Empirical Proof: Suck Superior to Drain for Oil Change

Ok, finally, some proof that oil change via suction is superior to the "drain" method.

Been wanting to do this for a while: Car is a 2003 E46 330i 6MT with approximately 59K miles. I drove the car into the garage after a long run, and let it cool for 45 minutes. I jacked it up on the jacking points, ensuring the car was level.

I proceeded to evacuate the oil via my usual Mitivac method out of the dipstick. It took about the usual 30 minutes or so, with occasional pumping, to get the oil up and out of the crankcase via the dipstick. I then wriggled under the car and removed the 17mm bolt at the bottom of the crankcase.

You know how much oil came out?

None. Not a drip. Nada. Zilch.

I mean, nothing; the end of the plug was barely wet.

For me, this seals the debate about suck vs. drain; if the Mityvac had left any oil in the crankcase, it would have drained out into the catch tank I had setup.

Case closed.

Or at least a data point of one. Mityvac FTW.

But, really, do a few drops left over really matter?

Awesome Wingspan. I was going to do this test at the next change.

I love the MityVac! It really sucks!

Originally Posted by KrisL

Awesome Wingspan. I was going to do this test at the next change.

I love the MityVac! It really sucks!

Werd, that is pretty cool I sold my MityVac since I now have to get under my car to swap the oil filter anyway...

Nice info, I just can't use this method.

dj

Originally Posted by wingspan

It took about the usual 30 minutes or so

This is a deal killer for me. I can do a whole oil change in less time than that. Until I get older, I think I can manage getting under the car.

Glad to hear! I just recently decided to go that route as well on my next oil change. No more going under the car!

Originally Posted by smolck

I can do a whole oil change in less time than that.

Me, too, but not by crawling under the car. My Pela Pro 14 extractor takes just a few minutes to drain the oil. Maybe the larger capacity (14 liters) helps keep vacuum pressure up as the canister fills.

Originally Posted by wingspan

Ok, finally, some proof that oil change via suction is superior to the "drain" method.

Been wanting to do this for a while: Car is a 2003 E46 330i 6MT with approximately 59K miles. I drove the car into the garage after a long run, and let it cool for 45 minutes. I jacked it up on the jacking points, ensuring the car was level.

I proceeded to evacuate the oil via my usual Mitivac method out of the dipstick. It took about the usual 30 minutes or so, with occasional pumping, to get the oil up and out of the crankcase via the dipstick. I then wriggled under the car and removed the 17mm bolt at the bottom of the crankcase.

You know how much oil came out?

None. Not a drip. Nada. Zilch.

I mean, nothing; the end of the plug was barely wet.

For me, this seals the debate about suck vs. drain; if the Mityvac had left any oil in the crankcase, it would have drained out into the catch tank I had setup.

Case closed.

Or at least a data point of one. Mityvac FTW.

I've been using an oil extraction pump for three years and was easily convinced that oil extraction is a great and easy way to go. I have a Pela PL650 and it only takes a few minutes to extract out the oil from my 2002 330Xi and Lexus RX300.

I also use the pump to suck out the residue oil from the bottom of the oil filter canister and have used it to suck out power steering fluid.

In 30 minutes, the remaining oil in the crankcase will evaporate with the regular method, and you don't have to pump. Who has that much time to drain the oil anyways?

Originally Posted by wingspan

For me, this seals the debate about suck vs. drain; if the Mityvac had left any oil in the crankcase, it would have drained out into the catch tank I had setup.

(And you probably let your car cool down too much if it took 30 minutes to drain the oil. It only takes maybe 10 minutes to extract the oil when I do it - using a Pela 650 - but my car is pretty well warmed up.)

I never timed how long it takes using the Mityvac, but I have noticed that I it takes an extra beer to change the oil now

I <3 my mityvac. It takes about the same amount of time for either method, being that you dont take 20 minutes jacking up the car and playing with jack stands when you use the vac.

Originally Posted by Cliff

(And you probably let your car cool down too much if it took 30 minutes to drain the oil.

Yep, hotter oil goes much faster. I think 20 mins from hood up to hood down for me.

I did similar test with transfer case on my Jeep, exact same results. All fluid was fully extracted.

Out of curiosity, how long does it take to clean up the pump afterward? Do you just wrap up the hoses around the pump and put it away? Do you need to flush the hoses? I'm interested but I would hate to have to clean it up after each time.

I don't jack up the car to do an oil change. I drive it up onto my Rhino ramps so it takes no time at all.

Originally Posted by ckleung100

Out of curiosity, how long does it take to clean up the pump afterward? Do you just wrap up the hoses around the pump and put it away? Do you need to flush the hoses? I'm interested but I would hate to have to clean it up after each time.

I don't jack up the car to do an oil change. I drive it up onto my Rhino ramps so it takes no time at all.

Some oil residue will remain in the hose. I hang mine and allow it to drain out. It's a very minimal amount tho, and hot oil will have less chance of staying in the hose too. I don't flush or clean it out, but I suppose if you wanted to you could squirt some parts cleaner thru it.

I then empty the reservoir into my recycle jug, done. Even that can be done without getting dirty.

Alright wingspan. Thanks for the info. Guess I'm going to use a Mityvac now

BTW, which model # is it?

Is it this one?

http://www.amazon.com/exec/obidos/AS...rformanceix-20

warm the engine up first ........yeah, it takes 20 min to drain it with a few extra pumps when it slows down, I am always putzing around the garage or backyard anyway doing other stuff so it's no big deal. I hang the hoses so they drain down into my oil jug for a day afterwards. Easy and no dumb jackstands or ramps

I have the 7201 you linked to, as well as the optional brake bleeder kit. The bleeder kit is nice if you are doing a brake job by yourself.

Originally Posted by Vitacura

Is it this one?

http://www.amazon.com/exec/obidos/AS...rformanceix-20

I have this one:

http://www.amazon.com/Mityvac-7400-L...8683385&sr=1-3

Originally Posted by jvr826

Some oil residue will remain in the hose. I hang mine and allow it to drain out. It's a very minimal amount tho, and hot oil will have less chance of staying in the hose too. I don't flush or clean it out, but I suppose if you wanted to you could squirt some parts cleaner thru it.

I then empty the reservoir into my recycle jug, done. Even that can be done without getting dirty.

Originally Posted by tmba2002

I never timed how long it takes using the Mityvac, but I have noticed that I it takes an extra beer to change the oil now

True, dat.

I just realized that Wingy put "Suck Superior" in the title....:

That is funny!

Ok, back to adult conversation now, my third grade moment is over.

What about this?

Using an oil extractor will not remove the heavy sediment from the bottom of an oil pan. This can lead to excessive build up. A traditional oil change is always the best method of proper engine maintenance.

from this site:

http://www.carbibles.com

I was so excited to get a sucker and not have to deal with the prospect and mess of getting under the car until my bro sent me that link.