Question: How Much Excess Oil Is Too Much...?

[timfitz63]

OK. This is probably going to come across as a bit anally-retentive; but I'm an engineer, so try not to hold it against me...

Recently had the oil changed on my 'Vette. I supplied my trusted independent mechanic shop with all the oil and a filter, and just had them do the oil change while they were performing the annual Texas state inspection.

The quantity of oil with which I supplied them was somewhere between the recommended 6.5 quarts and 7 quarts (four 1-quart bottles; and approximately 2.75-3 quarts in a 5-quart jug that I had remaining from a previously oil change). In spite of my instructions to use only 6.5 quarts and return the remainder (0.25-0.5 quart) to me, they dumped all of it in... I was a bit miffed, although the dipstick seemed to show the level just at the top of the 'fill band' (which I realize is the real indicator of oil capacity -- although it's somewhat difficult to tell with new oil and the "slop" that seems to get dragged up the dipstick when you pull it out); and the oil pressure gauge indicated normally during the drive home. And I realize some of the oil gets 'soaked up' and contained inside the new oil filter; but that's not a particularly big oil filter on the C5...

So, I've potentially got 0.25-0.5 quarts of extra oil in the crankcase. Already knowing too much oil can be bad (and with the Owner's Manual dire warning about overfilling the oil in a big, bold font), I thought I'd pose the question: exactly how much excess oil is too much for the LS1...? Consultation of various online resources doesn't really answer the question directly; most acknowledge the amount of my overfill should not pose any issues (which is how I tend to lean on the topic); but there are a few naysayers that maintain even a little can lead to serious problems, depending on the engine and oil pan design.

So: what say the C5/LS1 gurus...?

 

[timfitz63]

Bump.

59 views and counting, but not one opinion...? Did I stump everyone...?

 

[LLC5]

59 views and counting, but not one opinion...? Did I stump everyone...?

Ok, I'll jump in. I don't believe any damage will occur to your LS1 with a 1/2 quart oil over fill. If it were mine though I would not want it more that 1/4 quart over.

 

[Junkman2008]

You're being anal. If you were to track your car, it is sometimes recommended that you add .5 quart of oil to the engine. Thus, the amount that you're over won't do any damage. The way some C5's eat oil, I won't be surprised to see that amount burned off in a little time.

 

[6 Shooter]

My GMPP LS6 Crate Engine doesn't eat/use any freaking oil and It's driven hard!

:cool

GMPP LS6 Crate Engine
​

 

[Junkman2008]

That's why I said "SOME" C5's...

Also, C5's came stock with LS1's or 2's.

 

[Hib Halverson]

If you have half a pint to a pint too much oil in the engine, it is unlikely it will cause any problems.

But....if you want to drain out a small quantity, here's what to do.

I monitor my engines' oil use as part of a test program of which I am a part. If I overfill an engine by even a slight amount, it throws off the accuracy of my testing, so when I screw up and overfill a little bit, I get the car/truck up on stands. I put a small funnel in an oil bottle. I unscrew the oil drain plug all the way but hold the end of the plug in the oil pan drain hole,. Then I tip the drain plug up slightly so oil begins to drain into the bottle at a modest rate. When I think I have about what I need to drain out in the bottle, I thread the plug back into the pan and tighten it.

This works every time with messes.

Hope that helps.

 

[6 Shooter]

WOW - Wrong Again!

That's why I said "SOME" C5's...

Also, C5's came stock with LS1's or 2's.

They only came "stock" with LS1's & LS6's!

​

 

[Junkman2008]

They only came "stock" with LS1's & LS6's!

​

My bad, you're right. Typo.

 

[VETTEX2]

LiquiVac - Do It Yourself Oil Change System (Oil Extractor Pump) - LiquiVac

 

[timfitz63]

You're being anal...

Wouldn't be the first time; probably won't be the last...

... If you were to track your car, it is sometimes recommended that you add .5 quart of oil to the engine. Thus, the amount that you're over won't do any damage. The way some C5's eat oil, I won't be surprised to see that amount burned off in a little time.

I haven't noticed any oil consumption in my engine, but have heard that some will added a half quart or so for autocross. So I wasn't particularly concerned about the amount of overfill I got.

Still am curious just how much is too much, though...? I realize it will vary based on the engine and pan designs, but was mainly wondering if there was a 'rule of thumb,' as it were: a quarter quart is OK; half a quart is OK, but less desirable; a quart is probably not good; etc.

... when I screw up and overfill a little bit, I get the car/truck up on stands. I put a small funnel in an oil bottle. I unscrew the oil drain plug all the way but hold the end of the plug in the oil pan drain hole,. Then I tip the drain plug up slightly so oil begins to drain into the bottle at a modest rate. When I think I have about what I need to drain out in the bottle, I thread the plug back into the pan and tighten it...

Unfortunately, this is a bit of a chore for me, as I have no jacking equipment or stands. Perhaps I should invest in a set and start doing the oil changes myself to avoid future angst...?

LiquiVac - Do It Yourself Oil Change System (Oil Extractor Pump) - LiquiVac

Thought of one of those; they would seem to come in handy for these kinds of situations, but had yet to stumble across one as I perused the auto parts stores... However, I see now from the web site you posted that I need to check places like Home Depot and Lowe's instead... Guess these things are mainly intended for lawn & garden equipment...

Thanks all for the input and reassurance!

 

[Dad]

The owners manual (2-22) says if you are using your vehicle for racing to keep the oil "at on near one quart above the upper mark that shows proper operating range on the engine oil dipstick". Although you may not be racing it the slight overfill doesn't look like it would be a problem.

 

[timfitz63]

The owners manual (2-22) says if you are using your vehicle for racing to keep the oil "at on near one quart above the upper mark that shows proper operating range on the engine oil dipstick". Although you may not be racing it the slight overfill doesn't look like it would be a problem.

Well, I'll be! Sure enough, that's what the 2004 Manual says as well (on p. 2-23)! The 1998 Manual is a bit more vague, but essentially hints at the same thing on p. 2-24.

Looks like you may have found the definitive answer!

What's a bit baffling, though, is that the 2004 Owner's Manual tells you to remove the excess oil after you've finished participating in competitive driving... Hmm...

Maybe I should just drive competitively everywhere I go until my next oil change...?

 

[Junkman2008]

Wouldn't be the first time; probably won't be the last...

There's nothing wrong with being anal. I am too. Have you seen my technical write-ups? Anal is my badge of honor.

 

[timfitz63]

There's nothing wrong with being anal. I am too. Have you seen my technical write-ups? Anal is my badge of honor.

Actually, I have seen your write-ups; very thorough!

Being an engineer, anal just seems to come naturally to me. But I guess that's a desirable characteristic for those who are designing skyscrapers and bridges -- or (in my case) testing aircraft for acceptance/certification...!

 

[6 Shooter]

Drive it like ya stole it!

Maybe I should just drive competitively everywhere I go until my next oil change...

​

 

[gmjunkie]

There's nothing wrong with being anal. I am too. Have you seen my technical write-ups? Anal is my badge of honor.

Your Anal Alright!~!!:L
Junkman is the only guy I know that has the chef grind up lots of Hot Peppers in the Pizza Sauce before they put the Toppings on!~!!
eek:eek
The next morning I was yelling "Come on Ice Cream"!~!!

 

[Junkman2008]

Actually, I have seen your write-ups; very thorough!

Being an engineer, anal just seems to come naturally to me. But I guess that's a desirable characteristic for those who are designing skyscrapers and bridges -- or (in my case) testing aircraft for acceptance/certification...!

I blame mine on the Marine Corps.