Remanufactured CAT C12 12.0L (732 ci) Engine For Sale
1997–2005 — 340–490 hp | 1,250–1,650 lb-ft
The Caterpillar C12 was introduced in 1997 as a versatile mid-range diesel engine that bridged the gap between the medium-duty C7 and the heavy-duty C15. With 12.0 liters of displacement, the C12 offe...
Starting from $6,000 – $11,000 — 1-Year Unlimited Mileage Warranty
CAT C12 Technical Specifications
About the Caterpillar C12 Engine
The Caterpillar C12 was introduced in 1997 as a versatile mid-range diesel engine that bridged the gap between the medium-duty C7 and the heavy-duty C15. With 12.0 liters of displacement, the C12 offered a compelling combination of power and efficiency that made it especially popular in vocational applications — fire trucks, dump trucks, concrete mixers, and refuse haulers. The C12 was also a popular choice for highway trucks where the full power of a C15 wasn't necessary. One of the C12's greatest advantages is its pre-ACERT design, which means no EGR, no DPF, and no complex emissions aftertreatment equipment. This simplicity makes the C12 highly reliable and easy to maintain. The engine was replaced by the C13 ACERT in 2005, but the C12 remains popular in the used market for its proven reliability and straightforward design.
CAT C12 Strengths
- Pre-ACERT design — no EGR, no DPF, no complex emissions equipment
- Excellent reliability with a simple, proven mechanical design
- Versatile power range suitable for highway, vocational, and specialty applications
- Popular in fire trucks and emergency vehicles for its dependability
- Good fuel economy for its displacement class
- Strong parts availability — shares many components with C10 and C15 families
Common CAT C12 Issues (Addressed in Our Remanufactured Engines)
- Injector sleeve leaks on high-mileage engines can cause coolant contamination
- Oil pump wear on engines with extended oil change intervals
- Turbocharger bearing failures on high-hour engines
- Cylinder liner pitting from coolant chemistry issues (SCA maintenance critical)
- Front and rear main seal leaks on high-mileage engines
- ECM connector corrosion on engines exposed to harsh environments
Vehicles with the CAT C12
Available CAT C12 Remanufactured Engines
CAT C12 Buying Guide
When purchasing a remanufactured Caterpillar C12, verify the horsepower rating matches your application — ratings range from 340 hp for vocational use to 490 hp for highway applications. The C12 uses the same MEUI fuel system as the 3406E, so parts are widely available. Check the engine serial number prefix: 2KS and MBL are common prefixes. A quality remanufactured C12 should include new injectors, rebuilt turbo, new injector sleeves, and a complete gasket set. The C12's pre-ACERT design makes it one of the most straightforward CAT engines to rebuild and maintain.
Frequently Asked Questions — CAT C12
How much does a remanufactured Caterpillar C12 engine cost?
A remanufactured Caterpillar C12 engine typically costs between $6,000 and $11,000 depending on the horsepower rating and application. The C12's pre-ACERT design makes it less expensive to remanufacture than later ACERT models. All our CAT C12 engines are fully dyno tested and backed by our comprehensive warranty. Call (631) 991-7700 for an exact quote.
Is the CAT C12 a good engine?
Yes, the Caterpillar C12 is an excellent engine known for its reliability and simplicity. Its pre-ACERT design means no EGR or DPF equipment, making it one of the most dependable CAT truck engines. The C12 is especially popular in fire trucks and vocational applications where reliability is critical. Many C12 engines have exceeded 500,000 miles with basic maintenance.
What are common Caterpillar C12 problems?
Common C12 issues include injector sleeve leaks (causing coolant in oil), oil pump wear, turbocharger bearing failures, and cylinder liner pitting from poor coolant maintenance. Front and rear main seal leaks are also common on high-mileage engines. Our remanufactured C12 engines address all known issues with new sleeves, seals, and updated components.
What trucks use the Caterpillar C12 engine?
The Caterpillar C12 was installed in Peterbilt 379/385/357, Kenworth T800/T600/W900, Freightliner FL112/Columbia, and International 9200i trucks. It was especially popular in vocational applications including fire trucks, dump trucks, concrete mixers, and refuse haulers where its reliability was critical.
What replaced the Caterpillar C12?
The Caterpillar C13 ACERT replaced the C12 in 2005. The C13 offered a slightly larger displacement (12.5L vs 12.0L), more power (up to 520 hp vs 490 hp), and ACERT emissions technology. While the C13 is more powerful, many buyers prefer the C12 for its simpler pre-ACERT design and proven reliability.
How many miles can a CAT C12 last?
A well-maintained Caterpillar C12 can last 500,000 to 750,000 miles before requiring a major overhaul. In fire truck and vocational applications with lower annual mileage, C12 engines routinely last 15–20+ years. The key to longevity is regular oil changes, proper coolant maintenance (SCA levels), and timely valve adjustments.
Caterpillar Troubleshooting Guides
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Step-by-step guide for installing your remanufactured engine.
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