Cummins Engine Rebuild Parts Looking for reliable and affordable Cummins rebuild kits? Whether you’re rebuilding a Cummins ISX15, N14, 6BT, or QSB, our complete engine overhaul kits give you everything you need to restore power, performance, and reliability — all in one box. At HeavyDutyKits.com, we stock high-quality inframe and out-of-frame Cummins rebuild kits tailored to your engine's exact CPL and ESN. Backed by expert support, nationwide shipping, and no upfront core charges — we make rebuilding your diesel engine easier and more cost-effective. What’s Included in Our Cummins Overhaul Kits? Every HDKits rebuild package is assembled to meet OEM specs and includes all major components for a successful engine rebuild. Depending on your needs, we offer: In-Frame Rebuild Kit: Includes pistons with rings, cylinder liners, piston pins with snap rings, rod and main bearings, thrust washers, and a complete in-frame gasket set. Optional: camshaft bushings, oil seals, and valvetrain components depending on engine model. Out-of-Frame Overhaul Kit: Includes everything in the in-frame kit plus additional parts for a full teardown: camshaft bushings, rear main seal, front crank seal, oil pump or water pump depending on package, and a full gasket and hardware set for reassembly. CPL-Matched Guarantee: Every kit is CPL-matched to your specific engine build, ensuring you receive the correct pistons, liners, and bearings for a perfect fit — whether it’s a classic 855 Big Cam or a modern ISX/QSX series. Supported Cummins Engine Models We offer rebuild kits for the most popular Cummins diesel engines, including: ISX / ISX15 / QSX — CM570, CM870, CM871, CM2250, CM2350 N14 / M11 — Red Top, Celect, Celect Plus 6BT / 5.9L / 12V / 24V — Automotive, Industrial, Marine QSB / QSK / B3.3 — Off-road, AG, Doosan, Hitachi, Bobcat 855 / NT / NH — Classic heavy-duty Cummins platforms Not sure which kit fits your engine? Just provide your Cummins CPL number or engine serial number ESN, and we’ll quickly match the right kit for you. Most Demanded Rebuild Kits Cummins ISX Rebuild Kits: https://www.heavydutykits.com/product-category/cummins-diesel-engines/isx-series/engine-rebuild-kits-for-isx-series/ Cummins N14 Overhaul Kits: https://www.heavydutykits.com/product-category/cummins-diesel-engines/n14-series/engine-rebuild-kits-for-n14-series/ Cummins 6BT Inframe Kits: https://www.heavydutykits.com/product-category/cummins-diesel-engines/b-series/cummins-6bt-5-9/ Contact Us – Fitment by CPL Lookup: https://www.heavydutykits.com/contacts/ FAQs What’s the difference between an inframe and out-of-frame rebuild kit? An inframe kit includes pistons, liners, bearings, and gaskets for repairs done with the engine in the truck. An out-of-frame kit adds components for a full engine teardown, including cam bushings, rear main seal, and more. How do I find the right Cummins rebuild kit? You’ll need your CPL number or engine serial number. This ensures the pistons, liners, and bearings match your exact engine build. Are these aftermarket or OEM kits? We offer both. Our aftermarket kits are from trusted names like PAI, Mahle, IPD, and McBee — engineered to meet or exceed OEM standards. Why Choose HeavyDutyKits? No Core Charges Upfront: No expensive deposit or exchange needed when you order. Free Nationwide Shipping: Fast, free delivery anywhere in the USA. Diesel Experts on Call: Our experienced team can assist with fitment, installation tips, and questions. 100% CPL Fitment Guarantee: We ensure your kit matches your engine’s CPL for an exact fit. Fast Delivery & Easy Ordering: Quick turnaround times and a smooth ordering process mean less downtime. Have a question or need help? Send us your engine CPL or ESN and we’ll guide you to the right kit — fast.