(Updated on December 6, 2021)
Nothing ruins a routine oil change quite like finding metal flakes in the drain pan. Metal shavings can often be quite subtle, appearing more like glitter than the large pieces of shrapnel some people may immediately think of.
Is It Normal to Have Metal Shavings in Oil?
Some new engines will show a bit of glitter during or after the break in period. This can be completely normal, and is dependent on both the engine manufacturer and the break-in process for that specific engine.
If your engine is healthy, already broken in, and you are following the recommended maintenance interval for your vehicle, you should never see metal shavings in your oil.
What Does It Mean When You Have Metal Shavings in Oil?
Metal in your oil is typically a sign of an unhealthy engine and never something you want to see. Sometimes it means your oil change intervals are too long. In this case, your engine oil is no longer doing an adequate job of protecting your engine.
If you run the incorrect oil weight or the engine was starved of oil at any point, this may also be the cause of excessive metal particles in the oil.
How Serious is This Problem?
People commonly find metal shavings in their oil under certain circumstances. This does not necessarily mean you need to start shopping for a new engine, but it’s definitely something you should keep an eye on.
Keep a close eye your used oil to see if you get more or less metal shavings over time. If you notice a ticking noise or knocking sound along with the additional wear, start setting some money aside; you may be getting close to needing an engine rebuild.
Will an Oil Filter Catch Metal Shavings?
Oil filters are particularly good at catching fine metal shavings and particles that are even too small to see.
The oil filter’s ability to catch contaminants will diminish over time. Make sure you are changing your oil filter regularly according to the manufacturer’s recommended intervals.
If you notice metal shavings in your oil, it is highly recommended that you at least follow the service interval specified for severe driving conditions. This usually requires you to change your oil every 3,000 miles, even if you’re using a full synthetic oil.
Related: Best Oil Filters for Synthetic Oil
What To Do If you Find Oil Shavings in Your Engine Oil
If you find metal in your oil, all is not lost. Here are some ideas you can try that will help you determine what your next step should be.
1) Compression or Leak Down Test
A compression test and leak down test are both good tests to assess the general health of your engine. An engine must make compression to make power, and a compression test measures how much compression each individual cylinder is generating.
A leak down test helps you figure out where you’re losing compression, and is particularly useful if you’re losing compression in one cylinder and need to figure out why. You can do this test with fairly minimal effort, using only a leak down tester and an air compressor.
2) Used Oil Analysis
A used oil analysis can help you determine the health of your engine over time. If you submit a new oil sample after each oil change, the oil analysis company can track the wear in the engine. For instance, if they see copper levels increase over time, your rod bearings may be wearing more than usual.
If you’re going to send oil in for a used oil analysis, make sure you only collect oil coming out of the vehicle. Drain pans that have been used on other vehicles are very dirty. More than likely, they contain contaminants that will skew the results of your analysis.
Glitter in Your Transmission Fluid
Most transmission and differential drain plugs are magnetic to attract any metal in the gear oil or transmission fluid.
Shiny metallic particles on the drain plug after 30,000 miles or more is fairly common, especially if you’re changing the transmission fluid for the first time. This happens naturally as the gears in the transmission wear in.
If you notice larger chunks or fragments in the gear oil, this is cause for concern. Typically this means the transmission is experiencing excessive wear in the gear teeth. This may lead to problems shifting or putting power to the ground in the future.
If you see metal in your oil, don’t panic. If the particles are very small and everything else about your car seems fine, you can probably continue driving your car without issue.
If you are concerned about the level of metal you’re seeing, it might be worthwhile to bring your vehicle to a shop to have them assess the health of your powertrain.
Take a picture of your oil. If the metal particles are fine, take a video of the oil while you gently swirl it to better show the metal. Finally, consider sending in some of that oil for a used oil analysis.