What size is the thread on an oil filter?
The thread on the most common spin-on oil filters is 3/4-16 UNF, but there are important variations by make and region. In practice, you’ll most often need 3/4-16 UNF, while many European cars use metric threads such as M20x1.5. Always verify for your specific vehicle.
Most Common Thread Size
The vast majority of passenger cars—especially in the United States and many imports—use a standard 3/4-16 UNF thread on the oil filter. This size is widely supported by aftermarket filters and cross-reference catalogs.
- 3/4-16 UNF: diameter about 0.75 inches, 16 threads per inch; the standard for many spin-on filters.
- Metric alternatives seen on some European vehicles: M20x1.5 and occasionally M22x1.5; these require a corresponding filter with the matching metric thread.
Having the correct thread size is essential to prevent leaks and ensure proper seating. If your vehicle is not covered by the 3/4-16 UNF standard, it will typically be specified in the owner's manual or on the filter packaging.
How to Identify the Thread Size for Your Vehicle
To determine the exact thread size for your oil filter, use these verification steps before purchasing a replacement.
- Check the owner's manual or the vehicle’s parts catalog for the recommended oil filter part number and its thread size.
- Inspect the filter itself: many filters have the thread size stamped on the base or side of the can.
- Compare with the old filter: take the removed filter to an auto parts store to match the thread, or measure the diameter and count threads per inch.
- When purchasing online, read the product listing carefully to confirm it specifies 3/4-16 UNF or the exact metric size (for example, M20x1.5).
Accurate identification prevents cross-compatibility errors, leaks, and installation issues. If in doubt, consult a professional or reference the OEM cross-reference guide.
Conclusion
In most vehicles, the oil filter thread will be 3/4-16 UNF, a universal standard in many markets. Some European and certain import vehicles use metric threads such as M20x1.5. Always verify using the vehicle’s manual, the filter you’re replacing, or the cross-reference information from the parts supplier to ensure the correct fit. Using the right size is crucial for a proper seal and reliable engine protection.
Summary: The dominant thread size for oil filters is 3/4-16 UNF, with metric alternatives like M20x1.5 appearing on some European vehicles. Identify the exact size via the manual, the filter itself, or a reliable parts catalog to avoid leaks and fit issues.
What is the thread on a standard oil filter?
The most common oil filter thread sizes are 3/4"-16 (standard) and M20 x 1.5 (metric). However, other common sizes exist, such as 13/16"-16 and 5/8"-18. It's crucial to confirm the exact size for your vehicle before purchasing a filter to avoid damage, as using the wrong size can cause leaks or a sudden loss of oil pressure.
Common thread sizes
- 3/4"-16: A widely used standard size, often found on American-made vehicles.
- M20 x 1.5: The most common metric thread size.
- 13/16"-16: Another standard size, sometimes found on different engines.
- 5/8"-18: A less common size, but still used on certain engines, particularly some European and classic British cars.
How to find your car's oil filter size
- Check the old filter: Look for a part number or thread size printed on the old filter.
- Use an open-end wrench: If you can't find a size on the old filter, try slipping a 3/4" open-end wrench over the mounting threads. If it fits, you likely have a 3/4"-16 filter. If not, you may have a metric thread.
- Consult your vehicle's manual: Your owner's manual will specify the correct oil filter size and part number for your car.
What size is a filter thread?
To filter thread size, check the front of your lens or lens cap for a circle with a horizontal line through it, followed by a number (e.g., Ø67mm). This number is the filter diameter in millimeters and must match the size of the filter you buy to ensure a proper fit without vignetting. For multiple lenses, it's often more economical to buy one large filter and use step-up rings to adapt it to smaller lenses.
How to find and use filter thread size
This video explains how to find your camera's filter thread size: 55sPolarProYouTube · Sep 21, 2023
- Find the size on your lens: Look for a symbol that looks like a circle with a line through it (Ø) followed by a number, such as Ø58mm or Ø77mm. This marking is often on the front of the lens itself, or sometimes printed on the lens cap.
- Match the filter to the lens: The number you find is the filter diameter you need. You must purchase a filter with the exact same millimeter (mm) measurement to ensure it screws on correctly.
- Understand common sizes: Common filter sizes include 49mm, 52mm, 58mm, 62mm, 67mm, 72mm, 77mm, and 82mm, though your lens may have a different size.
- Use step-up/step-down rings:
- Step-up rings: Allow you to use a larger filter on a smaller lens. This is a useful option to save money if you have several lenses with different sizes by only buying one large filter and a few rings.
- Step-down rings: Allow you to use a smaller filter on a larger lens. However, using a step-down ring that is smaller than one or two sizes can cause the filter to block light and create dark corners (vignetting) in your photos, so they should be avoided if possible.
- Avoid "stacking" filters if possible: While some filters have threads on the front to allow another filter to be attached ("stacked"), this can lead to undesirable effects like ghosting.
Are all oil filters the same thread?
No. There are 4 different dimensions, Thread size/pitch, the seal diameter, the overall diameter, and the height or depth of the filter.
How to measure oil filter thread size?
Use a caliper or a ruler to measure the distance across the filter. This measurement will give you a good indication of the size of the wrench you need. Make sure to measure accurately to avoid any misfits.
