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Advanced Oil Change Tip for All Gasoline, Diesel, Engines:

This trick/tip/hack, whatever you want to call it, is really simple. When doing an oil change on anything that has a filter, before recycling it cut it open and inspect the filter medium. You can now inspect how many metal shavings are in the filter, and have an idea of the overall health of your engine. You can learn a ton about the health of an engine from an extra 10 minutes. Cutting open oil filters is standard practice on airplanes, heavy machinery, and I believe it should become standard practice for cars as well. I learned this trick from helping out with recreational planes and seeing a bunch of cut up oil filters.

Tools You Will Need To Cut Open Your Oil Filters:

Tin Snips
Oil Filter Cutter Tool (Yes, they make a cool tool made to cut open oil filters safely, easily, and fast)
Bench Mounted Vice (Great to have in a shop anyway, but useful to squeeze out excess oil in filter medium)

Aircraft Mechanics Pride themselves on being thorough and safe.

People’s lives (yours and mines) depend on them doing their job correctly and safely. It also means they need to spot potential catastrophic engine failures before they happen.

How are they able to do that? Do they have some sort of magic ball to see into the future?

No. But they do do something very different than what %95 of Auto Mechanics or DIYers do when they change oil.

When they change the oil on an airplane (this mostly applies to recreational/private planes) they cut open the oil filter and check its contents.

Like a fisherman that cuts open a fish to see what it is eating to change up their bait. This gives you such valuable information.

If you don’t see too much in the oil filter then you’re okay. Nothing to be seen here.

What amount of metal shavings is normal?

No, the plane will get pulled in and the engine will be diagnosed further to see what is going wrong with it.

Don’t get me wrong a small number of metal shavings is normal. Aircraft engine or Subaru Forester, metal shavings will happen over time.

What you’re looking for is a big build up of shavings, anything that would alert you to a potential problem. If you take samples every other oil change, you will be able to tell when suddenly you have a ton more metal shavings than your average amount.

How often should you cut open your oil filter and inspect it for shavings?

As often as you have time to do. It will never hurt your engine to inspect the oil filter. I recommend every other oil change or if you suspect your engine is damaged do it every oil change.

Even if you don’t do it every single oil change, this is an awesome tip if you just bought a used car or to do every second or third oil change.

How do professional mechanics cut open oil filters:

If you want to see how the professionals do it to back up their suspicions (say a customer brings in an engine and it is making a weird noise / has a low oil pressure light on) watch this video:

The guy in the video is inspecting an oil filter on a large Cat tractor. Same principles apply and same tools apply to make this easier.

He is using both an oil filter cutter (links to Amazon to check price) (yes they make a tool for this) and a bench mounted vice (links to Amazon) to squeeze out the extra oil.

If you don’t want to spend the money on a special tool to cut oil filters use tin snips:

Maybe you don’t do that many oil changes, then you can just cut the outside edge of the oil filter.

Use some high quality tin snips like in this video: **Just please be careful the edges get super sharp!**

How do you know what is a normal amount of shavings and what is abnormal?

Basically, this comes with experience. I cued up the video to the part where he shows the filter medium on the filter he is cutting open. This a filter from a failing engine, great for a point of references of what is an abnormal amount of metal shavings to find.

Compare that amount of shavings to what you should or would expect to find from a healthy engine:

See the difference between high-quality oil filters and the cheap brands. Link to a video where he does exactly that here.
Figure out what brand for your vehicle seems the highest quality. Quick tip– be a pro– avoid Fram!
Come up with a cool collection of the different brands and make a YouTube video about it.
Be a step above any other oil change shop in your area. Explain the procedure to customers and if they would like to see a portion of their oil filter (make it seem fun).
You could even include a sample piece of their oil filter in a ziplock bag for them to take home (offer that to them before)
You can apply this same idea to fuel filters, especially on diesel vehicles to see if your intervals are good.

Check Out This Video From ChrisFix Where He Cuts Open A Fuel Filter With 300,000 Miles On It!

Or A Fuel Filter From A Diesel Engine Like This Sprinter:

Should you inspect your oil filter every oil change?

No, you definitely don’t have too. If you’re racing motorcycles, cars, or four wheeling trucks aggressively then yes I would argue you should.

This to me is just one more way to be an awesome automotive technician, and really learn from the safest technicians that exist (Aircraft Mechanics).

It may seem super simple and obvious, but you would be surprised how few mechanics do this on cars.

Most probably have never even heard of it, and from my own searches on youtube on how to videos about “How To Change Your Oil” on YouTube, it hasn’t been mentioned once.

For some safety precautions remember that sparks and gasoline are bad. Try not to use an angle grinder on a filter full of gasoline.

That being said I definitely have, and no fires yet. Just be really really careful. Also always have a fire extinguisher nearby whenever you are working any fuel system components on a car. You’d be surprised how fast a car can go up in flames.

Also don’t be dumb. Use gloves, safety glasses, and hearing protectors (all links to Amazon to check prices).

Read here for my article on the three things you really need to own to be safe doing car repair.

Or just watch my video here (Yes, that goofy guy is me):

But, as always have fun, be safe, and stay smart!

Items used in this post / video (Links to Amazon):

Tin Snips
Oil Filter Cutter Tool (Yes, they make a cool tool made to cut open oil filters safely, easily, and fast)
Bench Mounted Vice (Great to have in a shop anyway, but useful to squeeze out excess oil in filter medium)