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Choosing the Right Spark Plugs for Your 1964-1968 Ford Country Squire

Keep your classic wagon running smoothly with the correct set of spark plugs for its specific engine.

3 minutes to read 1964-1968 Ford Country Squire
Difficulty
1/5
Est. Time
1 hrs
DIY Doable?
✅ Yes
Shop Labor
$100-$150
⚠️ Drivable, but... — You can drive with old spark plugs, but it can lead to poor fuel economy, sluggish performance, and potential engine misfires.
Key Takeaways
  • Standard copper spark plugs from brands like Autolite, Champion, or NGK are the best choice for these vintage engines.
  • Always check which engine your Country Squire has (e.g., 289, 352, 390 V8) to get the correct spark plugs.
  • Before installation, it is critical to check and adjust the spark plug gap to your engine's specifications, typically around 0.035 inches.
  • Replacing spark plugs is an easy and affordable DIY job on these cars that can significantly improve engine performance and reliability.
The spark plugs in your Ford Country Squire are a key part of the ignition system. They take a high-voltage electrical signal from the ignition coil and create a spark. This spark ignites the mix of air and fuel inside the engine's cylinders. For the various V8 and inline-6 engines available in the 1964-1968 models, having clean, properly gapped spark plugs is essential for reliable starting, smooth running, and efficient power.

Signs of Failing Spark Plugs

Worn or fouled spark plugs can cause a number of noticeable engine problems. If your Country Squire is experiencing these issues, it might be time for a new set of plugs.

Common Symptoms:

  • Rough Idling: The engine may sound jittery or rough when the car is stopped, and you might feel vibrations.
  • Engine Misfires: You may feel the engine hesitate or sputter, especially during acceleration. This happens when a cylinder fails to fire correctly.
  • Difficulty Starting: While a weak battery is a common cause, worn spark plugs can also make it hard for the engine to turn over and start.
  • Poor Acceleration: If your wagon feels sluggish or has lost its usual power, it could be due to ineffective sparks from old plugs.
  • Reduced Fuel Economy: Fouled or improperly gapped plugs lead to inefficient fuel burning, meaning you'll make more trips to the gas station.

Choosing the Right Aftermarket Spark Plugs

For a classic vehicle like the 1964-1968 Country Squire, you don't need expensive, modern plugs. Standard copper core spark plugs are an excellent and affordable choice that matches the original technology of the vehicle. Ford originally used Autolite plugs, and they remain a solid choice for a factory-equivalent replacement.

Brand Tiers for Your Country Squire:

  • OEM Equivalent (Good): Autolite and Motorcraft are the go-to brands. Since Ford owned Autolite for a time, their copper plugs are often considered the original equipment for these engines. They offer reliable performance for stock ignition systems.
  • Standard Aftermarket (Good): Champion and Denso are also strong contenders. Champion's Copper Plus line is widely available and suitable for these vintage Ford engines. Denso's U-Groove plugs are another reliable option that fits these models.
  • Performance Aftermarket (Better): NGK is a highly respected brand among many classic car owners. While their standard copper plugs are excellent, they also offer options that can be beneficial if you have an upgraded ignition system, like one from MSD.

Pro Tip: The most important factor is getting the right plug for your specific engine. The Country Squire was offered with several engines, including the 289, 352, 390, and 427 V8s, as well as inline-6 options. Always verify the part number and, most importantly, check and adjust the spark plug gap before installation using a gapping tool. A common gap setting for these engines is 0.035 inches, but always check the specification for your particular engine.

Known Issues, Recalls, or TSBs

There are no specific recalls or Technical Service Bulletins (TSBs) from the National Highway Traffic Safety Administration (NHTSA) regarding spark plugs for the 1964-1968 Ford Country Squire. Any issues today are related to normal wear and tear. Some later model Ford engines (from the late 1990s and 2000s) had TSBs issued for spark plugs breaking or stripping threads, but these do not apply to the 1960s-era engines in your Country Squire.

Frequently Asked Questions (FAQ)

Do I need expensive iridium or platinum plugs for my classic Country Squire?

No. Standard copper core plugs are the best choice. The engines from this era were designed for them. More expensive plugs for modern cars won't offer any benefit and may not perform as well in this application.

What is a spark plug 'gap' and why is it important?

The gap is the small space between the center and ground electrodes at the tip of the plug. The size of this gap determines the size of the spark. An incorrect gap can lead to misfires and poor performance. Always check and set the gap on new plugs before installing them.

How often should I change the spark plugs?

For standard copper plugs in a classic car, a good interval is every 20,000 to 30,000 miles, or if you notice any of the failure symptoms. Given the age of the vehicle, it's a good idea to inspect them annually.

Is replacing spark plugs a difficult DIY job on this car?

No, this is a great DIY project for a beginner. 🎬 Watch this step-by-step guide on changing spark plugs in classic cars. The engines in the 1964-1968 Country Squire have easy access to the spark plugs, unlike modern cars. You will need a ratchet, a spark plug socket, and a gapping tool.

How to Change Spark Plugs in a Classic Car
How to Change Spark Plugs in a Classic Car

Technical Specifications

OEM Part Numbers: B5C-12405-A

Engine-dependent. Common plugs are Autolite 3924, Champion 22 (RF11YC), or equivalent. Most require a 0.035" gap, tapered seat, and 13/16" or 5/8" hex size. Always verify based on your specific engine.

Wrenchy
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The information in this article is provided for general reference and educational purposes only. Vehicle specifications, procedures, and part compatibility can vary by production date, trim level, and region. Always consult your vehicle's factory service manual and verify part numbers before purchasing or performing repairs. Safety-critical components such as airbags, seat belts, and braking systems should be installed by a qualified professional.

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