The Smart-O® Advantage

Smart-O® is the most advanced oil drain plug on the market and offers a complete solution for changing oil drain pan plugs.

Complete Coverage in 18 Sizes

Our 18 plug sizes cover over 30,000 European, British, American, Japanese and Korean car makes and models, offering one of the most comprehensive drain plug ranges and covers 99 per cent of vehicles on the road today.

The O-Ring Protection

The patented O-Ring on a Smart-O® Plug offers intelligent protection. When exposed to engine oil, the ring expands from 10 – 20 per cent, sealing the oil pan from inside the thread to secure the oil inside the pan.

The O-Ring expands in response to heat and hydrocarbons, filling the air gap, blocking any potential leakage between threads and producing a vibration and impact resistant seal that exceeds any other protection on the market.

A Smart Seal

Smart-O® Plugs exhibit the most powerful sealing performance found in any oil drain plug. The O-Ring seal has been proven to survive the most adverse conditions.

Tests include incorrectly installing our plugs in cars that were then driven across the United States for more than 4,500 kilometres in severe heat or extreme cold, conditions that would cause standard oil pan plugs to fail almost immediately and lead to oil leakage, sudden oil loss, engine damage and the loss of the plug.

Even under these circumstances, the plugs upheld their anti-leak, vibration-resistant features, held firmly in the pan, and kept the oil safely in the oil pan of the vehicle.


The O-Ring is designed to prevent self-loosening even from excessive vibration.

The Smart-O® Plug has been subjected to 9G vibrational forces and maintained a firm seal in the oil pan. The plug also underwent the junkers test.

After being subjected to excessive transverse vibrations, Smart-O® did not loosen completely and could be removed by hand turning.

Junkers test conducted by the Oakland University Fastening & Joining Institute and Spectrum Technologies, Michigan.

Preventing Wear and Tear

Quickly installed oil pan plugs can often be mismatched in size to the oil pan, causing damage to the threads.

Even correctly installed plugs can leave stripped oil pan threads after many years of plug replacements.

The intelligent O-Ring seal avoids this with a design that exerts no pressure on the threads, softly expanding to fill and seal the pan.

An Easy Fit

Oil pan plugs are often mismatched to the pan with improper sizing leading to thread damage. Smart-O® Plugs are designed for the busy auto service professional: each plug is identified with a clear headmarking.

Our plug range of 18 sizes will fit most automobiles on the road today.

To find the right plug for any vehicle, you only need the oil pan’s thread diameter and thread pitch.


Oil pan plugs are often overtorqued, causing wear and damage to the pan. Our Smart-O® Plug features SmarTorq where the O-Ring increases the prevailing torque on the plug itself, reducing the need to overtighten the plug in the pan.

Tests revealed that Smart-O® showed higher prevailing torques during tightening and loosening cycles compared to OEM and aftermarket plugs.

Test carried out by the Fastening and Joining Research Institute of Oakland University.

Reducing Risk and Inventory

With a range of a mere 18 plugs, the Smart-O® design cuts down on the need for excessive storage and reduces the risk of incorrect installation, oil pan thread damage, oil leaks and catastrophic oil loss, or  engine damage from oil leakage.

Smart for the Environment

Engine oil is a major source of water pollution. An oil spill of 3.8 litres can contaminate 3.8 million litres of water.

Used motor oil can contain chromium, lead, petroleum hydrocarbons, aromatic hydrocarbons, or zinc and is highly carcinogenic.

Smart-O® offers a smart preventative measure by keeping the oil in the oil pan and out of the environment. In addition, the Smart-O® Plug is reusable, recyclable, ROHS compliant, and its black coating is free of toxic Cr6.


Smart-O® stands for the highest quality. Our plugs and related components are manufactured in certified facilities to ISO/TS standards to ensure they conform to the strictest automotive standards.

Frequently Asked Smart-O® Questions

In-depth answers to your Smart-O® queries.

General Questions

Questions About Using Smart-O® Plugs

Technical Questions



Please select from the following to determine the right part for your car:

Please select from the following to determine the right part for your motorcycle:

The Smart-O® Plug is designed to be installed like the OEM drain plug and torqued to OEM specs. The washer is changed as it provides a secondary level of defence and to ensure correct torqueing preventing damage to the pan thread.

In most cases, Smart-O® Plugs are expected to be used multiple times; however, in cases where Helicoil inserts are used, the condition of the threads of the oil pan may cut the O-Ring on the way out in as little as a single use.

This is actually when the O-Ring has the most value; a regular plug in a damaged or worn oil pan would have a higher probability of leaking. The technician should always consider the make, model and year of a vehicle in order to determine if a Helicoil is present.

Installing F1 plugs in oil pans that use a Helicoil insert may tear the O-Ring; therefore, it is recommended that Smart-O® not be used if a Helicoil is present.

It is recommended that Smart-O® be tightened with a torque wrench. Regular OEM torque specifications should be used for Smart-O. Due to the function of the O-Ring, during removal, the plug will have more resistance than a regular plug and will require a wrench.

Smart-O® oil drain/sump plugs reduce the possibility of oil leakage, reduce environmental and corporate claims, and increase customer retention through:

Smart-O® can withstand temperatures of up to 400 degrees Celsius, so it’s safe to say that it can work in both transmissions and oil pans of engines.

Yes, Smart-O® will work in class 4 PAO oils. Smart-O® will expand using class 4, synthetics, esters, diesters, polyol esters, mineral, and even PAG, ATF, Hypoid, Flax, and just about anything that is slick.

Yes, Smart-O® will expand and can resist negative material effects from transmission oil and engine oil alike.

In principle, Smart-O® can be used as a transmission or filler plug. But we do not have the data for plug fits which transmission and which vehicle, so we are not able to give accurate recommendations. We only provide data for using Smart-O® Plug-in oil pans of automobiles, light trucks and motorcycles.

No. The green coating on the O-Ring is in place to enable a smoother insertion of the Smart-O® on its first application. The rubbing of the threads against the O-Ring will remove part or all of the green coating, even possibly after just the first use. This is expected. Once the plug has been in the oil pan, there is enough oil to keep it lubricated for the next use.

The O-Ring is manufactured from a patented material which is then itself coated with a patented green coating to allow for a smoother first insertion.

There are instances where after removing the Smart-O® Plug, the O-Ring may look deformed or twisted. This is not an instance where a new plug is needed. The O-Ring will contort into the shape of the threads over time. It may appear flat with grooves that may even look like tears in the surface or maybe even as if it is shaved off. This is normal and once removed from the oil pan, given some time, the O-Ring will resume its original shape. Once the plug is reinstalled, it will continue to expand and take the shape of its new home.

Over time, the threads of the oil pan may cut the O-Ring. This may happen more quickly in vehicles that are older or have somewhat damaged oil pan threads. Plugs with cut O-Rings should be replaced. But even if the O-Ring is torn on the way into the pan, the plug will still function as a regular OEM plug. If you feel you are seeing a pattern of certain vehicles with missing O-Rings, please inform your auto service centre, reseller or distributor who will pass the information onto the manufacturer.

The plug will still work just like a standard drain plug. If you observe the O-Ring is missing at the time of service, replace with a new Smart-O® Plug. Remember: even if the O-Ring is missing, the plug will still function as a regular OEM plug. If you feel you are seeing a pattern of certain vehicles with missing O-Rings, document the make, model, year, engine size, and which Smart-O® Plug was removed from the pan. Please inform your auto service centre, reseller or distributor who will feedback the information all the way back to the maker.

The Smart-O® Plug is designed to be installed exactly like the OEM plug. It should never be left loose or be installed without the washer. The washer is there because it would otherwise damage the oil pan surface to torque the plug alone.

When using Smart-O, the seal is now the O-Ring instead of at the washer. The washer provided with Smart-O® is an added protection, with the first defense being at the O-Ring. The plugs and O-Rings are reusable, reducing waste and adding to the eco-friendly oil change. The washer is changed as it provides a secondary level of defence and to ensure correct torqueing.

We do not advise the use of crush washers which are for one-time use only and produce sharp edges when crushed. These edges could cut the Smart-O® O-Ring in the event of removal of washer and plug. There are risks associated with re-use of washers and the use of crush washers in conjunction with Smart-O® Plug

You would need a caliper to measure the expansion and even then it would be hard to measure. Expansion means that the shape of the O-Ring changes from a tube-like structure to whatever environment it is put into. This is why when you remove a Smart-O® Plug from an oil pan it will look like it has threads in it until you allow it to sit for a while until it regains its original shape.

No. The manufacturer or dealer cannot void a vehicle’s warranty due to installation of an aftermarket part unless it was done improperly or it can be proven that this part fails to perform the function it was intended for or damages another part.

Smart-O® is reusable, but for optimum performance, we recommend changing the plug once a year.

It is recommended and common practice in the industry to change the washer with every oil change. The sealing performance of the plug may be adversely affected if crushed washers are reused. If crushed washers are reused, excessive torque will be needed to tighten the plug risking damage to the pan. Smart-O® recommends changing washers with each oil change.

When a standard drain plug is installed properly and torqued to manufacture’s specs, the oil pan and drain plug vibrate at the same frequency when the vehicle is running. Improper installation can cause the flange and washer to not press up against the pan. This creates an air gap between the drain plug and the oil pan. Crankcase pressure and gravity are contributing factors in a running engine that can lead to the drain plug eventually falling out. Oil could also pass through the threads and out onto the ground leading to the evacuation of oil and catastrophic engine damage. The Smart-O® O-Ring prevents oil from leaking through threads due to the self-expansion material. It also grips into threads, virtually eliminating self-loosening of the plug caused by excessive vibration.

No, because no pressure is exerted during expansion. The O-Ring will remain the softest piece of the system between the oil pan, the drain plug, and the washer.

Smart-O® Plugs are identified by the head marking at the top of each individual plug, for example: F1, R1, R3, etc.. Our range of 18 different plugs cover 99 per cent of vehicles sold in the market. Each plug comes complete with a washer and O-Ring.

The black oxidized coating serves as a more environmentally friendly alternative to regular zinc-plated coatings which often contain the hazardous Cr6 substance. The plug is reusable as long as the O-Ring is intact, requiring less replacements. Smart-O® also reduces the risk of oil leakage into the environment.

Incorporated in the Smart-O® Plug is a special O-Ring that is designed to expand up to 10 – 20 per cent when contact is made with heat and/or oil (hydrocarbons). Once this expansion takes place, the O-Ring takes up the air gap and the leak path between the threads of the oil pan and the plug itself. This produces a positive connection between the drain plug/sump plug and the oil pan, allowing the oil pan and plug to vibrate at the same frequency, essentially keeping oil in the pan.

Smart-O® is an oil drain/sump plug, designed and engineered by master auto technicians and special parts manufacturers to help prevent oil drain/sump plug failures, oil leaks, oil pan damage and engine damage due to improper installation of the plug.