A 64mm oil filter wrench is a socket-shaped tool that grips the metal canister of your oil filter so you can unscrew it by hand
Oil filters come in different sizes, and a 64mm wrench fits the most common size you'll encounter on passenger cars and light trucks. The wrench slides over the filter's rounded exterior, and the socket grips it firmly enough that you can turn it counterclockwise without the wrench spinning off. Without one, you're either wrestling with a filter by hand until your palms hurt, or you're using a rag or towel that often slips and wastes time.
The 64mm size is the industry standard for most vehicles made in the last 20 years. If you own one car and change its oil yourself, this is almost certainly the size you need — but you should confirm by looking at your filter or your owner's manual before you buy, because buying the wrong size means a wasted trip back to the store.
Key Takeaways
- A 64mm wrench fits the most common oil filter size on passenger vehicles and light trucks built since the early 2000s.
- The wrench grips the filter's exterior so you can unscrew it by hand without the tool spinning off or your hands slipping.
- You should confirm your filter size in your owner's manual or by looking at the filter itself before buying a wrench.
- A 64mm wrench costs between $8 and $25 depending on the brand and material, and one wrench lasts for many oil changes.
How a 64mm wrench grips and turns the filter
The wrench is a hollow metal socket with a diameter of 64 millimeters on the inside. You slide it over the top of the oil filter canister, which has a rounded metal exterior that the socket grips. The socket has small notches or ridges on the inside that bite into the filter's surface so it doesn't spin freely.
Once the wrench is seated on the filter, you turn it counterclockwise — the same direction you'd turn any bolt to loosen it. The wrench transfers your hand's turning force to the filter, and the filter unscrews from the engine block. When the filter is loose enough, you can finish unscrewing it by hand and lift it away.
The difference between 64mm and other common filter sizes
Oil filters come in several standard sizes, and the wrench must match the filter's diameter. A 64mm wrench will not fit a 76mm filter, and forcing it on will damage both the wrench and the filter. The most common sizes are 64mm, 74mm, and 86mm, with 64mm being the most frequent on smaller engines and older vehicles.
To find your filter size, check your owner's manual — it will list the filter part number and often the diameter. You can also look at the filter itself if it's already on the engine; the size is usually printed on the canister. If you're buying a replacement filter, the box will state the diameter.
Types of 64mm wrenches and what they cost
The most common type is a socket wrench, a hollow cylinder that slides over the filter. These are made from steel or aluminum, with steel being more durable and aluminum being lighter. A basic steel socket wrench costs between $8 and $15 and will last through dozens of oil changes.
A strap wrench is an alternative that uses a fabric or rubber strap instead of a socket. You wrap the strap around the filter and pull the handle to tighten it, then turn the handle to unscrew the filter. Strap wrenches work on multiple filter sizes and cost $10 to $20, but they require more hand strength and take longer to use.
A cartridge filter wrench is a different tool altogether — it's for filters that screw into the top of the engine rather than hanging from the side. If your vehicle has a cartridge filter, you need a cartridge wrench, not a socket wrench. Check your owner's manual to know which type your engine uses.
When you actually need a 64mm wrench versus alternatives
If you change your own oil, a 64mm wrench is worth buying once and keeping in your toolbox. It makes the job faster and easier, and it costs less than one oil change at a shop. You'll use it every time you change the filter, so the cost spreads across many uses.
If you only change your oil once every few years or you take your car to a shop, you may never need to buy one. Some people borrow a wrench from a friend or neighbor rather than buy their own. If you're changing oil for the first time and unsure whether you'll do it again, you can rent a wrench from some auto parts stores for a few dollars, or you can ask the store staff to help you unscrew the filter by hand before you leave.
A rag or towel wrapped around the filter can work in a pinch if the filter isn't too tight, but it often slips and wastes time. A socket wrench is faster and more reliable, especially if the filter was installed tightly or if you have small hands.
How to use a 64mm wrench safely and without damaging the filter
Before you start, make sure the engine is cool enough to touch — a hot filter can burn your hands. Slide the wrench over the filter until it seats firmly on the rounded exterior. You should feel it grip; if it slides around loosely, the wrench is the wrong size or the filter is damaged.
Turn the wrench slowly and steadily counterclockwise. Don't jerk it or explore sudden force, because that can strip the filter's exterior or crack the wrench. Once the filter is loose enough to turn by hand, remove the wrench and finish unscrewing it by hand. Wipe any spilled oil from the engine block with a rag before you install the new filter.
Frequently Asked Questions
What if I buy the wrong size wrench?
A wrench that's too large will slide around on the filter and won't grip it. A wrench that's too small won't fit over the filter at all. If you buy the wrong size, most auto parts stores will exchange it for the correct size if you have your receipt and the wrench is unused.
Can I use a 64mm wrench on a different size filter?
No. A 64mm wrench is designed to fit a 64mm filter only. Using it on a 74mm or 86mm filter will damage both the wrench and the filter. Always confirm your filter size before buying a wrench.
Do I need a wrench if I'm just replacing the filter at a shop?
No. The shop has wrenches and will remove and install the filter as part of the service. You only need a wrench if you're changing the oil yourself.
How do I know if my wrench is gripping the filter correctly?
The wrench should feel snug and not slide around when you turn it. If it spins freely or feels loose, remove it and check that it's the correct size for your filter. A loose wrench can slip off and damage the filter or your hands.