If you read any manual on changing your oil, it’s going to tell you to let that thing drip for 15 to 30 minutes to clear out as much of the old oil as possible. Meanwhile, your average oil change place is advertising that they will have you in and out of there in 15 minutes from start to finish. Which means there’s no way they’re letting it drip the minimum of 15 minutes.
The soil change was so overdue. There is a difference between the service interval and abuse interval of oil. I definitely got into the abuse range on this occasion. I just didn’t have the money for the oil and the filter.
And while you’re taking care of your own oil change. Make sure to check your brake fluid engine coolant and washer fluid and top them off as necessary.
Drippage doesn’t matter because of how much of the old oil sticks around in the engine anyway.
Change it, change filter, zip it back together, drive offYeah if you’re really that concerned about leftover old oil you’d be better off flushing the system by doing a 2nd oil change a few dozen or couple hundred miles later rather than sitting there waiting for it to drip out.
“Sitting there”? You don’t have anything to do for 15 minutes? Even if I was (more) paranoid and didn’t want to leave my vehicle unattended for that time, I could be productive on my phone for 15-30 minutes…
As a reminder, EVs don’t require oil changes. That makes it easy to forget brake fluid which is still very much a thing.
Isn’t there some kind of sensor that would be able to detect even the slightest chamnge in pressure as an early warning?
I guess it depends on the car. My old Leaf definitely doesn’t.
Well, there’s your problem. Leaves make terrible brakes!
I’ve never had anything drip more than 5 or 6 minutes and between my 3 vehicles and racing vehicles I did probably 10 oil changes last year 🤷.
Regular black stone tests have never turned up any sort of issues.
This isn’t something you actually need to worry about.
Despite this being a hot engine it took 15 minutes and was still dripping. I probably need to dump the new oil and replace it to clear out any sludge from this overdue oil change.
I’d say the drips in comparison to the amount poured back in is negatable.
You are going to have trapped oil in flat areas anyway, that will all get mixed back together. The filter should be filtering, and then it doesn’t matter.
Best to change oil after engine is warmed so that the oil flows out easy.
A pan under the pan is smart. My drain plugs are on the side so it shoots everywhere.
I got better, but once I dumped an entire transmission on the driveway. Pan was lined up for the first glug, not the second through last dribble.
I learned a long time ago that I need a pan under my pan. Something always escapes containment and that second pan makes all the difference. Since we have chickens and geese running around we can’t really have them pecking at shiny liquids on the ground.
I’ve seen goats get into used oil before, and they happily drank as much as they could.
Nothing too terrible happened. They just had really bad diarrhea for a few days. After that, they were just fine.
One of the advantages of being a goat is weighing an order of magnitude more than a chicken. This favors them in a dose-makes-the-poison situation.
Yeah, but they got quite a dose. Five goats shared a whole bucket of nasty old oil that had been drained from a tractor. They got way more oil than some chickens would get from pecking at stains on a driveway.
That said, they’re goats. Goats have some magical ability to eat absolutely anything and be just fine. Chickens might not be so resilient. I know when I had chickens, they sometimes seemed to die if you just looked at them funny.
Might be overkill but I started jacking my truck up on the left side because my drain plug is on the right side of the engine block. Started doing it because the last little but always ended up in my skid plate and I would leave a trail in my driveway after every oil change. But I noticed it drips for much longer when the oil pan is tilted towards the plug.
Instructions clear. Jacking off my truck…
Sounds like you have the oil stains to prove it’s a working strategy.
The oil change was so overdue. There is a difference between the service interval and abuse interval of oil.
For others reading about why changing oil is important: Modern engines use oil for lubrication, yes, but the oil system is also designed as the “sewer” where all the dirt and crap get dumped. Because the oil is flowing through the system and something that is changed a regular interval, it makes a convenient single-item maintenance to keep a whole bunch of bad stuff out of the engine. Imagine every time you have to go to the bathroom you had to store it inside your house. You would use up any container that seals first, then you’d be forced to use open containers, and not only the smell but the danger of diseases would be present. You’d keep those containers emptied outside as often as possible! When you don’t change your oil for long periods of time, you’re keeping your raw sewage of your engine right next to the engines kitchen and work space.
In short: The primary reason for changing the oil isn’t that the oil stops lubricating, its that, over time, it carries all the bad stuff suspended in it. The way to keep the engine clean is to change the oil at regular intervals.
The oil does in fact stop lubricating well too. Shear is a thing and the additive packages stop doing their magic over time too.
Still, unless you live in the desert, the body of most cars will rust through long before you spin a bearing and those are the parts that are most affected by lubrication. Unless you completely neglect oil changes of course. I’m on only 420k km and already the 20 year old rocker panels are perforated on my Audi. Engine probably has another 200-300k km in it, but the car will be unsafe to drive long before that.
Oil filters are a thing, eh.
Sure, filters extend the life of oil, but they do that by using a porous filter media. The larger particulates get stuck in the filter media, and the cleaner oil exits the filter…until all the microscopic holes get filled with particulate matter. Once the filter media is clogged, one of two things happens:
- on cheap and horrible filters, oil goes into the filter…and never comes out. The engine runs dry, heat increases, and you spin a crankshaft bearing or blow a head gasket from the heat generated by increased friction. Engine dead.
- on a good filter, the increased oil pressure from the clogged media forces open a bypass valve in the filter so oil (dirty unfiltered oil) goes straight through back into the engine. The concept being “dirty oil is better than no oil at all”. However this means that the filter is now completely bypassed and the engine oil will continue to accumulate dirt and matter eventually clogging fine oil galleries and causing localized engine starvation of oil, spun bearings, increased heat, etc. Eventually, dead engine.
Oil filters aren’t an infinite life extension for oil. They help certainly, but this help is built into the maintenance schedule for changing your oil. Unless specifically noted by your manufacturer don’t assume you can change just the filter and your old oil is fine.
Thanks for the reminder. My snowblower needs an oil change and carb clean badly.
Knowing me, however, I will do emergency maintenance when the first snow hits and I already have other things on my plate…
That’s the only way to do it. Anything else smells like responsibility.
Do you have to do the blinker fluid alongside every oil change?
A lot of people believe that they can conserve their blinker fluid by not using their blinkers, but they’re wrong. It’s actually lack of blinker use that causes the fluid to seize.
Plus, as we all know, it isn’t standard on BMWs, Mercedes, etc. 🤷🏼♂️
My blinker fluid is fine and at this point I’m not going to change it until I figure out why my brake light isn’t working.
If you add a little bit of red dye, you can use blinker fluid in your brake lights in a pinch.
I was told by two different places that trying to change any of the other oils is more likely to cause a problem if there isn’t one to begin with. I wanted them to do a whole kit on the whole car, but it’s not a good idea according to then.
There is some truth to it. Sometimes it’s better to just top up and keep chugging along on older vehicles that haven’t been well maintained.
A lot of the shops use pressurized system to flush and refill coolant, power steering, brakes. That can pop leaks in old hoses/lines, blow seals etc. It’s much safer if you gravity drain and skip the pump they use in almost every shop.
I was told by two different places that trying to change any of the other oils is more likely to cause a problem if there isn’t one to begin with.
There’s likely vehicle model specific variability here though. I had a first gen Honda Civic Hybrid with the first gen CVT. When maintained engine-to-transmission power was glassy smooth. However the CVT fluid would “wear out” and create a sound/feeling described as “judder”. The fix was to change out the CVT fluid more frequently that the book listed maintenance interval. It was annoying effective. A fluid swap would immediately return it to glassy smooth and silent power delivery.
Doing a slightly more frequent CVT change wouldn’t normally bother me but fluid would only last 20k-25k miles before the judder would start to return (slight at first) and the CVT fluid was Honda specific available only from dealerships and it was expensive. It look slightly less than 4 quarts and was about $7/quart when I had the car. I just checked the price today and it costs $16/quart! So that would be a minimum of $64 for a single CVT fluid change on top of regular oil/filter changes.
I’m gonna have to disagree with them. There is no such thing as lifetime oil. Even gear oil should be replaced eventually. Not too often though. Every 5 years is more than enough for diffs and manual transmissions IMO.
When there’s already a problem, it’s too late to change the fluid. One exception: auto trans fluid + filter change can cure a transmission that’s shifting harsh or flaring during shifts, because ATF actuates the clutches and brakes. But it’s still better to do it before you have problems.
Here you can legally dispose of at waste collection sites5 kg oil + oil filter every year for free, so it will be eco. Also when you doing it DIY you will inspect whatever you see suspicious or need to check. That is really saving your money.
Where I am any auto parts store will take it for free, if there’s a limit I haven’t reached it or been made aware of it.
In my rural area there’s no practical limit to how much you can recycle. No one keeps track of anything. So you can recycle it at the local convenience sites where we drop our regular trash. Or you can stop by Walmart and recycle it there and pretty much any local while shop will let you do it too.
After topping off the bug splatter juice. I definitely looked around to make sure everything else was in order. At this point our car that has 220,000 mi on it (it had a new engine put in at about 125,000) only needs three things. To find out why the left brake light doesn’t work (I’m pretty sure it’s a wiring issue because the problem survived two bulbs), replace the two front tires (I’ll be buying used), and finding the right size bolt to secure the hood release lever. Because that bolt seems to have disappeared.
Parts stores in the US (Autozone, Advance, Pep Boys, etc) all accept used auto oil.
5 KG? My crankcase takes 8.8 liters, I couldn’t bring in a single drain for free over there lol
You can also reuse.
Used engine oil shouldn’t be used in engines again, but it’s often still plenty good enough for things like lubricating bicycle gears and wheelbarrow axles, quieting squeaky hinges, and being used as chain oil in a chainsaw. A light coating of it will also help prevent rust on metal parts and tools.
It’s much dirtier and more likely to cause stains than the proper oils used for those purposes … but it works, and you can easily get it for free. Especially good if you change your oil on time and it isn’t too nasty when it comes out of the engine.
You can also reuse.
Used engine oil shouldn’t be used in engines again, but it’s often still plenty good enough for things like lubricating bicycle gears and wheelbarrow axles, quieting squeaky hinges, and being used as chain oil in a chainsaw. A light coating of it will also help prevent rust on metal parts and tools.
I would discourage that. Used engine oil is very carcinogenic and can be absorbed through the skin. New engine oil is fine and doesn’t carry this risk. For the very very slight savings obtained by reusing old oil, I don’t think its not worth the health risk.
Came to say, I’ve taken neighbor’s old oil for chainsaw use. Double use!
Do you change the oil in lawn mowers? I know you’re supposed to, but I don’t. do I really have too?
Most definitely. Rarely in the push mower but the riding mower gets checked at the beginning and end of season.
Shouldn’t that be a matter of the engine type? i remember learning decades ago that 2-stoke engines lubricate through the oil added to the fuel and most lawn mowers are typical 2stoke engines, right?
If you’re mixing oil and fuel like in a 2-Stroke then there is no oil to change. This is found in smaller things like chainsaws and weed eaters. Not in mowers. If there’s a separate oil reservoir that oil needs to be changed out. Because in that case it’s not mixed with the fuel.
I remember that we used to have a 2 stoke mower 30 years ago. Things might have changed. Or its a regional difference. Anyways, at least I was right about the engine type.
How often on the push mowers?
Usually each time it breaks. And the beginning of each season just to make sure it isn’t low.
Officially? No idea.
Cool thanks
At oil change shops I’m pretty sure they use compressed air to blow all the oil and residue out
I can confirm for you that they do not do this.
Source: I worked at one for many years. We let it drain till it was either a slow drip or stopped entirely depending on how busy we were.
TIL. Thanks for the information! Once I saw a guy use a special vacuum set up but I don’t think it’s typical. I almost always change my own oil anyways
TIL as well. I’ve never seen or heard of a vacuum setup for oil changes. Other fluids? Absolutely, but not oil. To be fair, I’ve also been out of the industry for about a decade now so some shops may very well be introducing it, just none that I’ve personally seen yet. Neat either way!
It was the cleanest oil change I’ve ever seen. I can’t even remember where he attached the vacuum to, but it had a tube with threading that fit an oil jug and then attached to a shopvac down the line, and it just sucked the oil out into the old container and then he capped the container and that was that. I was gobsmacked
I need that shit at home…that sounds glorious
When they change your oil at a shop they pull the cap off and they unscrew the plug. They don’t attach anything to your car to speed the process up. And there’s nothing they could do that would speed it up. Air pressure with the plug removed would just cause the air to go out the other end and wouldn’t speed up the oil at all.
I feel like a lot of places nowadays just take off the fill cap and vacuum pump it out.
See the other reply about how the oil system isn’t sealed and has an air release gate
That wouldn’t stop a vacuum pump from working though…
Full disclosure, when I was driving an ICE car I did all my own oil changes at home. However, 25 years ago I had to pay to have an oil change done.
And there’s nothing they could do that would speed it up.
The process this shop used was to empty the engine oil, put the drain plug in again, and fill the crankcase with new oil, run the car for 5 min with the new oil, drain again, then fill with more new oil.
In my mind, thats a pretty effective way to get the old oil out.
It will definitely help. But commercial places pinching their bottom line aren’t going to “waste” oil like that.
Hmm, on paper this sounds neat but I don’t think that’s how it works. Where the oil lives (the crankcase) isn’t air tight. There’s a breather valve https://en.wikipedia.org/wiki/Crankcase_ventilation_system which lets air and vapors out. While the engine is running, the vapors are directed back into the intake system so any unburned fuel in the vapors has a 2nd chance.
Either way, adding a little bit of pressure isn’t going to make the oil come out that much faster. The reason why you might want to wait 15+ minutes is because if the car has just been running, oil is all over the place in all the nooks and crannies. Gravity is the only thing that can bring it all back down to the oil pan.
I do use compressed air when changing oil, but it’s to run a vacuum extractor. Vacuum extractors make for a nice clean job, but they are much slower than pulling the drain plug.
They absolutely do not do this and I have no idea why anyone would think they do. It would be utterly ineffective because the oil fill tube goes directly to the sump.
Good lord, the silly things I’m reading in this thread…
