Overfilled from the factory?

[Hall]

The thing us that different people wait different time for the oil to drain. Usually, people who overfill are those who don't wait enough.

I check the oil in our cars after they've sat, typically overnight, and haven't been running for 8+ hours. If I have reason to worry that an engine might be low on oil and I can't wait that long, I'll check it and read it and as long as I get a fairly clean 'line' on the dipstick and no smearing all over the rest of it, if there's oil on the dipstick and at or above the 'low' marking, I call it good. Letting it drain longer will simply show it closer to the middle.

 

[Hall]

I do the same—I change my oil when car's front is a bit jacked up on stands. It's not horizontal. That may contribute for some oil unable to be poured out vs people who change their oil when their car is completely horizontal as on a lift.

That could explain why 5 quarts was enough to show properly filled on the dipstick on mine when it spec'd 5.25 quarts. Oh no ! I was always leaving 1/4 quart of old oil in ! In all seriousness though, it also depends where the oil drain plug is. If it's at the back of the pan, when on ramps, it's all coming out. If it's at the front, you'll definitely leave some in as well as if it's on the side of the pan.

Then we have those (some here !) who lower their vehicle or even raise the other end, then let it continue "draining" overnight, to get even more out !

 

[ammolab]

If they're changing their own oil, my money says the vast majority of them are in fact checking the manual.

Plenty of YOU-TUBE addicts change their own oil. Manuals, books etc not a habit for them. Info they receive is all over the place.

 

[ARCOgraphite]

I disagree. I think being a half quart over is better than being a half quart under (unless it’s a severe fuel diluter)

Why? What are your thoughts or experience?

Maybe it's a Subaru thing for our stable of cars; with the piston way down there sideways and living on a steep hill. Or a parade of small pan and block 4 bangers with a crowded sump. All will be engine specific as of their "sensitivity" to overfill.

Or my 50 previous years of drag racing or nutty street antics. You never want to foam the oil in severe attitude or high G driving. and conversely the chance of uncovering a pickup on the street is remote to never running a 1/2 qt low. Most Owners manuals have a caution notice in the O.C. service section to remove any overfill or resultant engine damage will not be covered by warranty.

I wont argue on these pages that 1/2qt is anything more than rounding error on many engines. But personally I fiddle if the engine seems to balk after performing an OC, and time and miles is not improving things. There may also be some unknowns or un-thought-a-bouts like crankcase volume changing PCV resonances affecting air metering.

Is your Vette a LS3 or the 9 with the 10 qt dry sump? That won't matter a bit.

How 'bout an LS3 with 6 Qt pan? Now you will have trackside stories. about overfill or underfill blowing things up.

- Old Arco

 

[Patman]

Why? What are your thoughts or experience?

Maybe it's a Subaru thing for our stable of cars; with the piston way down there sideways and living on a steep hill. Or a parade of small pan and block 4 bangers with a crowded sump. All will be engine specific as of their "sensitivity" to overfill.

Or my 50 previous years of drag racing or nutty street antics. You never want to foam the oil in severe attitude or high G driving. and conversely the chance of uncovering a pickup on the street is remote to never running a 1/2 qt low. Most Owners manuals have a caution notice in the O.C. service section to remove any overfill or resultant engine damage will not be covered by warranty.

I wont argue on these pages that 1/2qt is anything more than rounding error on many engines. But personally I fiddle if the engine seems to balk after performing an OC, and time and miles is not improving things. There may also be some unknowns or un-thought-a-bouts like crankcase volume changing PCV resonances affecting air metering.

Is your Vette a LS3 or the 9 with the 10 qt dry sump? That won't matter a bit.

How 'bout an LS3 with 6 Qt pan? Now you will have trackside stories. about overfill or underfill blowing things up.

- Old Arco

I’ve overfilled a few of my cars with no ill effects. My C5 Corvette manual said to add one extra quart if you were racing so I just started running one extra quart always. Had that car for 9 years with no problems and lots of drag racing too actually (it ran a best of 12.81 at 109.4)

I ran about a half quart extra in my C6 Corvette with the LS2 engine.

Some cars have problems with oil starvation if you run them a bit low, the Subaru BRZ (and it’s twins) come to mind.

My current Corvette is the LT1 and it’s the wet sump version so it holds 7 quarts. I often run it a half quart over.

I just don’t like the idea of being even a half quart low, especially if that engine only holds 4 quarts to begin with.

 

[ARCOgraphite]

I’ve overfilled a few of my cars with no ill effects. My C5 Corvette manual said to add one extra quart if you were racing so I just started running one extra quart always. Had that car for 9 years with no problems and lots of drag racing too actually (it ran a best of 12.81 at 109.4)

I ran about a half quart extra in my C6 Corvette with the LS2 engine.

Some cars have problems with oil starvation if you run them a bit low, the Subaru BRZ (and it’s twins) come to mind.

My current Corvette is the LT1 and it’s the wet sump version so it holds 7 quarts. I often run it a half quart over.

I just don’t like the idea of being even a half quart low, especially if that engine only holds 4 quarts to begin with.

Thanks, Patman.

 

[Vexorg]

Question: for those that have worked at dealership, is oil level on new vehicles off truck something you check? Wonder if overzealous dealership maybe added oil it didn’t need.

Part of the PDI is to check all fluid levels. Safe levels on the dipstick have some level of interpretation depending on the tech doing the PDI. Being slightly overfull is no issue, being 50% over full is.