GATES SX-5491 Fuel Tank Cap 4.1L 4.8L 5.0L 5.7L

( Brand: Gates ), ( Manufacturer Part Number: SX-5491 ), ( Type: Fuel Tank Cap ), ( Placement On Vehicle: Air Fuel Delivery Hardware Fasteners Fittings ), ( Item Width: 3.630 ), ( Item Height: 3.000 ), ( Manufacturer Warranty: Recommended Service Interval ), ( Ipn: C703 57-46 ), ( Compatible Model: C20 Pickup ), ( Compatible Year: 1974 1973 ), ( Core Charge: Free No Core Charge ), ( Fitment Type: Direct Replacement ), ( Bundle Description: 1 Pc Genuine Gates Fuel Tank Cap )

Review GATES Fuel Tank Cap Chevrolet Pickup 4.1l 4.8l 5.0l 5.7l Nj fits C20 1973–1974

The **Gates SX-5491 Fuel Tank Cap** is a meticulously engineered, high-performance replacement part designed specifically for the classic 1973 1974 Chevrolet C20 pickup trucks equipped with the legendary **4.1L (250 CID) inline-six, 4.8L (292 CID) V8, 5.0L (305 CID) V8, or 5.7L (350 CID) V8 engines**. Crafted to meet the demands of both restoration enthusiasts and daily drivers, this cap ensures a secure, vapor-tight seal while maintaining the original aesthetic and functionality of your vehicle. Made from durable **polypropylene resin**, the SX-5491 features a robust, tamper-resistant design that prevents accidental opening during transit, reducing the risk of fuel spills or contamination. The cap s **precision-molded threads** and **recessed gasket** create a reliable seal, minimizing fuel vapor escape and ensuring optimal fuel system performance critical for maintaining engine efficiency and preventing emissions-related issues. Beyond its technical superiority, the Gates SX-5491 also pays homage to the era s design with its **chrome-plated finish**, offering a polished, vintage look that complements the C20 s rugged yet refined appearance. Whether you re restoring a show-worthy classic or simply upgrading a daily driver, this cap delivers the perfect blend of performance, durability, and authenticity, ensuring your fuel system operates smoothly while preserving the integrity of your vehicle s heritage.

### Pros and Cons of buying a Gates SX-5491 Fuel Tank Cap for a 1973-1974 Chevrolet C20 (4.1L, 4.8L, 5.0L, 5.7L)

1. **OEM Fitment and Compatibility** The Gates SX-5491 is designed specifically for the 1973-1974 Chevrolet C20 series trucks with the listed engine sizes. This ensures a proper fit without modifications, reducing the risk of leaks or improper sealing.

2. **High-Quality Materials** Gates is a well-known brand in automotive aftermarket parts, known for durable materials and reliable construction. The cap is likely made from sturdy plastic and features a secure sealing mechanism to prevent fuel vapors from escaping.

3. **Prevents Fuel Evaporation and Theft** A properly sealed fuel cap helps maintain fuel integrity by reducing evaporation, which is especially useful in older vehicles prone to fuel system issues. It also deters fuel theft by making it harder to remove the cap without the correct tool.

4. **Easy Installation** Since it s a direct replacement, installation is straightforward no modifications to the fuel tank or surrounding components are required. Most users can replace it themselves with basic tools.

5. **Compatibility with Modern Standards** While older vehicles may not have strict emissions requirements, a well-sealed cap helps meet basic fuel system integrity standards, which can be beneficial for long-term reliability.

6. **Affordable and Widely Available** Compared to OEM replacements, aftermarket options like the Gates SX-5491 are often more budget-friendly while still offering good quality. They can be found at most auto parts stores or online retailers.

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1. **Potential for Counterfeit or Low-Quality Replacements** Since Gates parts are widely available, there is a risk of purchasing a counterfeit or inferior knockoff, especially if buying from untrusted sellers. Always verify the seller s reputation and product authenticity.

2. **Stiffness or Wear Over Time** Older vehicles may have fuel tanks with slightly worn or corroded threads, which could make installation difficult or cause the cap to loosen over time. If the tank threads are damaged, the cap may not seal properly.

3. **Limited Customization** Unlike some modern fuel caps, this Gates model is a standard replacement with no additional features (e.g., locking mechanisms, pressure relief valves beyond what s standard). If you need extra security, you may need to add a separate lock.

4. **Possible Incompatibility with Aftermarket Mods** If the truck has been modified with an aftermarket fuel system (e.g., larger tanks, custom lines), the original cap may not fit perfectly. However, for stock or minor modifications, this should not be an issue.

5. **No Warranty on Used or Third-Party Purchases** If buying from a used or non-authorized seller, the warranty (if any) may be void. Gates typically offers warranties on new, direct purchases, so always check the terms.

6. **Potential for Over-Tightening** If not installed correctly, over-tightening the cap can strip the threads on the fuel tank, leading to leaks. It s important to tighten it securely but not excessively.

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The Gates SX-5491 fuel tank cap is a solid choice for a 1973-1974 Chevrolet C20 due to its OEM fitment, reliability, and ease of installation. It addresses common issues like fuel evaporation and theft while maintaining compatibility with the vehicle s stock setup. However, buyers should be cautious of counterfeit products, ensure the fuel tank threads are in good condition, and avoid over-tightening during installation.

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

- **Inspect the fuel tank threads** before installation to ensure they are clean and undamaged. Use thread-chaser if necessary.

- **Tighten the cap securely but not excessively** hand-tighten first, then give a quarter-turn with a wrench if needed.

- **Consider adding a fuel cap lock** if theft is a concern, as the standard cap does not include one.

- **Check for leaks** after installation by filling the tank and observing for any fuel odors or drips around the cap.

For most owners, the Gates SX-5491 is a practical and cost-effective solution that improves fuel system integrity without major drawbacks. If budget allows, pairing it with a fuel stabilizer (especially if the vehicle is stored long-term) can further enhance reliability.

Details:

Gates Fuel Tank Cap for 1973-1974 Chevrolet C20 Pickup 4.1L 4.8L 5.0L 5.7L nj: Status: In Stock.

part #: sx5491 prices

• $25.07-$34.49

specifications fueltanksysteme:

• for makes: Chevrolet
• for years: 1973-1974
• brand: Gates
• mpn: Sx-5491
• type: Fuel Tank Cap
• placement on vehicle: Air Fuel Delivery Hardware Fasteners Fittings
• item width: 3.630
• item height: 3.000
• manufacturer warranty: Recommended Service Interval
• ipn: C703 57-46
• compatible model: C20 Pickup
• compatible year: 1974 1973
• core charge: Free No Core Charge
• fitment type: Direct Replacement
• bundle description: 1 Pc Genuine Gates Fuel Tank Cap

payments fueltanksysteme:

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

seller fueltanksysteme:

• city: Indianapolis, Indiana
• # reviews: 660727
• rating: 99.6%

general fueltanksysteme:

• condition: New
• Car Truck Parts Accessories > Air Fuel Delivery > Fuel Tanks Filler Necks

shipping fueltanksysteme:

• transit: 4-6 Days
• class: Standard, Expedited
• cost: $0.00
• service: Standard, Expedited
• type: Fixed

offer fueltanksysteme:

• options: Ship-to-home
• sold: 0
• quantity: 10
• availability: In Stock
• started: May 24, 2026

returns fueltanksysteme:

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

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