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Changing oil filter without changing oil?

Maintenance/Repairs
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#1

Is it necessary to drain the oil before replacing the filter? If not, do you lose oil when removing the filter like when pulling the oil drain plug?

Here’s some backstory if anyone is interested…

I tried changing the oil myself on my old 96 Toyota Tacoma (180k miles), which I use as a backup vehicle and drive once a week. I had my oil changed by a mechanic last August using synthetic which is good for 6 mo / 5000 miles and oil filter supposedly good for 1yr / 15k miles. The truck is leaking oil and I decided to change the oil myself using high mileage synthetic oil as well as Lucas Engine Oil Stop Leak

I drained the oil but had difficulty removing the oil filter. It’s difficult to reach and i gave up after several attempts and just left that filter on since it still should be good until next oil change in August, plus it was getting late. I’ve only driven my truck about 800 miles in 6 months since previous oil change in August. I did manage to put a small nickel sized dent on the oil filter trying to remove it. Hope that doesn’t cause any issues.

Now I’ve found a better tool for removing the oil filter and was wondering if I could make another attempt to replace the filter without having to drain the new oil and the stop leak treatment I spent about $30 for. Will I lose oil when removing the oil filter like when pulling the oil drain plug? If oil should be drained first I guess I will just wait until the next oil change in 6 months

#2

Others may not agree but we are talking about an old back up seldom driven vehicle. I would just wait until next oil change. I can see high mileage oil but I really would not use something expensive.

#3

No.

I believe your filter is “upside-down” and oil will drain out of the filter when removed.

I also would wait until your next oil change to do it, though.

#4

I change the oil on My GM cars and Dodge Caravan. I always remove the filter, first, and then drain the oil. The only oil I lose when I remove the filter is the oil that was in the filter. The rest stays in the engine oil pan.

The reason I do it in this order is that while the oil is draining, I’m installing a new filter. It saves me a little time. Also, depending on what you collect oil in, it could be less desirable to have a filter drop into a pan full of oil.
CSA

#5

My 1991 Jeep Cherokee had an “upside-down” oil filter with what would usually be the bottom of the filter in most vehicles pointing at the sky. I would punch a hole in it at least an hour before changing to allow as much oil to drain as possible. At least the filter was very accessible.

#6

Good idea. I would slightly loosen the filter first to make sure I could get it off.

#7

I’ve seen a LOT of guys get themselves into trouble, because occasionally a filter doesn’t want to come off, AND now they’ve got a hole in it, as well

5 Likes
#8

Never had that problem but if I did there was plenty of room for my extra large Channel Lock pliers. I hadn’t thought of the possibility. Good advice.

#9

To answer your questions, yes you can change the filter without draining the oil and yes you will lose some oil, between a cup and a half quart depending on the size of your filter.

However, I do agree with the others and just wait until the next oil change.

#10

Forgive me for the lecture. Stop using Lucas in my view. If you have a leak problem just address that. Next don’t go that long on oil changes. Change at 3000 even with synthetic. A seldom used vehicle is still going to generate junk in the oil. On my car that sat most of the time I would change once a year and usually had ten or twenty miles on it. So change more frequently. Also the synthetic may be leading to the oil seepage so you might want to just go back to standard oil for a vehicle that old.

In answer though, yeah you can just change the filter but will lose some oil. Don’t you get oil draining out when you pull the filter off normally? Usually, the book will say 1/2 quart additional if changing the filter, so that’s close to what it might hold but I’d start with 1/2 pint. I think I’d just leave it alone though and change both a little sooner.

#11

You’ll indeed lose some oil if you just change the filter. But not nearly as much as if you completely drained the crankcase. The oil filter is fairly high up on the engine, compared to the drain plug. Best to do this in the morning so the car has had a chance to sit overnight, allowing oil in the valve area to drain back to the crankcase. Just top it off to the top mark on the dipstick when you are done w/the filter replacement job is all.

Just an aside: Auto Repair Books constantly tell you to tighten and untighten the oil filter just using only your hands, no tools. I have no idea why some auto expert would think that a good idea. B/c it isn’t a good idea. Not at all. Hand and arm strength and hand size vary greatly. Plus the oil filter is very hot if you run the engine to operating temperature first like you are supposed to do when doing an oil/filter change. I always use a band-clamp filter wrench to remove oil filters. When installing a new filter, I tighten by hand until the gasket just makes solid contact. Then I place a mark on the bottom of the filter, and tighten the filter until that mark is on top, 180 degrees past the point the gasket just makes contact. Done.

#12

I run my cars to heat and stir up the oil prior to changing. I remove the filter first and very little oil is lost, basically only what spills from the filter. Then I drain the oil pan and install a new filter while it’s draining.

I can’t use a strap wrench on most of my cars. They require a socket type wrench from below.

My AC filters usually specify 3/4 turns after contact. I mark them with tape and do exactly that with a filter wrench.

I fill with amount of oil specified in the Owner’s Manual and usually add a few ounces more. I have it pre-measured in a 5 qt. jug and just pour.
CSA

#13

sooner or later it has to come off one way or another.