Oil filter sockets come in a range of sizes and styles, so you’ll have to determine which size filter your engine uses first. And don’t be surprised if you start accumulating new ones for every vehicle you own. (Image/OnAllCylinders – Paul Sakalas)

Mechanics like to joke about their disdain for vehicle engineers, particularly those that put regular service items in hard-to-reach locations—making routine vehicle maintenance a real pain.

And perhaps nowhere is this disdain more acute than with oil filter placement.

On certain vehicles, simply changing the oil filter often requires you to pull back aero panels, turn the wheels, drain the wiper fluid, drop the gas tank, remove the axles, tune the radio, roll down the windows, recite an incantation, clap really loud…you get the idea.

That also means these oil filters are often found in very, very tight spots, which makes it impossible to get a standard oil filter wrench in there.

So…how do ya get the dang filter off?

Enter our friend, the oil filter socket.

And that’s exactly what it is: A big honkin’ socket that goes around the top of the oil filter so you can twist it off like you would a standard nut. The socket typically has a regular 3/8-inch drive female coupling on top, then you simply insert your ratchet and get to work.

An oil filter socket sits on top of the oil filter canister, giving you a solid, secure way to spin the filter on and off. (Image/OnAllCylinders – Paul Sakalas)

How an Oil Filter Socket Makes Your Life Easier

For starters, an oil filter socket won’t pinch and crumple the relatively thin sides of the oil filter canister like a wrench will, mitigating the risk of damaging the filter to the point that it cannot be easily removed. Better yet, it won’t slip like a strap wrench could—you get a nice, secure grip on the head of the oil filter. (That makes oil filter sockets quite handy when you’re dealing with an over-tightened oil filter, too.)

And as alluded to earlier, it’s downright essential in tight places, particularly those oil filters nestled in between, behind, or underneath exhaust components.

Here’s the oil filter location on a late model Subaru Boxer engine. It’s snug inside the donut hole of an exhaust manifold. A tight fit for sure, but don’t forget, those heat shields can get really, really, really hot too. An oil filter socket saves the day—and your wrist. (Image/OnAllCylinders – Paul Sakalas)

Speaking of exhaust components, if you’ve got a motorcycle with an inline engine, there’s a good chance the oil filter is tucked right behind the engine’s header tubes. Again, an oil filter socket is downright essential here.

You’re supposed to change the oil while the engine is warm, but snaking your hand between blazing-hot header tubes is a bad idea. Oil filter socket to the rescue! (Image/OnAllCylidners – Paul Sakalas)

Finally, a lot of modern front-wheel drive cars with transverse-mounted engines have the oil filter on the side of the motor, which means it might be squeezed between the inner fender and the axle half-shafts (one way) or the alternator or A/C compressor (the other way). While putting an oil filter wrench on here may be do-able, you could save a ton of headaches with an oil filter socket.

The oil filter on this four-cylinder FWD car is squished between the inner fender, front wheel, and CV axle. Using an ordinary oil filter wrench would mean 1/10th of a turn at a time. This oil filter socket makes it a far quicker job. (Image/OnAllCylinders – Paul Sakalas)

A Warning When Tightening an Oil Filter with a Socket

While an oil filter socket makes it easier to spin an oil filter off, be extra, extra careful when using it to spin the new filter on. Regardless of the tools they use, gearheads have a tendency to over-tighten oil filters, making them really difficult to get off 3,000 miles later. And this tendency can be exacerbated when using something like an oil filter socket.

While all engines differ, a good role of thumb is get the filter hand tight, follow up with a quarter turn of the wrench, then back it off slightly. Check out the pic below for another handy tip:

ProTip: When working with oil filter sockets, use a stubby ratchet. Its short handle mitigates some of the mechanical lever advantage you’d have with a longer ratchet. This can help prevent you from over-tightening the oil filter—and your drain bolt too. (Image/OnAllCylinders – Paul Sakalas)

Oil Filter Sockets May Not Always Be a Good Choice

As handy as they are, oil filter sockets aren’t the cure for every oil filter, so don’t go throwing your traditional oil filter wrenches in the trash. These adjustable filter wrenches are still plenty useful in a lot of applications, particularly on older engines using large diameter filters or vehicles with roomy engine bays. And oil filter wrenches often accommodate a range of oil filter sizes, unlike sockets which are intended for a specific canister diameter.

If you’ve got enough room to swing a wrench handle around the body of the canister, those regular wrenches can do the job without a lot of fuss.

So consider oil filter sockets somewhat of a specialty tool, for specific instances where it’s impossible to access the filter with a traditional oil filter wrench.

On this engine, there’s plenty of room to get in with a traditional filter wrench. More importantly, the location of the frame and engine mount makes using a socket impossible here. (Image/OnAllCylinders – Paul Sakalas)

Oil Filter Socket Sizes

You probably already know that oil filters come in a ton of different sizes. That means there are plenty of oil filter sockets out there to accommodate them. Some even offer some universal sizing, thanks to a conical shape and knurled inner walls.

Determining the right oil filter socket for your engine isn’t a difficult job. You can measure the outside diameter of the filter canister. Or you may just want to get the precise part number off your filter, then get its exact measurements from the manufacturer online—and you may even be lucky enough to find a forum thread or blog post where someone already tells you what size/shape/model you need for your car, truck, or SUV.

In other words, a quick bit of internet sleuthing can likely answer a lot of oil filter socket size questions.

This oil filter socket set from Lisle contains five sockets, but there are sets that include many more as well. (Image/Summit Racing)

You can buy oil filter sockets a la carte, yet many tool manufacturers offer handy sets with common sizes. (Buying a kit with assorted sizes might be a smart move if you’re in charge of the family motor pool too.)

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So, if you’ve been burning your wrists, crushing your filter canisters, or chanting spells simply to get your oil filter off, you may want to pick up the right oil filter socket for your ride and save yourself a ton of hassle.

Author: Paul Sakalas

Paul is the editor of OnAllCylinders. When he's not writing, you'll probably find him fixing oil leaks in a Jeep CJ-5 or roof leaks in an old Corvette ragtop. Thanks to a penchant for vintage Honda motorcycles, he spends the rest of his time fiddling with carburetors and cleaning chain lube off his left pant leg.