Cummins ISX, QSX Inframe Engine Rebuild Kit, Remanufactured (4376427)

Why Choose This Cummins ISX, QSX Inframe Rebuild Kit From 4BTdiesel?

• Every component in the kit is new, not used or reconditioned, built to OEM specifications and tolerances
• Manufactured in an ISO 9001 certified facility for quality and consistency throughout the entire kit
• No core charge required on any component in this kit
• Available in standard and undersized bearing options to match your specific engine condition
• Cross references 4352362, 4376427, 5473066, ISX111-049, ISX111-113, M-3050344, and M-4376427, among others
• Fits Cummins ISX Single Cam, ISX Dual Cam, QSX Single Cam, and QSX Dual Cam engine families

The Problem With OEM Rebuild Kits That Most Shops Do Not Know About

When an ISX or QSX reaches the point where an inframe overhaul is unavoidable, the first instinct for many shops and owner-operators is to go straight to the OEM kit. It seems like the safest call. What most people do not realize is that some OEM inframe rebuild kits include used or reconditioned parts, not new ones. That means your freshly torn-down engine could be going back together with components that have already accumulated heat cycles, wear, and fatigue. That is not a rebuild. That is just buying time.

What Is Included in This Cummins ISX, QSX Inframe Rebuild Kit

This inframe kit covers all of the primary wear components needed for a complete ISX or QSX overhaul without pulling the engine from the vehicle. The contents include six Cylinder Liner Kits (4376391), six Piston Kits (2881758), one Upper Engine Gasket Set (4376104), six Connecting Rod Bearings (4089405), one Main Engine Bearing Kit (5406110), one O-Ring Seal (3678756), one Pressure Relief Valve (4357177), one Oil Pan Gasket (4026684), and two product boxes for organized storage and transport during the rebuild process.

Rod bearing size and main bearing size are both required selections at checkout, with options including standard, .010, .020, .025, .030, and .50 to accommodate engines at different stages of wear or that have been previously machined. Selecting the correct bearing sizes is critical to a successful rebuild, and 4BTdiesel’s professionally certified factory mechanics can help you determine the right specification for your engine before the order ships.

This kit is a substantial package, weighing 216 lbs and shipping in a 46 by 16 by 17 inch container. Because diesel engine parts are engine specific, entering your Engine Serial Number or VIN on the product page before ordering allows 4BTdiesel’s team to confirm that this kit is the correct fit for your ISX or QSX application, whether single cam or dual cam.

Get Your Cummins ISX, QSX Inframe Rebuild Kit From 4BTdiesel

Order your Cummins ISX, QSX Inframe Engine Rebuild Kit (4376427) from 4BTdiesel today.

Frequently Asked Questions, Cummins ISX QSX Inframe Engine Rebuild Kit (4376427)

1. What engines does inframe rebuild kit 4376427 fit?

This kit is built for Cummins ISX and QSX diesel engines, covering ISX Single Cam, ISX Dual Cam, QSX Single Cam, and QSX Dual Cam engine families. 4BTdiesel recommends submitting your Engine Serial Number or VIN before ordering so our team can confirm this is the correct kit for your specific engine build.

2. What is included in the 4376427 inframe rebuild kit?

The kit includes six Cylinder Liner Kits (4376391), six Piston Kits (2881758), one Upper Engine Gasket Set (4376104), six Connecting Rod Bearings (4089405), one Main Engine Bearing Kit (5406110), one O-Ring Seal (3678756), one Pressure Relief Valve (4357177), one Oil Pan Gasket (4026684), and two product boxes for organized storage during the rebuild.

3. What is the difference between an inframe rebuild and a full overhaul?

An inframe rebuild allows the technician to replace the major internal wear components, including liners, pistons, rings, and bearings, without removing the engine from the chassis. The block stays in the frame, which reduces labor time and overall cost compared to a full out-of-frame overhaul. This kit is specifically designed and packaged for the inframe procedure on ISX and QSX engines.

4. Are all the parts in this rebuild kit new?

Yes. Every component in this kit is new, built to OEM specifications and tolerances, and manufactured in an ISO 9001 certified facility. 4BTdiesel does not include used or reconditioned parts in its rebuild kits, unlike some OEM kits that may contain previously used components.

5. What bearing sizes are available for this kit?

Both rod bearing size and main bearing size are required selections at checkout. Available sizes are standard, .010, .020, .025, .030, and .50 to accommodate engines at various stages of wear or previous machining. If you are unsure which size your engine requires, 4BTdiesel’s professionally certified factory mechanics can help you determine the correct specification before your order is placed.

6. Is there a core charge on this rebuild kit?

No. This ISX, QSX Inframe Rebuild Kit carries zero core charge. There is nothing to return and no additional deposit required at checkout, regardless of which bearing sizes you select.

8. What are the signs that my ISX or QSX needs an inframe rebuild?

Common indicators include excessive oil consumption or blowby at the crankcase breather, low or inconsistent compression across cylinders, engine knock from worn bearings, a significant drop in power or fuel economy, coolant contamination from a failed liner seal, and metal particles or shavings in the oil. Any combination of these symptoms suggests the internal wear components are due for replacement.

9. What OEM part numbers does this kit cross reference?

This kit cross references 4352362, 4376427, 5473066, ISX111-049, ISX111-113, ISX111049, ISX111113, M-3050344, M-4376427, M3050344, M4376427, PAIISX111-049, and PAIISX111049. If your current kit or any of its components carry any of these numbers, this 4BTdiesel kit is a correct replacement.

10. Can I finance this rebuild kit purchase?

Yes. 4BTdiesel offers financing through PayPal Pay Later and Sezzle at checkout. PayPal Pay Monthly provides 3, 6, 12, or 24 month payment options with $0 down for qualified buyers, making the $3,976.48 investment in your ISX or QSX overhaul much more manageable without delaying the repair any further.

What Rebuild Kit and Gasket Set Includes