MY Z51 Stingray Corvette was serviced today. Oil level is now 1/4 inch above hatch marks. Waiting to hear from Dealer. Chevrolet Customer
Service could NOT answer my question. Is 1/4 inch bad?

 

Ok From what I know---- did you check it after it was up to temp AND then wait 5 min. for it to cool & drain before checking the level?
This is the recommended way to check.

 

Yes, followed instructions as I always do...wish the Dealer did. I have calculated that they overfilled my system with 6.4 ounces of oil. No one can tell
me if this amount is serious or no problem. They should have used 9.8 quarts and the guy probably put in all 10 quarts!

 

 

Not a big deal. The manual tells you to add about that much additional oil for track days. Look for that in manual.

 

Leave it.

 

The overfill issue comes into play when they add several quarts extra due to improper draining.

 

over the hash marks is not ok. Overfilling will cause issues. I had a dealer tell me they fill all the dry sumps with 10 quarts, and don't care. I started going to a different dealer.
I asked Paul Koerner why it's bad to overfill and he explained in detail, and I promptly forgot! But, something along the lines of foaming up the oil, as well as oil getting into intake.
Ask the dealer nicely to correct it, and if they can't put the correct amount next time, find another dealer.

My dealer puts in 9 quarts, gives me the 10th quart in the Mobil 1 bottle, so that I can drive home, and check the level after it's warmed up.

9 quarts gets you in the hash marks, and then you can top off after getting home.

 

My dealer always puts in 9 qts. and gives me the 10th one. This puts the oil level 1/2 way on the dipstick hash marks where it stays till the next change. Have 4 qts. in stock now and will only have to buy 5 for my next change.

 

9.8 qts. is the published spec for a completely empty system. Once filled, you'll never get all the old oil out even if you let it drain for several hours, which a service department simply cannot afford to do. The best they can generally do is drain for about 10-15 minutes, if that.

It's been published here 100s of times that the smartest thing you can do get it documented on the service invoice to fill with "9 QUARTS ONLY" and adjust the level if necessary later. Mine is always exactly halfway between the two hash marks after an oil change, which is where I keep it.

To the OP, you can buy a cheap oil extractor on Amazon for under $20, and suck out the excess from the dry sump tank.

 

Mine was delivered to me the exact same way, not sure if it was overfilled from the factory or if during pdi the tech checked the oil outside of the ten min after shut down window and added oil thinking it was low.

Regardless, filling the engine over the hash marks can cause damage to the engine - it can lead to aerated oil (air bubbles in the oil) which can result in parts of your engine not getting the lubrication they need, which can result in very bad things, man. I just went to the store, bough some plastic tubing in the fish section (cost like 3-5 bucks), put it into my dipstick tube and siphoned out about a half quart of oil to get the level inside the hash marks.

For the 500 mile change, I had them put in 9L (the new oil is only available in liters atm...) and had them give me the 10th liter bottle. Checked oil when I got home and the level was right between the hash marks.

 

Per my 2014 Manual:

Track Events and
Competitive Driving
Participating in track events or other
competitive driving without following
the instructions provided may affect
the vehicle warranty. See the
warranty manual before using the
vehicle for racing or other
competitive driving.
Refer to Competitive Driving Mode
on page 9-42.
Be sure to follow all service
procedures before driving the
vehicle at track events or
competitively.
{Caution
If the vehicle is used for track
events and competitive driving,
the engine may use more oil than
it would with normal use. Low oil
levels can damage the engine.
Check the oil level often and at
the proper level. See Engine Oil
on page 10-10.
Additional oil fill above the upper
mark on the dipstick is not
recommended for track events or
other competitive driving.
Because engine oil temperatures
will be higher, it is necessary to use
a higher viscosity engine oil for
racing or other competitive driving.
See Recommended Fluids and
Lubricants on page 11-12.

I run my oil dead middle range of the hash pattern on the dipstick.

Elmer

 

Word of caution is that 9L is 9.5 qts. If not drained well, you could end up overfilled that way as well.

 

 

Neil, on a side note...I see you are driving your Vette to Carlisle from Florida. I am also driving my Vette up to Carlisle from Florida. Are you traveling with a group? I was wondering if there might be a mini caravan cruising up there together? Thanks.

Charlie

 

Thats aeration, and it only occurs on wet sump engines. Imagine the "sump," or oil pan on the bottom of the engine holding all the oil. When the pan is overfilled, the oil reaches up to the bottom of the rotating crank and con-rods, and the rotating mass whipping the oil into a foam. That foam does not travel through the oil pump as pressurized oil, thus dropping oil pressure to zero and the various valve train parts that require lubrication goes dry...BOOM goes the engine.

On a dry sump, the small oil pan on the bottom of the engine never holds too much oil. Basically whatever that is drained to the bottom of the "sump" is pumped right back into the separate reservoir. Hence the "dry" in dry sump. Overfilling a dry sump has its own set of challenges, but a dry sump is far more forgiving when it comes to overfills than a wet sump. In a dry sump, when you overfill TOO much, like when you take your measurement of the oil when cold, and see that it's at the minimum mark, and fill it back up? There's already oil that drained back into the sump, oil in the passageways, and oil in the reservoir. The end result is as the oil heats up and expands, there's no room for it to go (since the reservoir, sump, and pathways are all full). There's already a baseline of pressure in the oiling system, and as the oil pump start pumping oil through the system, oil pressure exceeds what the system is designed for, and ...BOOM goes the engine.

But a typical dry-sump system has a big enough reservoir where a slight overfill is not going to destroy the engine. In fact, the manual (as some has already stated) calls for an extra 1/2 quart for motorsport applications, and it's the common recommendation for dry-sump engines to add 1/2 quart for track use (BMW's E46 M3, using the S54 engine, which has a scavenger pump acting as a semi-dry pump setup, calls for adding 1/2 L of oil for motorsport applications as well). A few ounces overfill on a dry sump isn't the end of the world. In fact, a few ounces of overfill on a WET sump isn't the end of the world either.

The problem with dry sump, is of course, HOW to measure the oil level. Because the small sump at the bottom of the reservoir remains "dry" during operation of the engine (or with minimum oil), if you measure IMMEDIATELY after engine shut-down the reservoir will measure too high. If you wait overnight, the oil pump stops supplying scavenging pressure, and oil drains back into the sump from the reservoir, and you'll measure LOW. Hence the complicated "wait 5-10 minutes after engine shut-off" dance to get an accurate reading.

I PERSONALLY think, if you don't want to deal with the dealership filling in 10 bottles and calling it a day, you do your own oil change to make sure the RIGHT amount is poured in. Otherwise, it's not the end of the world if it's a few ounces above the max mark on a dry sump, IMO.

 

 

Aeration via overfill only occurs on WET SUMP engines. Dry sump oil pumps were designed partly to prevent that.

 

 

No, going by myself because I go early Wednesday and meet friends from Connecticut.