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So I’m getting ready to change my oil, and thinking about putting in a Magnetic oil plug. I went to Google, and typed in “ Magnetic oil plugs, pros and cons”. One point that was mentioned was if you hit a hard bad bump, that there is a possibility of the magnetic clump of particles that are on the plug, to become dislodged as a large clump of magnetized steel now being sucked up into the engine .
Any thoughts??
Does the oil in the pan get sucked up from the pan and then go through the oil filter??

Or does the oil in the pan go to the engine first, then flow down to the oil pan through the filter.
Thanks for all replies
Not Sure:confused:
 

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I find them to be unnecessary. The oil filter is capable of capturing any metallic wear that might cause significant damage, and if your magnetic oil plug does accumulate any amount of metal, you've already had some kind of significant failure.

Outside the break-in period, most people find that they provide no benefit.
 

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I agree with XR. No need for magnetic plug. And the oil goes through the filter first under pressure, get circulated through the engine, returns/drips back into the pan and does the cycle again. In a four quart pan it's an educated guess that at least a quart and a half is "somewhere upstairs" while the rest is in the pan. The smaller the pan the more critical the correct level of oil.
 

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The oil is pumped from the sump (pan) to the oil filter to the oil gallery to bearings to sump. The mag plug was used in non filtered engines such as the Volkswagen flat four. They are not necessary in modern filtered engines. Routine oil changes with filter changes keep the oil and filter fresh.
 

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I'm surprised to see the above posts. I've used magnetic plugs in motorcycles and street and race cars for years, and I do think they provide benefit. The difference won't be huge (unless you just happen to catch an impending catastrophic failure, but that would be rare), but there is a reason many auto trans pans have big magnets in the bottom of them from the factory. I always find tiny particles of iron on my plugs, and a small amount is normal. The filter isn't going to catch everything. To me, it's just inexpensive added insurance. I use a Ti plug with integral magnet, so it's no heavier than stock, but provides the added insurance. The plugs I use are also cross-drilled for safety wire, which is another added bonus.

To me, going without a mag plug in the trans, engine, or diff, is like changing engine oil topside when you can do it from underneath. I just hear a man in a suit that doesn't want to get his hands dirty, saying "yep, good 'nuff for gubmit work." Maybe, but not good enough for my shop.
 

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it has been my experience there is no harm in using a magnetic oil plug. to me it is a bit of insurance. is it necessary, no. but by the same token insurance is not necessary (except by law), as to the ability for a car to function, but if you are involved in an accident, you sure want to have it. the same is true for a magnetic plug, it will give you some indication of an impending failure. I personally use one in all of my cars and like the ability to check for fuzz and chips which may settle in the oil pan. I have never heard of a magnetic oil plug causing any type of a failure, so there is no downside....
 

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I'm surprised to see the above posts. I've used magnetic plugs in motorcycles and street and race cars for years, and I do think they provide benefit. The difference won't be huge (unless you just happen to catch an impending catastrophic failure, but that would be rare), but there is a reason many auto trans pans have big magnets in the bottom of them from the factory. I always find tiny particles of iron on my plugs, and a small amount is normal. The filter isn't going to catch everything. To me, it's just inexpensive added insurance. I use a Ti plug with integral magnet, so it's no heavier than stock, but provides the added insurance. The plugs I use are also cross-drilled for safety wire, which is another added bonus.

To me, going without a mag plug in the trans, engine, or diff, is like changing engine oil topside when you can do it from underneath. I just hear a man in a suit that doesn't want to get his hands dirty, saying "yep, good 'nuff for gubmit work." Maybe, but not good enough for my shop.
We are discussing this in the context of engine oil. There are obvious and valid benefits for transmissions, gearboxes, and differentials, which often have poor or no filtration capabilities. There are potential benefits in racing environments where you are pushing an engine to its absolute limits, and I mean through tuning and modification, not through driving aggressiveness. In those cases, where you expect failure, a magnetic drain plug can provide you an additional level of protection that *can* have benefits for reducing oil pump wear so those particles aren't picked up (although that's what the oil pick up screen is for), but if you're finding a significant amount of metal in your engine oil drain plug, you're probably tearing down the engine to fix whatever's broken anyway.

it has been my experience there is no harm in using a magnetic oil plug. to me it is a bit of insurance. is it necessary, no. but by the same token insurance is not necessary (except by law), as to the ability for a car to function, but if you are involved in an accident, you sure want to have it. the same is true for a magnetic plug, it will give you some indication of an impending failure. I personally use one in all of my cars and like the ability to check for fuzz and chips which may settle in the oil pan. I have never heard of a magnetic oil plug causing any type of a failure, so there is no downside....
If you find any accumulation on an engine oil's magnetic drain plug, you have already experienced a failure of some kind and your vehicle requires service immediately. Modern engines don't wear in the way you seem to think they do. We don't have flat tappet cams that will exhibit continual wear so you'll start seeing more metal as an early sign that something is about to go shortly. If anything, an oil analysis report might pick up some metallic wear from the turbo, but those bearings are non-ferrous, so you wouldn't catch them on a magnetic drain plug anyway.

I think the bigger issue is making decisions for reasons that don't have much technical justification.
 

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if you hit a hard bad bump, that there is a possibility of the magnetic clump of particles that are on the plug, to become dislodged as a large clump of magnetized steel now being sucked up into the engine .
Alfa Twincam and Twinspark engines have used brass plugs with magnets for years-

https://www.alfaholics.com/parts/105-series/engine-parts/sump-plug-with-magnet/

I've never heard of this happening!

One customer found part of the camchain split link attached to his when he did an oil change recently though and it's common to find something stuck onto the magnet that some chimp of a mechanic has dropped into the engine at some point in the past.

Not sure I'd bother fitting one though in 100,000 miles of my ownership (and at nearly 200,000 miles total) I've never found a thing on the sump plug magnet in my Alfa!
 
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