I’ve been told that pretty much all dealers (and other oil changers) suck the old oil out of the pan instead of draining it. The ability to do this is nothing new, but it was generally thought to an inferior method. I worked in service stations and auto service centers for years in the 60s and 70s, and always raised the vehicle and drained the oil. The proper method was to rum the engine till hot and then drain the oil to the last drop. A lot of ugly stuff would collect in the bottom of the pan if the engine was allowed to cool and the oil to settle.
Anyway, is the “pump out” method standard procedure, and am I overly worried about having a half quart or so of old sediment filled oil mixed with my new oil?
Peace,
mangeorge
I was wondering about this too because whenever I change my oil on my own, it takes a lot longer than 5 minutes to drain all the oil out and there are several “5 Minute Oil Change” places in this area. I always think “I can’t even get the oil out in 5 minutes, how can they do a complete oil change in 5 minutes?”
I can see a few advantages to sucking it out:
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Depending on where the end of the tube resides inside the oil pan, an argument could be made that you actually remove more oil from sucking it out vs. removing the drain plug.
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There is less liability for the shop performing the work, as they can’t be accused of under-torquing, over-torquing, or stripping the drain plug. (This is just an advantage for the shop owner, obviously.)
I remember mention in some Consumer Reports type article years ago that the 5 minute oil change places were doing this kind of thing and it was bad because you end up with a lot of crap in the bottom of your oil pan that never gets drained out. I can’t imagine a dealer or any competent mechanic would ever do this.
Hopefully one of our auto gurus will have an answer for this.
I have to disagree with this. If I was standing in a pit under the car with a big drum to catch the oil, I could remove the drain plug and the oil filter and have the oil drained in about 3 minutes. With a second person up top ready to pour the new oil in as soon as the drainplug and filter are replaced, add another two minutes…especially if they’re using a bulk fill system, which is similar to pumping gas.
Even if you’re doing this in your driveway, you’re only draining about a gallon of oil. The biggest time consumer there is trying to get the filter off from an awkward position where you might not be able to easily reach or see the filter.
Jiffy Lube still drains the oil. I watched them do my spouses car a few weeks ago. I like their setup with the service pit. I also appreciate being able to watch the work as it’s done.
I would never allow the suction method on my vehicle. I agree with the OP there’s too much sediment in the pan that wouldn’t get sucked out.
there’s very rarely any significant sediment in the bottom of the sump. the oil pump pickup only has a large-mesh screen on it to keep any big pieces of junk from getting into the oil pump; anything finer gets sucked up and (hopefully) captured by the oil filter. Motor oil additive packages have components that are designed to try to keep fine particles in suspension for this reason.
pretty much, if there’s any crap at all sitting on the bottom of your oil pan, your engine already need significant work.
When I was workong in the business the plug was always at the lowest point of the pan, called the “sump”. I don’t know about modern cars.
Don’t get me wrong, new cars are far superior to the older ones.
The problem isn’t so much particals as chemicals (acids iirc) and such
but again, the additives in the oil are there to neutralize that stuff and keep it from settling.
I occasionally use a clear plastic container to hold my used oil when I change it on my car and motorcycle. Often the used oil sits for weeks or months until I bring it to be recycled. I’ve never once noticed any sediment, debris, particles, etc. at the bottom of the oil, even after it’s been sitting for an extended period.
I’m not trying to prove a point, I seek knowledge. I suspect those additives, and the oil itself, break down eventually due to heat etc.
Tell you what, I’ll ask at work. I work at the place where they developed Techron. There’s also the lab where they test and develope motor oil additives.
If I remember. 
Interesting. How about on top?
In over 40 years around the auto business I have never seen an oil change done via the suck method.
First off it would take more time not less.
Look at the dipstick on your car and the tube it fits in. The tube on my car might be 12mm inside diameter. Sliding a tube in there with a 2mm wall thickness gives you a 7-8mm pipe to pump out 4-8 quarts of oil. You are going to be there awhile.
Or you can raise up the (Which you may have to do anyway to get the filter and check the brakes and such) and pull the plug which gives you a 19mm hole and gravity does the work.
Then we can discuss cars that have two sumps with two drain plugs, can’t get them both with the suck tube.
The only place I have heard of oil being sucked out is in marine applications where there is no place to drain the oil.
I’m with Rick. I’ve never seen this done when I have had my oil changed.
I have heard of this method for some automatic transmissions though.
Also if it’s taking five minutes to drain your oil you’re either doing it wrong or the oil is way beyond it’s expiration date and has turned into some sort of tar like substance.
I have worked at a Nissan, Honda, Lexus, Jaguar and currently work at a Toyota dealership and have never needed to change the oil via the “suck method”. I have a tool that I use for bleeding brakes that uses venturi vacuum and the shop air to create a vacuum in a small tank. With a hose I could use it to suck the oil out through the dipstick tube but I think it would take a good 10 min since the tube I would need to use would have to be very thin.
Even if the oil in the engine is cold and with an engine with a large oil capacity (Lexus LS460 uses 9 quarts) it wont take more than 3 or 4 minutes to drain.
I have done the reverse though. On the older Toyota minivans the engine is under the drivers seat and normally I would have to flip the seat back and take the engine cover off to add the oil. Instead after the oil is drained I use the shop oil to pump oil up through the drain plug hole. I add about half a quart extra so I have time to put the drain plug back in while a little of the extra oil drains back out.
My observation when removing engine and transmission oil pans is that there is typically a very thin film of “dust,” so to speak, on the pan surface. It requires more than the flow of oil over the surface to remove this, either wiping with a rag or spraying with pressurized solvent (e.g. brake cleaner or carb cleaner). Oil drained into a clean drain pan shows no discrete debris, but may leave somewhat of a similar film.
I do suck automatic transmission fluid out before dropping the pan because it’s easier, even if the pan has a drain plug, and it’s MUCH less messy when there is no plug. I’m less inclined to do it for engine oil because the dipstick tube is narrower, requiring a skinnier suction tube that makes it a rather slow process. With engine oil, there’s also the fact that the pan is not being removed, and thus the possibility of leaving a few ounces in the pan.
I’ve never heard of dealerships or general repair shops sucking rather than draining. I don’t recall the topic ever coming up among my colleagues. I guess some could be doing it and I wouldn’t know, but I’d be surprised. My belief is that it is not a common practice.
While sucking may not get as much oil as draining, properly done it would get 95+% of it. Considering that drain plug threads can get distorted after many remove/install cycles, and that even a competent pro can make a mistake, I’d say either method has its own slight advantage, and I’m not sure a compelling argument can be made that one is better than the other.
On preview: yeah, some of what they said!
Wondering how fast an extractor would work, I found an article on Edmunds.com where they claim it cuts oil change time in half. Then you read on and find that it took them 8 minutes to drain the engine with the extractor.
I guess it’s an improvement for a car that sits low to the ground and needs to be jacked up by the average joe who doesn’t have anything other than the factory bottle jack that came with the car and barely knows what he’s doing. But if you can’t get to the filter from the top, you still have to jack the car up, so they really only work for cars with top filters. Some cars also have shields that have to be removed to get to the drain plug, so that can add to the hassle.
But if you have a decent jack and a normal car that has an easily accessed drain plug, you should be able to have the oil drained 5 minutes after parking the car.
They seem to stress that it’s better because you don’t have to fool with the drain plug. If that’s a worry, just use one of these. I’ve been using one for about 6 years. I attach a short hose which I stick into a jug then flip the valve open. No mess, no dirty hands.
Anyway, no it’s not standard procedure. From my short searching, extractors seem to be marketed to people who want to save money by doing their own oil changes but think it’s too hard or dirty. I even saw one customer quote saying something like “With the extractor, it really is possible to change your own oil!”
I love how on the article for the extractor they use engines with relatively tiny engines. Both the Fit and Elise take 4 quarts of oil (3.7 w/o filter which is what really is in the oil pan). Try doing that on a larger engine with 9 quarts of oil capacity.
BTW I have the same extractor except mine is air powered. NYA 
About 20 years ago I had my oil changed and the guy stripped the oil pan plug. Probably cross threaded it.
I found out the next time my oil had to be changed. Thankfully the guy at the service station was able to replace the plug. The oil pan threads were ok.
Suction would eliminate that happening. But, I still prefer getting it drained the old school way.
A couple of blokes in the workshop at our yard were saying that some new Euro cars (VW, BMW, some Mercs) no longer come with drain plugs on the sumps, and the oil has to be drained by the suction method, discouraging people from attempting to do their own maintenance.