AMSOIL Black Oil Filter
Product codes and package options
| Product code | Package or selection |
|---|---|
| EAOM | Filter family; select a vehicle-specific part number |
Run the vehicle lookup before you order a black canister. AMSOIL Black Oil Filter is a four-part spin-on powersports family, and only EAOM103 and EAOM109 carry ATV and UTV applications. All four use advanced full-synthetic media rated 99% efficient at 20 microns under ISO 4548-12, a nitrile sealing gasket, and an 11 to 17 psi bypass relief valve. Thread pitch, height, application list, and anti-drainback-valve fitment change by part number, so the black finish tells you nothing useful about the match.
Two numbers reach ATVs
EAOM103 carries the broadest list: various power equipment, lawn tractors, ATVs and UTVs, marine engines, motorcycles, and snowmobiles from Arctic Cat, Honda, Kawasaki, Komatsu, Kubota, Mercury, Polaris, Yamaha, and Yanmar. That range comes from shared filter requirements, not from a claim that every machine in those brands takes the same part.
EAOM109 narrows the field to various ATVs and UTVs, motorcycles, and snowmobiles from Arctic Cat, Aprilia, Suzuki, and Yamaha. Those two numbers hold the black line's ATV and UTV coverage. EAOM134 and EAOM135 work elsewhere, so do not let the family name make the choice.
EAOM134 and EAOM135 work somewhere else entirely, covering power equipment, lawn tractors, and motorcycles from BMW, Buell, Harley-Davidson, Indian, and Moto Guzzi, with BMW appearing on the EAOM134 listing only. Neither one reaches a quad or a side-by-side. An application list of this kind names supported families, so finding your brand on it does not confirm a fit for your model and year.
The pitch you cannot see
Set EAOM103 and EAOM109 on the bench and they look nearly identical. Both are black spin-on filters with the same 2.47/2.2 in. gasket. EAOM103 is 2.54 in. tall and 2.68 in. wide with an M20X1.5 thread, while EAOM109 is 2.47 in. tall and 2.67 in. wide with an M20X1.0 thread.
The difference is seven hundredths of an inch and thread pitch. Both threads are 20 mm across, but the spacing between crests changes. Do not sort that out by eye or by forcing a filter on the mount. Let the lookup return the part number and install that number.
Read the 20-micron rating
Particle-filtering efficiency is 99% at 20 microns under ISO 4548-12. A micron is one thousandth of a millimeter, so these are particles you will not see in drained oil. The test method matters because it gives the number a defined way to be compared.
That rating is one point on the filter curve. It tells you what happens at 20 microns, not at every particle size moving through the oil. Two filters can share a headline number and still behave differently above or below that size.
The media is the same high-performance synthetic construction found in automotive AMSOIL Oil Filters, built to trap and hold a greater amount of small, wear-causing contaminants than conventional media and other high-efficiency filters. The design targets longer life, smaller particles, and less restriction than other filters while keeping oil flowing continuously.
Two valves doing two different jobs
Every black part number carries a bypass relief valve rated at 11 to 17 psi. Pressure across the element climbs as the media loads with debris, and thick cold oil pushes it up before the engine reaches operating temperature. Hit that band and the valve opens, routing oil around the media instead of through it.
That is a deliberate trade. Unfiltered oil reaching a bearing beats filtered oil that never gets there, so the valve protects flow at the cost of filtration for as long as it stays open. It also means a filter left in service too long can spend real time in bypass without anything on the machine saying a word about it.
The anti-drainback valve solves an unrelated problem. Made of silicone, it holds oil inside the filter after shutdown so the next start does not begin with an empty housing, and it stays flexible across the temperature range a machine actually sees. EAOM103, EAOM109, and EAOM134 are listed with one. EAOM135 is listed without, which is one more reason the matched number matters more than the family name.
Wrench sizes, change timing, and warranty limits
The housings are fluted so a cap wrench has something to bite. A 65-67 mm wrench, GA255, fits EAOM103 and EAOM109, and a 76 mm wrench, GA251, fits EAOM134 and EAOM135, both on a 3/8 in. square drive that gets them onto a filter tucked behind a frame tube. Sealing is handled by a nitrile gasket that resists chemical breakdown, which supports durability and long filter life.
A fresh filter goes on at every oil change, on whatever drain interval the vehicle manufacturer publishes for your machine. Neither the synthetic media nor the 99% efficiency result stretches that schedule, and no filter-specific mileage or hour rating is published that could replace it. An element that has worked through a full drain has already collected whatever the oil carried to it.
Two conditions attach to the filter warranty, and both concern use rather than build. The filter has to be properly installed, and it has to come out no later than the service life recommended in writing by AMSOIL INC. or by the engine or equipment manufacturer. Racing, any manned aircraft or aviation application, improper installation, abuse or damage, and use in mechanically deficient equipment all sit outside coverage regardless of part number.
Verified specifications
| Filter media | Full synthetic |
|---|---|
| Nominal efficiency | 99% at 20 microns under ISO 4548-12 |
| Selection | Use the official vehicle lookup for the correct part number |
Questions about AMSOIL Black Oil Filter
EAOM103 and EAOM109 are the two black part numbers whose application lists reach ATVs and UTVs. EAOM134 and EAOM135 cover power equipment, lawn tractors, and motorcycles instead. Use the official vehicle lookup for your make, model, year, and engine.
Thread pitch and a small height difference. EAOM103 uses an M20X1.5 thread and stands 2.54 in. tall, while EAOM109 uses an M20X1.0 thread and stands 2.47 in. tall. Both share a 2.47/2.2 in. gasket, and nothing on the outside shows the pitch.
It is the share of particles larger than 20 microns the media removes under ISO 4548-12, the industry-standard test method. The result describes performance at that one tested size rather than across every particle passing through, so treat it as a single data point rather than a full picture of what the filter does.
Because flow matters more than filtration once the media is restricted. Pressure across the element climbs as it loads with debris, and cold oil raises it further. At 11 to 17 psi the bypass relief valve opens and routes oil past the media, so the engine keeps receiving oil even when the element cannot pass it.
No. EAOM103, EAOM109, and EAOM134 are listed with a silicone anti-drainback valve, and EAOM135 is listed without one. The specification for the matched part number confirms which arrangement applies, since the family name and the finish give no indication either way. All four share the same bypass valve rating and the same nitrile gasket material.
At every oil change, following the vehicle manufacturer drain interval for your machine. No filter-specific mileage or hour figure is published, and neither the full-synthetic media nor the efficiency result lengthens the schedule the manual sets. Heavy dust, deep water, and sustained load move your machine onto whichever shorter schedule its manual defines.
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