Average car Overfilled 1 qt. anyone ever see this cause a problem?

[rstcso]

I would assume, with the history of mass-produced products we all grew up with, there'd be an "Acceptable Overfill Table".

Then again, perhaps such a table would prompt stupes to grossly overfill?

Dipstick full line: Good
Dipstick full line plus 1qt: Better
Dipstick full line plus 2qt or more: Best

 

[Pablo]

I'm going to think Kshahn hasn't posted a million links to the same thread. Mean guy that he is.

1 qt over is never going to be problem.

 

[rstcso]

I'm going to think Kshahn hasn't posted a million links to the same thread. Mean guy that he is.

1 qt over is never going to be problem.

This isn't a subtle attempt to increase sales by one quart per transaction, is it? Just asking.

 

[Pablo]

This isn't a subtle attempt to increase sales by one quart per transaction, is it? Just asking.

Indeed. Mean guy that I am, 1 gallon over, no problem. (For all Sienna drivers, I'm kidding)

 

[ecotourist]

It's most likely that the spec wasn't originally based on quarts but instead is based on liters and then just converted over for the American version of the owner's manual.

While that could be true it doesn't seem to be. The fill volumes seem pretty "unrounded" in either language.

I suspect that a round number of quarts or liters is of no interest to the engineers developing engines. Put on a reasonable size oil pan, determine the too high and too low amounts adding a factor of safety on both ends, put in a dip stick (off the rack whenever possible), state the required fill amounts (with and without a filter change), and let 'er rip.

 

[gfh77665]

An automotive pal built his '89 5.7...he did the "383 conversion" rather well.
He told me the SBC was known to readily accept a quart over.

That alone makes me think this question (overfilling, OK?) is answered case by case.

Mine was 6 over, due to WalMart, LOL!

 

[ecotourist]

My neighbor took his Audi S6 to a local shop less than a mile away instead of his usual mechanic for a quick oil change before going out of town. After all, how can you screw up an oil change, right? Well, it turns out it's not that hard. They drained fluid from under the car, filled the engine with the prescribed amount of engine oil, and proceeded to destroy the engine. The person who drained the oil did so from the transmission, not oil sump.

I have a similar story with a near miss concerning my Volvo. I took it to a quick change place once (and once only). After changing the oil the oil change guy said my transmission fluid was really dirty and should be changed. It had been changed only a few months before so I asked him why he thought that. He pulled off the cap from the steering rack reservoir and said - this fluid is dirty. The likely source of confusion was that the cap said "automatic transmission fluid only".

I can imagine the outcome if he had drained my (manual) transmission and tried to fill it through the steering rack reservoir. I suspect I would have been sent away with no oil in the transmission - with predictable results.

 

[D60]

While that could be true it doesn't seem to be. The fill volumes seem pretty "unrounded" in either language.

I suspect that a round number of quarts or liters is of no interest to the engineers developing engines. Put on a reasonable size oil pan, determine the too high and too low amounts adding a factor of safety on both ends, put in a dip stick (off the rack whenever possible), state the required fill amounts (with and without a filter change), and let 'er rip.

I agree and I actually think engineers worth their salt should strive for at least 1/2 quart (or liter) increments. There's no reason this can't be accomplished, esp with computer modeling today.

Honestly full quart (or liter) increments shouldn't be difficult in 99% of applications.

Even the Pentastar went from six in the JK to five in the JL. I guess there's an example of StellantisCialis engineers doing something kinda right (although a quart less doesn't thrill me)

 

[Bud_One]

While I've not seen 1/2 or 1 qt overfills cause any real issues on the cars I've been around .
Overfilling by 5 qts in a 2000ish Isuzu Rodeo with the 3.2 V6 will cause it to vibrate the entire vehicle at around 60mph .
So 10qts in a 5 qt sump.. not so good.
5.5/6 qts in a 5qt sump ,not so bad.

 

[MuzzleFlash40]

Those are the times when I feel like they are just messing with us because they know it will drive some people nuts! I really don’t understand why they would not just list it as 6.0 in the manual

I agree, it’s done purpose lol The 3.6 before it got its “upgrade” was listed as 6 quarts then changed it. My OCD could never list it at 5.9!

 

[rstcso]

Here's my buddy "over-the-pond"'s opinion:

 

[Urshurak776]

Both Mazdas in my sig call for 4.8. They get 5. Yet, still not to the full line. Have to add a touch more. Roughly .2 quarts to get it to the full line.

Sons Santa Fe takes 5.2 quarts to get it to the full line.

 

[D60]

Also, for the shops that fill from bulk, are they required to periodically have their pumps/guns checked for calibration? I imagine this varies by state, but if never checked, how do you know it's really dispensing what you asked for?

I understand most states have a Weights & Measures Dept for fuel pumps and even commercial food scales, but do they oversee bulk fill motor oil pumps?

@bdcardinal ever seen this at your dealership?

 

[Carlostrece]

Just a guess here but it could be the design that is not linear. For example imagine a funnel upside down. It is narrower up on top and a small loss is very noticeable on the dipstick and down about the 2/3rd mark, oil is in the wider area and much larger volume and it's hard to tell a small loss on the dipstick.

It could also be capillary action through slim tube where the dipstick is measuring. Basically we are dealing with a very small amounts of oil in a tube.
Not sure! It's another wild guess.
Google capillary action.

Sounds like your engine doesn't burn much oil in general and you are saving about 1/3rd a quart and it's all good so don't worry.

I'm not worried. I'm perplexed.

 

[Jetronic]

So it depends on the vehicle. I had a few Northstar Caddies that did NOT like to be overfilled. In fact that led to a viscious circle of oil consumption due to PCV valve scavenging and other things. Those were typically overfilled, even by dealerships, since it specified 7.5 quarts. Mechanics just put in eight.

These days, I think there is a bit of designed in "wiggle room" in order to allow for fuel dilution of the oil. My Mecedes is constantly short tripped, and the oil level creeps up a bit. But a recent 2243 mile trip brought it right back down to normal.

My brother was a mechanic for years. He told me that people would often bring their cars in complaining of oil consumption issues, when in fact they had experienced the exact issue I mentioned.

I"ve certainly come across engines that consumed less oil as the level dropped some. But very few.

 

[Jetronic]

In general, I wouldn't worry if up to 5% over. Meaning 1/4 quart over if the capacity is 5 quarts.

Anything over 5% I wouldn't risk it. You would think by design, they should allow these kind of numbers like at least 3%.

I jknow some brands that changed the dipstick length (shortened them) so people would run more oil in them. H/K...... that was like half a quart more. Officially the capacity never changed.

 

[Carlostrece]

My neighbor took his Audi S6 to a local shop less than a mile away instead of his usual mechanic for a quick oil change before going out of town. After all, how can you screw up an oil change, right? Well, it turns out it's not that hard. They drained fluid from under the car, filled the engine with the prescribed amount of engine oil, and proceeded to destroy the engine. The person who drained the oil did so from the transmission, not oil sump.

He's now driving an Audi RS7, paid for mostly by the shop's owner and their insurance.

Holy cow! I've never seen a Jiffy Lube screw up that badly. I have however seen JL screw up in a variety of aggregious ways. You're saying a mechanic shop did that?

I did once have my Jeep at a shop where the mechanic (who was not certified I'm sure) drained out my front diff oil. Forgot to refill it. Then destroyed the front diff when he test drove it on highway. He lied to me about it saying my diff was bad (without saying why). I found out years later from one of his former coworkers why my front diff had gone bad.

 

[rstcso]

You're saying a mechanic shop did that?

Yes, and this place has a very good reputation. I'm assuming is wasn't their front-line tech.

His S6 was low miles and in perfect condition. The shop's insurance did what all insurance companies do and low-balled what they were willing to pay. The owner of the shop opened up his checkbook and wrote a rather large check to make up the difference. I won't be taking my vehicle there (under warranty for many years), but how a business treats its customers in the worst circumstances says a lot about them.

I watched as my neighbor's very-slightly-used RS7 arrived by truck. From my home office window, I have a great view of it. It's not very flashy, but it's a beast.

 

[Carlostrece]

Yes, and this place has a very good reputation. I'm assuming is wasn't their front-line tech.

I know 3 shops in my local area that have excellent reputations because their front-line/varsity techs are excellent. However, their JV squad techs/assistants are unsupervised fools. So I can't trust those shops, unless they agree to let only their varsity tech(s) do the work. I have personally known the varity guys for 30+ years.

The 3rd shop has 1 excellent varsity guy and a team of good JV guys. At that shop all the JV guys are all reasonably good and well supervised by the varsity. It's the only shop I fully trust no matter which tech(s) work on my car.

My cousin is an amateur backyard mechanic and fabricator. He's does good work when he has time and cares, but if he feels rushed or doesn't care enough, he'll cut corners. If I'm there and present he is more diligent. I generally just use him for basic maintenance and basic repairs that don't require special tools or a lift. He does have a floor jack and jackstands, which he uses for oil changes. If I hadn't become handicapped, I'd do these things myself.

 

[50yr Street Mech]

I personally think that given that oil expands in heat, the only problem with 1 qt over would be the crankshaft getting some resistance from sloshing thru the extra oil, thus reducing gas mileage a tad. Other than that, I don't see a problem