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Using a pump to change oil

I bought one of those oil change pumps that you snake a tube down the oil stick tube into the oil pan and pump out the oil. It worked great on my 93 Jeep and my 95 Jeep but when I tried it on my 2006 Chevy it would not go down since the oil check stick was twisted. Do not understand why they twist the oil stick. My 2000 Ford Expedition also has a twisted oil stick.
Is there a way to replace those tubes or am I just screwed and have to use the drain plug?

Would there be a way to put a flexible narrower tube on your sucker, that would seem the easiest.

Unless snaking that pickup tube down the shaft for the dipstick results in the pickup tube being in the lowest point of the oil pan, then this type of oil change is…let’s just say… not complete.

Yes, changing your oil via a pickup tube that you insert in the dipstick tube is far superior to not changing your oil at all, but there is the nagging reality that if the pickup tube doesn’t reach the lowest point in your oil pan, then you are likely leaving anywhere from 1/2 qt to 1 qt of dirty oil–complete with thick sludge–in the pan.
:thinking:

Is it more convenient to pump the oil out rather than drain it? Pumping 4 quarts out of the pan with a hand operated pump through a 5/16 hose sounds like a time consuming chore.

Your dipstick tube is smaller at the bottom inside the pan than at the top. The tube steps down in diameter twice from top to bottom in fact.

https://www.partsgeek.com/95xgq6r-ford-expedition-oil-dipstick-tube.html?utm_source=shopzilla&utm_medium=pf&utm_content=dc&utm_campaign=PartsGeek+ShopZilla&fp=pp&utm_term=Ford+Oil+Dipstick+Tube#immersedview

which may be causing a lot of grief getting the tube in…

Probably to prevent people from using those pumps. They don’t drain the oil to the bottom of the pan. The dipstick tube isn’t designed to allow you to get at the pan’s lower cavities. It’s only aimed to allow the dipstick to go a quart + below the top of the pool, to allow you to know you need to add a quart. And many pans have two levels on the bottom, one higher to clear undercarriage parts and the other lower to collect oil… with the dipstick tube being aimed at the higher level.

The pump pickup tube, on the other hand, takes the oil from about 3/8" above the low surface of the pan. You could easily end up with gump on the pickup screen by virtue of the bottom of the pan never having been drained.

If you’ve been getting away with the pump all these years, it does not mean you’ve been fully draining the oil. It only means you’ve been lucky. I recommend discontinuing this practice.

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Why do you assume it’s a hand-operated pump

OP didn’t specifically say that

It could be something along these lines, for all I know. This one’s pneumatic, and it doesn’t cost an arm and a leg

image

I’m not really a fan, by the way. It could save time, but on the other hand, if you don’t raise the car, you’ll never see anything underneath the car that actually does deserve your attention, such as a torn cv axleshaft boot, or a crusty water pump, for example

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Well you could but then you would also be faced with finding or making a dipstick that would give accurate reading. It also might not work because of other things in the way. You might consider one of those oil drain valves to replace the plug.

Here’s the reason for different shapes of dip sicks.

https://www.quora.com/Why-do-vehicle-oil-dipsticks-come-in-different-sizes-and-designs-I-e-some-are-completely-straight-twisted-curled-etc

Tester

That’s the first time I’ve ever seen one of those @db4690. But when you consider setting that thing up and then cleaning up afterward it doesn’t seem to be much of a time save. And like you there’s a lot to look over under there while the oil runs out. There’s at least 2 fittings to grease on everything I service.

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Seems like it would be easier to just use the drain plug, unless you have limited mobility or something.

…or if you want to save time–albeit with the probability of leaving dirty oil in the bottom of the oil pan.
The Citgo station at which I worked many decades ago began pushing these quickie through-the dipstick-tube oil changes to people in a hurry. I refused to try to sell that service because of its limitations, but a surprising number of customers did agree to having it done simply because it got them out of the service bay in a few minutes.

Even if you and I don’t believe in saving time at the expense of an engine’s longevity, there are people who will “buy” various automotive services simply because they are quicker.

For anyone wishing to get the most trouble free long term service from their car I strongly recommend paying a real professional to take care of maintenance. If properly done a great many minor problems can be dealt with to prevent future catastrophes.

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I’m curious, webguy, what is it about using the drain plug that you’re so averse to? With a pair of ramps, a drain pan (I use disposable turkey-roaster pans), a large piece of corrugated cardboard to slide on, and a box-end wrench, draining oil is downright easy. Easier than using a dipstick-tube pump.

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Those pump kits don’t seem worth it to me. Rather than put stress on my dip stick tube or take a chance that I’ll strip my drain plug with my overzealous tightening, I’d rather just replace my drain plug with a valve.

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Pumping the oil out the dipstick tube would definitely offer some convenience, but if that’s not possible on your vehicle, probably best to just accept the situation and use the normal drain plug method. Maybe someday the manufacturers will offer a port on their engines for that purpose. Even so youd still proably want to drain the oil out using the drain plug every other time or so. That way contaminates sticking low to the oil pan are mostly swept out with the old oil.