Isn't gravity draining obsolete?

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Why don't manufacturers put a convenient underhood oil change suction port with a quick disconnect? Dealers and oil change shops would have oil evac pumps and would not have to deal with drain plug threads, oil loss due to not tightening them, etc.

It works on boats.
 
Ya, that sort of thing is necessary for boats, given that the motors are usually in very tight quarters. Such a port just doesn't seem necessary for automotive applications, and as Anies mentioned, requires buying new equipment.
 
Sounds like it would almost make sense if it were made such that you had the option to suck it out quickly or let it slowly drain. It would be a competitive advantage in that the quick change oil guys could get you in and out faster, but they have to try to upsell you on other things, so that takes time anyway, a qucik drain may not speed things up. And it might cost an extra dollar or two for car manufacturers and what benefit would they get in return? The car making business changes very slowly and the transition from Carburetors to fuel injection took too long as did disc brakes, single key for doors and trunk, electric steering assist etc.
 
It would be nice if someone would come up with a small battery operated vac device with a little hose that you could stick in the drain hole and get out every bit of old oil out of there. Kind of like the dentist uses. I've rigged up a turkey baster type suction thing that I use but battery powered would be so much better. I probably get another half cup of oil using this. Not much, but peace of mind is worth a lot :)
 
Topside oil extractors are quite convenient and not terribly expensive (a good one runs about $70). It's only "more" equipment if you already own jack stands or ramps; if you don't, then you're starting out with something safer, easier and cleaner.

Opinions I've read on them is that you get more oil out than by the gravity method, though I've never seen hard numbers on this.

I don't think gravity draining is obsolete, but I do prefer using an extractor.
 
I am perfectly happy with the current oil change setup. I rather they install an oil reservoir to prevent dry/cold start wear but I know they won't because that would mean engines will last twice as long.
 
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I just went and did some reading on oil extractors. I would definitely do this except for one thing......... the filter! I like to change my filters frequently, usually every OCI. If I still need to crawl underneath and deal with the filter I think there is little benefit to the extractor.

But if/when we move to cartridge type filters, the extractor would be a no-brain'er.
 
Originally Posted By: ledslinger
Why don't manufacturers put a convenient underhood oil change suction port with a quick disconnect? Dealers and oil change shops would have oil evac pumps and would not have to deal with drain plug threads, oil loss due to not tightening them, etc.

It works on boats.


Because suction draining... well.... sucks. You never get the very bottom 1/2 inch of fluid out of the sump that way. Gravity draining empties right down to the very bottom.

You HAVE to live with poor oil draining on boats, you don't have to in cars and industrial engines.
 
Originally Posted By: Kyk noord en
Topside oil extractors are quite convenient and not terribly expensive (a good one runs about $70). It's only "more" equipment if you already own jack stands or ramps; if you don't, then you're starting out with something safer, easier and cleaner.

Opinions I've read on them is that you get more oil out than by the gravity method, though I've never seen hard numbers on this.

I don't think gravity draining is obsolete, but I do prefer using an extractor.


+1. I've read where some people have attempted to 'prove' that they don't get everything only to see little or no oil come out of the sump when they pop the drain.
 
I like to get under the vehicle every OCI anyway, and inspect seals, CV boots, exhaust bolts, etc. I could use an oil extractor, but don't see the point. I'm under the vehicle anyway.

The only time I could see an oil extractor getting more oil out than gravity drain is if putting the vehicle on ramps moves oil away from the drain hole (like if it's at the front of a flat pan, or behind a baffle, etc).
 
I still have to get under the vehicle to get the filter out, so pulling a drain plug is no biggie for me. Now if I had topside access to the oil filter it might be worth it for me.
 
Originally Posted By: 440Magnum
Because suction draining... well.... sucks. You never get the very bottom 1/2 inch of fluid out of the sump that way. Gravity draining empties right down to the very bottom.

This depends on the engine design. It can go either way.
 
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Originally Posted By: 440Magnum
Originally Posted By: ledslinger
Why don't manufacturers put a convenient underhood oil change suction port with a quick disconnect? Dealers and oil change shops would have oil evac pumps and would not have to deal with drain plug threads, oil loss due to not tightening them, etc.

It works on boats.


Because suction draining... well.... sucks. You never get the very bottom 1/2 inch of fluid out of the sump that way. Gravity draining empties right down to the very bottom.

You HAVE to live with poor oil draining on boats, you don't have to in cars and industrial engines.


My experience with these is quite a bit different, and this is totally untrue for many. On my previous BMW 330ci, you could drain it out of the drain bolt until it was "dry" then drop the topsider in and get out another 1/2 liter. The fact is, the threads on the drain bolt are often a little higher than the bottom of the oil pan, which gets hoovered dry like a kid with a straw using an oil extractor. On my Chev avalanche, with the 5.3L v8, when you opened the drain plug after extracting the oil with a topsider, nothing would come out.

Many german cars are designed this way, and are serviced at the dealership with topsiders. I have also read that Mercedes actually had a fitting as mentioned by the OP for service department oil extractors.

The biggest trouble with them is that many engines have a baffle or something inside the engine (like my wife's Odyssey) that doesn't let the extractor tube make it to the bottom of the sump. Otherwise I'm a convert. If the engine architecture allows it, I don't know why you wouldn't use one.
 
Originally Posted By: Jim 5

The biggest trouble with them is that many engines have a baffle or something inside the engine (like my wife's Odyssey) that doesn't let the extractor tube make it to the bottom of the sump. Otherwise I'm a convert. If the engine architecture allows it, I don't know why you wouldn't use one.


That wouldn't be a problem if, like the OP suggested, the manufacturer put in a specific suction port.

I love the Fumoto I put on my Tacoma. I'd use one on the Corolla too, but it sits lower and I'm afraid it would get hit with something the wife ran over.
 
Originally Posted By: crw
OK,... now we need a list of engines that are greatly benefited by use of an extractor.


The nicest thing about the BMW inline six is the cartridge filter accessible from the front/top of the engine. Just suck the oil out with the topsider, open the filter housing cap, lift the filter out and drop in the the bottom half of a cut 2L coke bottle, drop new filter in,close housing, fill sump, done. No need to change clothes or get dirty. Easiest oil change ever!
 
I think it depends on the car. On my current car, my initial reaction is "why on earth would I need that?". I get almost all of the oil out with a gravity drain (with the car parked on a very slight slope), and I can access the drain plug easily without lifting car. It has a rubber washer molded into the drain plug and hasn't leaked a drop from there since I've had it.

Thinking back though, most of my other cars had either poor access, required removing stuff to drain the oil, oil coolers which didn't drain, or leaky drain plugs. So yeah, I can see the utility in it.

That said, after servicing my (3) differentials, I really would have preferred not to have to vacuum out all of the fluids...
 
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Originally Posted By: 440Magnum
Because suction draining... well.... sucks. You never get the very bottom 1/2 inch of fluid out of the sump that way. Gravity draining empties right down to the very bottom.


Exactly. IMO there's no substitute for being able to drain from the very bottom, where all the nasties settle.
 
Originally Posted By: M1Accord
I am perfectly happy with the current oil change setup. I rather they install an oil reservoir to prevent dry/cold start wear but I know they won't because that would mean engines will last twice as long.


Uhh no, the reason they won't is because it's completely unnecessary. When engines are already lasting 300k miles, and are usually the LAST thing on a vehicle to break (most vehicles are NOT sent to the junkyard because of engine problems), why the heck would an automaker waste time, reources, and money putting an oil reservoir on their vehicles??
 
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