What Size Wrench For Oil Change

So, you're tackling an oil change and want to make sure you have the right tools. Excellent! Using the correct wrench for your oil filter and drain plug is critical to avoid damaging components and ensuring a successful oil change. This guide will dive deep into what size wrench you need, why it matters, and other essential considerations for your DIY oil change.

Purpose: Why Getting the Right Wrench Matters

Using the correct size wrench for an oil change is paramount for several reasons:

Preventing Damage: Using the wrong size wrench can lead to rounding off the corners of the oil filter or drain plug. Once rounded, they become incredibly difficult, sometimes impossible, to remove without specialized tools or causing further damage. This can turn a simple job into a major headache.
Proper Torque: Many drain plugs require specific torque settings (the amount of rotational force applied when tightening). Using the correct wrench allows you to accurately apply this torque with a torque wrench, preventing leaks or over-tightening that could damage the drain plug or oil pan threads.
Safety: A slipping wrench can cause injury. A properly fitting wrench provides a secure grip, minimizing the risk of slips and potential hand or arm injuries.
Efficiency: The right tool makes the job faster and smoother. You won't be fighting with ill-fitting wrenches, saving you time and frustration.

Key Specs and Main Parts: Oil Filters and Drain Plugs

Two primary components determine the wrench sizes you'll need:

Oil Filter

Oil filters come in various sizes and shapes. While some can be loosened by hand (when installing, you should always hand-tighten them), most require a specialized oil filter wrench. There are several types:

Cap-Type Wrenches: These are designed to fit over the end of the oil filter, providing a secure grip. They come in various sizes to match specific filter diameters.
Band-Type Wrenches: These feature a metal or nylon band that wraps around the filter. As you turn the wrench, the band tightens, gripping the filter. These are more versatile for different filter sizes but can be less secure than cap-type wrenches.
Pliers-Type Wrenches (Oil Filter Pliers): These adjustable pliers are designed to grip oil filters. While versatile, they can sometimes damage the filter casing if too much force is applied.

Finding the Right Size: The best way to determine the correct size cap-type wrench is to consult your vehicle's owner's manual or a reputable auto parts store. They can cross-reference your vehicle's year, make, and model to the specific oil filter required and the corresponding wrench size. Common sizes are in the range of 64mm, 74mm, 76mm, 86mm and 93mm.

Oil Drain Plug

Oil drain plugs are typically hexagonal (six-sided) or occasionally square. The size is measured as the distance across the flats of the hexagon or square.

Common Sizes: Oil drain plug sizes vary widely depending on the vehicle. Common sizes include 13mm, 14mm, 15mm, 16mm, 17mm, and 19mm. Some vehicles may use metric sizes, while others use SAE (Society of Automotive Engineers) sizes (e.g., 1/2 inch, 9/16 inch). Always use a metric wrench on a metric bolt and an SAE wrench on an SAE bolt. Using the wrong type can easily strip the bolt head.

Finding the Right Size: The easiest way to determine the correct size is to refer to your vehicle's owner's manual. If the manual doesn't specify the size, you can try different wrenches until you find one that fits snugly without any play. You can also use a socket set to quickly test various sizes.

Symbols: Reading Wrench Sizes

Wrench sizes are typically marked directly on the wrench. Understanding these markings is crucial:

Metric: Metric wrench sizes are indicated in millimeters (mm). For example, "17mm" means the wrench is designed for a 17-millimeter bolt or nut.
SAE: SAE wrench sizes are indicated in fractions of an inch. For example, "9/16" means the wrench is designed for a 9/16-inch bolt or nut.
Torque Markings (On Torque Wrenches): Torque wrenches display torque values in units like Newton-meters (Nm) or foot-pounds (ft-lbs). These values indicate the amount of rotational force being applied.

How It Works: The Mechanics of Wrenching

The basic principle behind using a wrench is simple: apply leverage to turn a fastener (bolt, nut, or filter). However, understanding the nuances can prevent damage:

Proper Fit: Ensure the wrench fits snugly on the fastener. Any play indicates an incorrect size, which can lead to rounding.
Applying Force: Apply force smoothly and evenly. Avoid jerking or excessive force, which can damage the fastener or the wrench.
Torque Wrench Use: When tightening the drain plug, use a torque wrench to apply the manufacturer's recommended torque specification. Overtightening is a common mistake that can damage the oil pan threads. Set the torque wrench to the specified value and tighten the drain plug until the wrench "clicks," indicating that the desired torque has been reached.
Filter Tightening: Always hand-tighten your oil filter when installing. Follow the instructions on the filter, usually requiring you to tighten a certain number of turns after the filter gasket makes contact with the engine block.

Real-World Use: Troubleshooting Tips

Even with the right tools, problems can arise. Here are some troubleshooting tips:

Stuck Oil Filter: If the oil filter is stuck, try using a band-type wrench or oil filter pliers. If those don't work, consider using a screwdriver to puncture the filter and use it for leverage (be careful of hot oil!).
Rounded Drain Plug: If the drain plug is rounded, try using a specialized rounded bolt extractor. These tools are designed to grip damaged fasteners. As a last resort, you may need to weld a nut onto the drain plug to provide a new gripping surface.
Leaking Drain Plug: If the drain plug is leaking, check the crush washer. Replace the crush washer with a new one each time you change the oil. Also, make sure you're using the correct torque specification.
Cross-Threaded Drain Plug: If the drain plug feels difficult to tighten or loosens strangely, it might be cross-threaded. Do not force it. This is a serious problem that may require repairing the oil pan threads with a thread repair kit (e.g., Heli-Coil) or replacing the oil pan.

Safety: Proceed with Caution

Oil changes involve working with hot components and potentially hazardous fluids. Always prioritize safety:

Hot Oil: Allow the engine to cool down before draining the oil to prevent burns.
Jack Stands: Never work under a vehicle supported only by a jack. Always use jack stands for support.
Eye Protection: Wear safety glasses to protect your eyes from splashes of oil or debris.
Gloves: Wear gloves to protect your hands from oil and grease.
Proper Disposal: Dispose of used oil and filters properly at a designated recycling center.

Conclusion

Choosing the right wrench for your oil change is a crucial step for a successful and safe DIY project. By understanding the different wrench types, sizes, and their applications, you can prevent damage, ensure proper torque, and streamline the entire process. Remember to always consult your vehicle's owner's manual and prioritize safety. With the right tools and knowledge, you can confidently tackle your next oil change.

We have a detailed diagram illustrating common wrench sizes and oil filter types available. Please reach out if you'd like to download it.