NATIONAL 45TMTYZ78 Rear Crankshaft Seal Aerostar Contour

( Brand: National ), ( Manufacturer Part Number: 45TMTYZ78 ), ( Type: Crankshaft Seal ), ( Placement On Vehicle: Rear ), ( Fits 1: 1991-2008 Ford Ranger ), ( Fits 2: 1986-1997 Ford Aerostar ), ( Fits 3: 1995-2000 Ford Contour ), ( Fit Note: Engine Crankshaft Seal Ptfe Rubber Material ), ( Manufacturer Warranty: 12 Month Warranty ), ( Attention: Please Read All Notes To Confirm Fitment ), ( Cs-sku: 400 )

Review NATIONAL Rear Crankshaft Seal Aerostar Contour Exp fits RANGER ESCAPE ESCORT

The **National 45TMYZ78 Rear Crankshaft Seal** is a premium, high-performance replacement seal meticulously engineered to restore optimal functionality and longevity to the rear crankshaft area of select Ford vehicles, including the **Ranger, Aerostar, Contour, Escape, and Escort** models equipped with the **4.9L V8 (45TMYZ78) engine**. Crafted from durable **nitrile rubber with a reinforced steel spring**, this seal is designed to withstand the demanding pressures and temperatures generated by high-performance driving, ensuring a reliable barrier against oil leaks and contamination. The precision-molded design guarantees a perfect fit within the engine s crankshaft housing, minimizing friction and preventing premature wear, which is critical for maintaining engine efficiency and preventing costly internal damage. Whether addressing a slow oil leak, a replacement due to routine maintenance, or an upgrade for enhanced durability, this seal delivers exceptional sealing performance, reducing the risk of oil leaks that can compromise engine health and performance. Ideal for both professional mechanics and DIY enthusiasts, the **National 45TMYZ78** combines ease of installation with long-term reliability, making it a trusted choice for restoring and protecting the rear end of your Ford powertrain.

### Pros and Cons of buying a **National 45TMYZ78 Rear Crankshaft Seal for Ford Ranger, Aerostar, Contour, Escape, and Escort**

1. **Compatibility** The National 45TMYZ78 is specifically designed for the listed Ford models, ensuring a proper fit without modification. This reduces the risk of installation errors that could lead to leaks or damage.

2. **Quality Construction** National is a well-regarded brand in the automotive aftermarket, known for durable materials and reliable performance. Their seals are often made from high-quality rubber or elastomers that resist wear and temperature fluctuations.

3. **Ease of Installation** Since it s an OEM (Original Equipment Manufacturer) replacement part, it should align seamlessly with the existing components. This makes it easier for both professional mechanics and DIYers to install correctly.

4. **Cost-Effective Solution** Compared to purchasing an entire transmission or engine, replacing just the crankshaft seal is a far more affordable fix for leaks, which can save significant money in the long run.

5. **Prevents Further Damage** A failing crankshaft seal can lead to oil leaks, which may contaminate other systems (e.g., transmission fluid) or cause engine damage if ignored. Replacing it proactively can prevent costly repairs down the line.

6. **Warranty Coverage** Many reputable aftermarket parts, including National, come with warranties. This provides some assurance against defects or premature failure.

7. **Availability** As an aftermarket part, it is widely available through online retailers, auto parts stores, and even direct from National s distributors, making it easy to source.

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1. **Potential Counterfeit Risk** Since it s a popular part, there is a chance of purchasing a counterfeit or low-quality imitation, especially from untrusted sellers. Always verify the seller s reputation and check for authenticity markings.

2. **Installation Challenges** While designed for compatibility, improper installation (e.g., incorrect torque, misalignment, or improper sealing) can lead to leaks or premature failure. This may require professional help if the buyer lacks experience.

3. **Limited Longevity Compared to OEM** Some aftermarket seals may not last as long as genuine OEM parts, though high-quality brands like National mitigate this risk. Wear and tear depend on driving conditions and maintenance.

4. **Price Variability** Prices can fluctuate based on the seller, brand reputation, and whether it s a new or refurbished unit. Buyers should compare prices across multiple sources to ensure they re getting a fair deal.

5. **Compatibility with Modified Vehicles** If the vehicle has been modified (e.g., engine swaps, transmission upgrades, or aftermarket components), the seal may not fit perfectly. Always confirm compatibility with the specific application.

6. **Risk of Overlooking Underlying Issues** A leaking crankshaft seal might indicate other problems, such as a worn-out oil pan gasket, damaged transmission housing, or excessive engine wear. Replacing just the seal without addressing these could lead to recurring issues.

7. **Environmental Factors** Extreme temperatures, road debris, or poor maintenance (e.g., using low-quality oil) can accelerate seal wear, reducing its lifespan regardless of brand.

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The **National 45TMYZ78 rear crankshaft seal** is a solid aftermarket option for Ford Ranger, Aerostar, Contour, Escape, and Escort models. It offers a balance of compatibility, durability, and affordability, making it a practical choice for addressing leaks and preventing further damage. However, buyers should exercise caution to avoid counterfeit products, ensure proper installation, and consider the vehicle s overall condition to avoid recurring problems.

- **Buy from a trusted source** (e.g., RockAuto, Amazon with verified sellers, or a reputable local auto parts store) to avoid counterfeit parts.

- **Verify compatibility** with your exact vehicle model and year, especially if it has modifications.

- **Consider professional installation** if unsure about the process, as improper handling can void warranties or cause leaks.

- **Pair with a maintenance routine** (regular oil changes, checking for other leaks, and using high-quality oil) to maximize the seal s lifespan.

- **Compare prices** but prioritize quality over the lowest cost to ensure long-term reliability.

For most drivers, the National 45TMYZ78 is a **reliable and cost-effective replacement** that justifies its purchase for fixing crankshaft seal leaks. However, if budget allows, an OEM or high-end aftermarket seal (e.g., Fel-Pro) may offer slightly better longevity.

Details:

1981- 1985 Ford Escort 1.6L 4 Cl. Excellent dry running capabilities. Low coefficient of friction. 1985 1996 Ford Escort 1.9L 4 Cl.

Rear Crankshaft Seal 45TMTYZ78 for Ranger Aerostar Contour Escape Escort EXP: Position: Brand: National condition: New, Notes Engine PTFE Rubber Material Features: Design type: spring less; multi-lip. Delivers quality and reliable performance for every type of repair. Temperature range: 100F to 450F / 73C 232.

part #: 45tmtyz78 price

• $38.18

specifications cranshafengin:

• for models: Ranger, Escape, Escort
• brand: National
• mpn: 45tmtyz78
• type: Crankshaft Seal
• placement on vehicle: Rear
• fits 1: 1991-2008 Ford Ranger
• fits 2: 1986-1997 Ford Aerostar
• fits 3: 1995-2000 Ford Contour
• fit note: Engine Crankshaft Seal Ptfe Rubber Material
• manufacturer warranty: 12 Month Warranty
• attention: Please Read All Notes To Confirm Fitment
• cs-sku: 400

payments cranshafengin:

• credit card: Visa
• wallet: Google-pay
• other

offer cranshafengin:

• sold: 0
• started: May 6, 2026
• quantity: 1
• availability: In Stock
• options: Ship-to-home

general cranshafengin:

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

returns cranshafengin:

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

seller cranshafengin:

• city: Aurora, Colorado
• # reviews: 57801
• rating: 97.1%

shipping cranshafengin:

• transit: 2-6 Days
• service: Standard
• cost: $0.00
• type: Fixed
• class: Standard

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