What size is a Hilux sump plug?
The typical Hilux oil sump drain plug uses M14 x 1.5 thread with a 14 mm hex head, though variations exist depending on the engine and generation.
Across Toyota Hilux generations, drain plug sizing can vary. This article explains the common sizes you might encounter, how to confirm yours, and what to do if you need to replace it.
Common drain plug sizes found on Hilux models
What follows are the sizes most owners will encounter on Hilux models, along with guidance on how to verify your own plug.
- M14 x 1.5 thread with a 14 mm hex head (14 mm socket) — this is the standard for most modern Hilux diesel engines and many petrol variants.
- Occasionally, in older or certain market-specific Hilux variants, a smaller M12 x 1.25 thread with a 12 mm hex head may be encountered.
Because drain plug sizes vary by engine and market, always verify against your vehicle's manual or measure the plug directly to avoid cross-threading or damage.
How to confirm your Hilux sump plug size
Use these steps to confirm the correct size before you purchase a replacement.
- Consult the owner’s or service manual for the exact drain plug specification, including thread size and head size.
- If the manual isn't available, remove the plug carefully and measure the thread diameter and pitch with calipers or a ruler, noting whether the thread is M14, M12, or another size.
- Check the plug for markings (for example, M14 or M12) that indicate the thread size, and compare the head size with standard sockets (a 14 mm socket fits most common Hilux plugs).
- Choose a replacement that matches the measured size (most will be M14 x 1.5 with a 14 mm head, but some engines may use M12 x 1.25).
- Reinstall with the correct seal (usually a copper washer) and use the torque specification from your manual; torque can vary by engine and model year.
By confirming the size before replacing the sump plug, you reduce the risk of damage and oil leaks. If in doubt, consult a Toyota service centre or a trusted mechanic.
Tips for maintenance and replacement
To keep leaks and contamination at bay, use the recommended washer and sealant (if specified), check for thread damage, and avoid over-tightening. Always reset the oil level to the proper specification after an oil change and dispose of used oil responsibly.
Summary
In most Toyota Hilux models, the sump drain plug is M14 x 1.5 with a 14 mm hex head, but there are exceptions depending on engine type and generation. Always verify against the owner's manual or by measuring the plug, and use the correct washer and torque when replacing it. If you’re unsure, seek guidance from a Toyota dealer or qualified mechanic to ensure a proper seal and reliable oil changes.
What size is the sump plug on a Hilux?
12mm-1.25
Kelpro Sump Plug & Washer 12mm-1.25 for Toyota Hilux LN172 3.0L 5L Diesel 4WD.
What size is the Toyota sump plug washer?
12mm ID X 21mm OD X 1.8mm.
How do I know what size sump plug I need?
Measure Diameter
Measure the width of the plug at the widest part of the threads. If your plug measures 12mm you will need to start looking at plugs in the size range of “M12 x 1.25 to M12 x 1.75″. The “M12” refers to the diameter you measure from the widest part of the threads on your OEM sump plug.
What size thread is a Toyota drain plug?
M12-1.25" Thread Size.
