Overfilled oil: How bad is it?

I took my wife's daily driver SAAB 9-3 to a chain oil place that is named after someone's sketchy relative.

I try to watch them fairly carefully, but it is hard to always see what they are doing from the driver's seat. I always go (a mile) home and pop the hood and make sure everything is indeed in place and re-check the oil level. It looks like they put too much oil in. The SAAB has a dipstick that is essentially a braided steel cable with a weight thingy on the end. Other GM products from the era might be the same way, not sure. Anyway, the thingy on the end has a prominent notched section in the middle labeled MIN at the bottom and MAX on the top. it looked like there was enough oil in it that the entire weight was covered as well as an inch or two up the cable. WTF?

I go straight back and tell them it is overfilled. I also note that the work order stated they put 7 quarts in. I looked it up and the manual specifies 6.3, they apologize and agree they overfilled it. They drain a bit out the bottom and show me the dipstick. I thought the top of the weight looked clean this time.

I feel better and immediately go on a 40-50 mile round trip. I get back and check the oil level again and I'll be damned if it doesn't still look over-full. So, I have the wife take it back this morning and have them drain some more out. Which they do after apologizing for the inconvenience.

What the berkeley? I am a little bit upset, not screaming mad or anything, just upset. Is this as bad as my mind makes it out to be?

No, it's fine. Engines are tough.

It's hardly worth worrying about. A slight (like .25-.5qt) overfill is commonly done in racing to prevent oil starvation. Even a .7qt overfill won't do any damage from a short bit of low-rev operation.

I usually run a little over in cars that have that 5.5 quart fill requirement. It will not hurt the engine as most of mine went way north of 100,000 miles before the car itself died.

Thanks guys, you make me feel better. I guess I was being a touch OCD about it.

Most of my cars burn or leak a bit of oil. When filling, I toss in .25 to .5 quarts just for future planning.

As a guy who works in one of those oil change places i dont let anything leave overful but my wagon has an extra half quart in it because i run it harder then the factory recomends and it helped smooth out sustained oil pressure hot at high rpm.

Yeah - I overfill my M3 always for track use, and the wet sump Hayabusa in the race car gets way overfilled. Don't sweat it. And if you want an oil change done correctly, DIY.

Extremely overfilled can cause trouble with the crank whipping the oil into a froth. Aerated oil won't pressurize properly. Most vehicles you would likely have to be a couple quarts over for that to happen.

We had an explorer at work that the person did an oil change at home and forgot to drain the oil first. They put 5 quarts on top of the 5 quarts that was still in there. They realized it on their way to work when it started smoking badly. It was frothy, but I drained a bunch out for him and it was fine.

Too much is better than not enough.

curtis73 wrote: Extremely overfilled can cause trouble with the crank whipping the oil into a froth. Aerated oil won't pressurize properly. Most vehicles you would likely have to be a couple quarts over for that to happen. We had an explorer at work that the person did an oil change at home and forgot to drain the oil first. They put 5 quarts on top of the 5 quarts that was still in there. They realized it on their way to work when it started smoking badly. It was frothy, but I drained a bunch out for him and it was fine.

Thats funny. We had a lady come in to work after her husband topped off her oil because the car was smoking. He added a gallon. Honda civic is not happy with 8qts of oil.

A friend at work was just telling me about one of his tenants. She came by the office to pay her rent (he's a landlord) and complained that her car was going to need work and she might be late on the next rent check.

She says the "guys at the shop" told her it was burning/leaking a quart every couple of days (!) and as long as she kept topping it up it would be fine.

He goes out to check and oil is dribbling out the dipstick tube. He jacks it up and drains the best part of a 5 gallon bucket out of the poor car. Apparently it ran much better after that.