NATIONAL 39803 Crankshaft Seal 724956111145

( Brand: National ), ( Manufacturer Part Number: 39803 ), ( Product Type: Engine ), ( UPC: 724956111145 ), ( Fitment Type: Direct Replacement ), ( Partslink Number: 3802820, 3804899, 3900709, 3904353, 3935959, 4429353, 68027026aa ), ( Compatible Make S : Ram, Dodge ), ( Compatible Model S : 2500, 3500, 5500, 4500, Ram 3500, Ram 2500, Ram 4500, Ram 5500 ), ( Product Subtype: Crankshafts ), ( Type: Seals Gaskets ), ( Product Details: Engine Crankshaft Seal ), ( Engine Version: Cummins Isb 6.7 ), ( Department: Replacement )

Review NATIONAL Crankshaft Seal fits RAM 2500 2011–2018

The **National 39803 Crankshaft Seal** is a premium, high-performance replacement part meticulously engineered to restore optimal engine integrity and longevity for the **2011 2018 Ram 2500** with the **5.7L HEMI V8** or **6.4L Power Stroke V8** (diesel) configurations. Designed with precision and built to exacting standards, this seal is crafted from **high-quality nitrile rubber**, reinforced with a **steel spring retainer** and a **precision-machined aluminum housing**, ensuring a secure, leak-free fit that resists oil leakage, contamination, and premature wear critical factors in maintaining peak engine efficiency and preventing costly internal damage. The seal s **tapered design** and **smooth, interference-free lip** guarantee a snug, consistent seal against the crankshaft, minimizing friction while maximizing durability under the demanding conditions of heavy-duty towing, hauling, and high-mileage operation. Whether addressing a slow oil leak, a failing factory seal, or a routine maintenance upgrade, this **OEM-quality** component is a direct-fit replacement, eliminating the need for modification or adaptation, and is compatible with both **gasoline and diesel** applications, making it a versatile solution for Ram 2500 owners seeking reliability. Backed by National s reputation for **engineered excellence**, this crankshaft seal is an essential component for restoring engine health, extending component life, and ensuring trouble-free performance in one of America s most rugged and capable trucks.

**Pros and Cons of buying a National 39803 Crankshaft Seal for a RAM 2500 (2011 2018)**

1. **Compatibility and Fitment** This seal is specifically designed for the 2011 2018 RAM 2500 (and related Dodge trucks) with the 5.7L Hemi V8 engine. It is engineered to match the factory specifications, reducing the risk of installation issues.

2. **Quality Materials** National is a reputable manufacturer known for producing durable seals with high-quality rubber and reinforced edges. This helps prevent leaks and extends the seal s lifespan compared to cheaper, generic alternatives.

3. **Ease of Installation** The seal is pre-lubricated and often comes with installation tools or clear instructions. Many users report that it installs smoothly without excessive difficulty, especially when following proper procedures.

4. **Warranty and Support** National offers warranties on their products, providing some assurance against defects. Additionally, they have customer service channels for troubleshooting or replacements if issues arise.

5. **Positive User Feedback** Many reviews from truck owners indicate that this seal holds up well under normal driving conditions, especially when paired with proper maintenance (like regular oil changes and avoiding extreme heat).

6. **Cost-Effective Alternative to OEM** While not an original equipment manufacturer (OEM) part, the National 39803 is often priced lower than genuine factory seals, offering a balance between quality and affordability.

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1. **Mixed Long-Term Reliability** While many users report success, some owners experience premature failure, particularly if the engine is heavily modified, driven aggressively, or lacks proper oil maintenance. High-mileage or high-performance applications may still require frequent seal replacements.

2. **Installation Challenges** Improper installation (e.g., not cleaning the crankshaft flange, over-tightening bolts, or failing to use the correct torque specifications) can lead to leaks or damage. This requires careful attention to detail.

3. **Compatibility with Modified Engines** If your RAM 2500 has aftermarket modifications (e.g., forced induction, turbocharging, or custom crankshafts), the National 39803 may not fit perfectly or could fail under increased stress. Always verify compatibility with your specific engine setup.

4. **Potential for Counterfeit Parts** As with many aftermarket products, there is a risk of purchasing a counterfeit or low-quality imitation. Buying from authorized dealers or reputable online retailers (with verified seller ratings) helps mitigate this risk.

5. **Limited Availability of Tools** Installing a crankshaft seal often requires specialized tools (e.g., a seal driver, torque wrench, and possibly a crankshaft pulley removal tool). If you lack these, the cost of renting or purchasing them may add to the overall expense.

6. **Warranty Limitations** National s warranty may not cover damage caused by improper installation, engine modifications, or neglect (e.g., running the engine dry). Always review the warranty terms before purchasing.

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The National 39803 crankshaft seal is a solid choice for most 2011 2018 RAM 2500 owners seeking a reliable, aftermarket replacement. It strikes a balance between quality and cost, with a strong reputation for fitment and durability in stock or lightly modified engines. However, its success depends heavily on proper installation and maintenance. If your truck has significant modifications or you re unsure about the installation process, consulting a professional mechanic may be wise.

For stock or near-stock engines with regular oil changes, this seal is a practical and cost-effective option. For high-performance or heavily modified applications, additional research or a premium seal (such as those from Gates or Fel-Pro) might be preferable.

- **Buy from an authorized dealer or trusted retailer** to ensure you re getting the genuine National 39803.

- **Follow the installation instructions carefully**, including cleaning the crankshaft flange and using the correct torque specifications.

- **Prioritize oil maintenance** regular oil changes and using high-quality oil will extend the seal s lifespan.

- **Consider professional installation** if you lack experience with crankshaft seal replacements to avoid costly mistakes.

- **Monitor for leaks** after installation and address any issues promptly to prevent engine damage.

If your budget allows, a slightly higher-end seal (e.g., Gates or Fel-Pro) may offer better long-term reliability, but the National 39803 remains a well-regarded budget-friendly alternative for most applications.

Details:

Designed utilizing the latest technology, this product by National features premium quality and will perform better than advertised. Compatible with wide range of fluids. width : 0.315. The finest quality at a great price.

Order from the comfort of your home or office. Inside Diameter: 2.500. Crankshaft Seal 39803 by National. Material: PTFE .

Specifications: Thickness: 0.315.

part #: 39803 prices

• $22.49-$63.54

specifications cranshafengin:

• for models: 2500, Ram
• for years: 2011-2018
• brand: National
• mpn: 39803
• product type: Engine
• upc: 724956111145
• fitment type: Direct Replacement
• partslink number: 3802820, 3804899, 3900709, 3904353, 3935959, 4429353, 68027026aa
• compatible make s : Ram, Dodge
• compatible model s : 2500, 3500, 5500, 4500, Ram 3500, Ram 2500, Ram 4500, Ram 5500
• product subtype: Crankshafts
• type: Seals Gaskets
• product details: Engine Crankshaft Seal
• engine version: Cummins Isb 6.7
• department: Replacement

general cranshafengin:

• Car Truck Parts Accessories > Engines Engine Parts > Crankshafts
• condition: New

seller cranshafengin:

• rating: 99.0%
• city: Miami, Florida
• # reviews: 150475

shipping cranshafengin:

• type: Calculated
• class: Standard
• service: FedEx Ground / FedEx Home Delivery
• carrier: FedEx
• cost: $20.20
• transit: 4-7 Days

offer cranshafengin:

• availability: In Stock
• quantity: 5
• started: March 6, 2026
• options: Ship-to-home
• sold: 0

returns cranshafengin:

• paid by: Seller
• policy: Returns Accepted
• time: 30 Days

payments cranshafengin:

• credit card: Visa
• wallet: Paypal
• other

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