What size thread is a towing eye?
There is no single universal thread size for towing eyes. The correct size depends on the vehicle and the tow point. In modern passenger cars you’ll commonly encounter metric threads such as M12 x 1.25, M12 x 1.5, M14 x 1.5, or M16 x 1.5; larger or heavy‑duty applications can use M20 x 2 or even imperial sizes like 1/2"-13 UNC or 5/8"-18 UNC. Always check the vehicle’s manual or OEM tow eye kit for the exact specification.
Why thread size varies from car to car
Vehicle manufacturers design recovery points to specific load ratings and mounting geometries. Some cars hide the tow eye behind a bumper cover and insert a screw-in eye, while others use captive nuts or dedicated recovery points. The thread pitch and diameter must match the factory specification to ensure safe towing; using the wrong size can strip threads, fail under load, or damage mounting points. Regional standards also influence what thread is common, with metric threads dominating in Europe and Asia and certain older U.S. cars still using imperial sizes.
Common thread sizes you may encounter
The following sizes cover a broad range of modern passenger cars and light trucks. The sizes listed refer to the thread diameter and pitch of the mounting hole for the towing eye.
- M12 x 1.25
- M12 x 1.5
- M14 x 1.5
- M16 x 1.5
- M20 x 2
- 1/2"-13 UNC
- 5/8"-18 UNC
Note: This list is not exhaustive. Specific models may use different sizes. When in doubt, rely on OEM parts or the vehicle’s official documentation.
Notes for regional variations
In Europe and many parts of Asia, metric sizes prevail. In the United States and some older vehicles, imperial thread formats may appear. If possible, verify the exact specification with the dealer or by checking the VIN and the model’s service information.
How to verify the correct size for your vehicle
To confirm the exact thread size for your car’s towing eye, follow these steps:
- Consult the owner’s manual or service bulletin for the towing eye specification (including diameter and pitch).
- Inspect the current towing eye: measure the thread diameter with a caliper and determine the pitch (threads per unit length) using a thread gauge or by counting threads per centimeter.
- Compare measurements to common sizes and confirm against OEM part numbers; if the car uses a factory spare tow eye, bring the VIN to a dealer or parts store for verification.
- If replacing an eye, ensure the replacement matches both diameter and pitch and has the same load rating as the original.
- When installing, follow the manufacturer’s torque specification and seating instructions to avoid cross‑threading or loosening under load.
Proper verification prevents cross‑threading and ensures the towing eye performs safely under strain.
Safety and compatibility considerations
Always use a towing eye that matches the manufacturer’s specification and load rating. Do not improvise with improvised connectors or mismatched threads, as they can fail catastrophically. Inspect for corrosion or damage, and replace worn parts before use. For recovery operations, attach only to designated recovery points or rated towing eyes and avoid non‑rated body panels or weak points.
If you are unsure about the correct size for your vehicle, seek professional help from a mechanic or the vehicle’s dealership to avoid injury or damage.
Summary
The thread size for towing eyes varies by vehicle and region, with common modern sizes including metric M12/M14/M16 (and sometimes M20) and imperial sizes like 1/2"-13 UNC or 5/8"-18 UNC. Always verify with the vehicle’s manual or OEM tow eye kit, measure accurately, and only use parts that meet the specified load rating and pitch. Safety and compatibility are paramount when performing any towing or recovery operation.
