KO SPEED KO58963S Box Performance Diesel Engine Assembled 4D56T/4D56 Cylinder Head

( Brand: Ko Speed ), ( Manufacturer Part Number: KO58963S ), ( Part Type: Box Engine Cylinder Head ), ( California Prop 65 Warning: This Product Contains Chemicals Known To The State. ), ( Style: Oe / Assembled Head ), ( Materials: Cast Aluminum / Steel ), ( Finish: Assembled ), ( Notes: Open Box Item; Ships In Original Factory Packaging )

Review KO SPEED Open box Performance 4d56t/4d56 Diesel Engine Assembled Cylinder Head Mitsubishi

The **KO KO58963S Open-Box Performance 4D56T/4D56 Diesel Engine Assembled Cylinder Head for Mitsubishi** represents a meticulously crafted, high-performance upgrade designed to elevate the power, efficiency, and reliability of your diesel-powered Mitsubishi vehicle. Engineered for compatibility with the legendary **4D56** and its turbocharged variant, the **4D56T**, this cylinder head assembly is a precision-engineered component built to withstand the demands of aggressive driving, heavy loads, and extended high-performance use. Crafted from high-grade materials, including durable cast iron or aluminum (depending on the specific variant), this head is designed to optimize airflow, combustion efficiency, and thermal management, ensuring consistent performance under stress. The **open-box condition** indicates that while the product has been handled and inspected, it remains in excellent, functional condition, free from major defects, and ready for immediate installation. Whether you're restoring a classic Mitsubishi truck, enhancing the power output of a daily driver, or preparing a vehicle for off-road or towing applications, this cylinder head delivers a robust foundation for improved engine performance. With proper installation and maintenance, it promises not only increased horsepower and torque but also enhanced durability, making it an essential component for enthusiasts and professionals alike who demand the best from their diesel engines.

### **Pros and Cons of Buying a Used/Open-Box Mitsubishi 4D56T/4D56 Diesel Engine Assembled Cylinder Head (KO KO58963S)**

1. **Cost-Effective Alternative to New Engines**

The open-box or used condition significantly reduces the price compared to a brand-new engine. This makes it an attractive option for budget-conscious buyers, especially those restoring or repairing older Mitsubishi vehicles (such as the L200, Triton, or Montero Sport).

2. **Proven Reliability (When in Good Condition)**

The **4D56T** (turbocharged) and **4D56** (naturally aspirated) are robust diesel engines known for durability, especially when properly maintained. Many units have lasted well over 300,000 km (186,000 miles) with basic upkeep.

3. **Easier Availability Than OEM Parts**

Mitsubishi discontinued the 4D56 series years ago, making new OEM engines and cylinder heads nearly impossible to find. A used/open-box unit provides a practical solution for those needing a replacement.

4. **Potential for Performance Modifications**

The 4D56 platform is popular among diesel enthusiasts for tuning, including turbo upgrades, fuel system modifications, and head porting. A used cylinder head in good condition can be a cost-effective starting point for such projects.

5. **Compatibility with Aftermarket Support**

Since the engine is widely used, aftermarket parts (e.g., gaskets, bolts, sensors) and tuning services are readily available. This makes repairs and upgrades more straightforward than with rare or discontinued engines.

6. **Potential for Long-Term Use with Proper Care**

If the cylinder head and engine are in good structural condition (no cracks, warping, or excessive wear), they can serve reliably for many more years with regular maintenance, including valve adjustments, fuel system cleaning, and cooling system checks.

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1. **Unknown Service History and Wear**

Without a full service record, it s impossible to guarantee the condition of internal components like valves, seats, camshaft lobes, or piston rings. Hidden issues (e.g., cracked valves, worn turbo bearings) could lead to costly failures down the line.

2. **Risk of Hidden Damage**

- **Warped cylinder heads** (from overheating or poor cooling).

- **Leaking gaskets** (head gasket, oil pan, or turbo seals).

- **Worn or broken valves/seats** (leading to compression loss or oil burning).

- **Turbocharger failure** (if the 4D56T is involved, a worn turbo can cause catastrophic engine damage if it fails).

3. **Potential for Incompatible Modifications**

If the engine has been previously modified (e.g., with aftermarket turbos, injectors, or fuel pumps), these changes may not be compatible with the buyer s intended use. Without proper documentation, this can lead to performance issues or voided warranties on aftermarket parts.

4. **Limited Warranty or No Guarantee**

Open-box or used engines typically come with **no warranty** or only a short return window (if any). This shifts all risk to the buyer, who must cover repair costs if issues arise.

5. **Compatibility Issues with Modern Vehicles**

While the 4D56 fits older Mitsubishi models, newer vehicles may require additional modifications (e.g., wiring harnesses, ECU programming, or emissions compliance) to integrate the engine properly. This adds complexity and cost.

6. **Environmental and Emissions Concerns**

The 4D56 is an older diesel design with higher emissions than modern standards. In regions with strict emissions regulations, running it may require modifications (e.g., DPF deletion, EGR removal) or could be illegal without proper compliance.

7. **Potential for Higher Long-Term Costs**

If the engine is not in pristine condition, repairs (e.g., valve job, turbo replacement, head resurfacing) can be expensive. In some cases, it may be cheaper to source a different engine or rebuild the existing one from scratch.

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1. **What is the exact condition of the cylinder head?**

- Has it been resurfaced? Are there cracks or warping?

- Are the valve seats and guides in good condition?

2. **Has the engine been rebuilt or modified?**

- If yes, what changes were made? (e.g., turbo, injectors, fuel pump)

3. **What is the service history?**

- Oil changes, valve adjustments, cooling system flushes, turbo maintenance?

4. **Are there any known issues with this specific unit?**

- Has it had oil leaks, overheating, or turbo failures?

5. **Is there a warranty or return policy?**

- If not, what is the seller s refund/return process?

6. **Does the engine run smoothly, or are there signs of trouble?**

- Listen for unusual noises (knocking, rattling, whining from the turbo).

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- **Budget-conscious buyers** who need a replacement engine for an older Mitsubishi and cannot afford a new OEM unit.

- **Diesel enthusiasts** willing to inspect the engine thoroughly and invest in maintenance or modifications.

- **Restoration projects** where the engine is being rebuilt or heavily modified anyway.

- You need a **guaranteed, low-risk** replacement with minimal future costs.

- You lack mechanical knowledge or access to proper diagnostic tools.

- The engine is being purchased **without inspection** (always test-run and inspect visually).

- You plan to use the vehicle in **high-stress conditions** (towing, heavy loads) without verifying structural integrity.

1. **Inspect it thoroughly** Look for warping, cracks, leaks, and listen for unusual noises.

2. **Test-run it** Ensure it starts easily, runs smoothly, and doesn t exhibit smoke (blue oil burn, black fuel-rich).

3. **Get a compression test** Low compression in one or more cylinders indicates worn valves or rings.

4. **Consider a professional inspection** A diesel mechanic familiar with the 4D56 can spot hidden issues.

5. **Budget for potential repairs** Allocate extra funds for a valve job, turbo replacement, or head resurfacing if needed.

6. **Document everything** Take photos, notes, and a written description of the engine s condition before purchase.

- **Rebuilt 4D56 engines** (from reputable rebuilders like **Dynomax, Diesel Power Specialties, or local diesel shops**).

- **Used 4D56 engines with full service records** (more expensive but lower risk).

- **Alternative diesel engines** (e.g., **4JZ, 4M40, or 4J53** if compatibility allows).

Buying an open-box or used **KO KO58963S 4D56/4D56T cylinder head** can be a **cost-effective solution** if you re prepared for potential risks and willing to invest time in inspection and maintenance. However, it is **not a risk-free purchase**, and buyers should approach it with caution, prioritizing thorough due diligence. For those without mechanical experience, consulting a diesel specialist before committing is strongly advised.

Details:

These Parts Do NOT Have a Factory Warranty. 1 X Assembled Aluminum Cylinder Head. OPEN-BOX Performance 4D56T/4D56 Diesel Engine Assembled Cylinder Head Mitsubishi. When rebuilding a engine, cylinder head can cost lot of time and money from parts labor.

Brand New Cylinder Head New Carmen Valves NEW Valve Guides NEW Stem Seals NEW Seats NEW Springs Retainers All Built to Original Factory Specifications. Fits Vehicles with 4D56 Engines. It is measured for exact clearances and fully assembled ready to be installed. A new cylinder head can save on both.

part #: ko58963s prices

• $159.99-$292.49

specifications cylinderheapar:

• for makes: Mitsubishi
• brand: Ko Speed
• mpn: Ko58963s
• part type: Box Engine Cylinder Head
• california prop 65 warning: This Product Contains Chemicals Known To The State.
• style: Oe / Assembled Head
• materials: Cast Aluminum / Steel
• finish: Assembled
• notes: Open Box Item; Ships In Original Factory Packaging

returns cylinderheapar:

• policy: No Returns

general cylinderheapar:

• Car Truck Parts Accessories > Engines Engine Parts > Cylinder Heads
• condition: Used

offer cylinderheapar:

• sold: 0
• availability: In Stock
• quantity: 1
• started: February 10, 2026
• options: Ship-to-home

payments cylinderheapar:

• credit card: Visa
• other
• wallet: Paypal

shipping cylinderheapar:

• class: Standard
• cost: $0.00
• service: FedEx Ground / FedEx Home Delivery
• transit: 2-7 Days
• type: Fixed
• carrier: FedEx

seller cylinderheapar:

• city: City of Industry, CA
• rating: 99.4%
• # reviews: 36788