Oil Overfill

[Patman]

I am confident to say that 99% of all engines out there can handle a half quart over the listed capacity and still be totally fine. Manufacturers have to allow some leeway there since they know fast lube places will often round up the amount they put in, and also won't let the old oil drain for very long too.

I bet in most cases it would take a quart to a quart and a half extra before the crankshaft would dip into the oil and cause aeration.

 

[SZR48207]

They overfill because when they underfill customers complain that they got ripped off.

Can't win!

 

[UberArchetype]

I know of at least 1 engine (the muscle-era Chrysler 440) that NEEDED to be overfilled if you wanted it to last very long under strenuous conditions. The design constitutes a situation where the pickup location and sustained hard acceleration (1/4 mile runs) combined to actually allow the pump to run dry. A forward-located pickup and inadequate return flow was a recipe for disaster, as many guys found out the hard way. It wasn't long before people racing them started routinely replacing the pans and pickups with better setups and/or over-filling them.

 

[Tman220]

Originally Posted By: Pelican
Originally Posted By: Spector
Are you saying it is overfilled by looking at the invoice and seeing 6 liters or by looking at the dipstick? Either way though I would not be concerned, a minor amount. If invoice they charged you for 6 but may have only put in 5.7.


Thanks Spector, good point! On the invoice it says 6 litres, on the dipstick I can't tell, even though I looked in the morning after the car rested overnight I could not tell. Glad you confirm my feeling about not being concerned.


So you're telling us you couldn't even confirm an actual overfill on your dipstick? You were solely going off an arbitrary number typed onto the invoice? What a nothing-sandwich!!

Maybe we should start a post that lists all the engines that do or don't tolerate slight overfills. I know a few off hand. I know there are a few corvettes where the manual states that an extra quart of oil is ok when the car is being used on the track. My 2012 regal GS holds takes 6.5 quarts of oil to get to the full line. The 2013 regal GS listed a sump capacity of 5.something quarts and had a longer dipstick, but the manual stated that an extra quart of oil is ok when used on the track. It's highly probable both the 2012 and 2013 regal GS have same oil pan with a quart difference in stated capacity. I would also assume that the 2013 Regal GS would tolerate more overfill (on paper) than my 2012.

 

[Trav]

Originally Posted By: SilverSnake
I never understand these threads on oil overfills. If it is overfilled and you are in the least bit concerned (and you must be since you started this thread), take it back to the dealer. A quick alternative, would be to pump out the overfilled amount with a dip stick pump. Cheap and easy to use. If that is not an option put the car up on ramps and drain enough out to get the level in the crosshatched area. If you take too much you can always add a little to adjust. All the dipsticks I have ever seen on any car or truck says "DO NOT OVERFILL." They don't say "Do Not Overfill Except for the Allowable Overfill." They do not say, "Don't Worry About Overfilling Just a Little Bit." They do not say, "Close the Hood and Forget It." I sleep well when the oil in my engines is within the safe zone on the dipstick.


Worry about 3oz over in a 6qt crankcase (195oz v 192oz).

I'll say it again just for you Close the hood and forget it.

 

[DIANgEMinONV]

Even a lot of dealerships overfill -- the last time I changed the oil at Honda dealer -- they overfilled it by about 3/4", which I considered significant, and decided to do it myself after that. This way it is way cheaper, and I have the assurance that it is done right, without overfilling, with the highest quality oil and filters.

 

[mojozoom]

My best overfill story is of a kid in our homeschool group who's doofus dad bought him a Z3. The kid brought it over to my house to do an oil change, so we slid the jack under the passenger side and jacked it up about 8", at which point oil started pouring out of the dipstick tube on the driver's side. He said it was dying at stoplights unless he kept it revved up.
It's happy now, but I was a little worried.

 

[JeffKeryk]

I help friends with basic services; sometimes more.
A dear friend rear ended another car, causing repairable damage to his 1997 Accord.
He was able to get the hood open and proceeded to add 2 quarts of oil and drove it home, less than 1/2 mile.

I asked him why????
He said just because.

We found another car shortly thereafter.

 

[GZRider]

Nothing to worry about. As a general rule your engine is safe from damage with an overfill or under-fill of 20% of the total oil capacity. So on an engine with a 5qt oil capacity, that's 1 qt. On a related note, on a 5qt engine the oil pressure light (warning light to the uninitiated) generally won't illuminate until 60-50% or less of capacity, which is long after damage has been done. When I sold cars we called that red lamp the Sell it at night light.

 

[Bud_One]

Used to worry about overfilling till we had a tech back in early 2000s overfill an Isuzu Rodeo 3.2L V6 with an extra 5 qts.

He had failed to drain the oil and filled it with 5 qts of oil . 10 qts of oil in a 5qt sump.

Customer drove it about a day or two and came back complaining about a vibration at 60MPH.

Two weeks later with many parts replaced - including driveshafts , wheels/tires , axle shafts etc. , the Isuzu engineer sent out to help us , pulled the dipstick and found the issue.

Drained the oil and refilled to 5qts and it was fine.

 

[GZRider]

That was prior to the extensive utilization of oil pressure based variable valve timing and or cam actuation (along with some other things), doing that to a modern turbo i4 or v6 would obliterate it.

 

[VolkswagenFox21]

I've overfilled every single oil change in my FRS by probably half a litre. It's fine. I once managed to overfill my brother's car by almost 2L several years ago and it's still going well. (Stupid mistake on my part, I looked at the wrong engine in the owner's manual).