spec.
• Precision Machined Sealing Surfaces – Ensures leak-free performance and restored compression efficiency.
• Bench-Tested at Load Pressure – Each unit pressure-tested for flow rate, oil control, and leak integrity.
• Ready for Installation – Delivered pre-lubricated and sealed for quick install on Caterpillar engines.
• Warranty Backed – Includes a 12-month unlimited-mileage warranty and core exchange support.

Specifications

• Manufacturer: Knorr-Bremse (OEM for Caterpillar)

• Part Number: 5012533X

• Cooling Type: Water-cooled

• Cylinders: Two

• Displacement: ~16.5 CFM @ 1250 RPM

• Drive Type: Gear-driven

• Applications: CAT C13 / C15 engines (2004–2007)

Applications

Compatible with:

• Caterpillar C13 / C15 (EPA04) – 2004–2007

• Freightliner, Peterbilt, Kenworth, International trucks equipped with CAT engines of this range