Proper Z51 oil level
06-21-2014, 10:21 PM
#1
Pro
Thread Starter
Proper Z51 oil level
What is the proper oil level for a Z51? There are threads about the merits of catch cans. And apparently there was a recall/service bulletins about factory oil fill or pdi oil fill levels. I have a pretty early VIN (2297). Just got my first oil change at 1,600 miles with Mobil 1. What is the proper level when cold? Where is the right spot on the dip stick? Totally confused by threads on the forum. Thanks!
Thanks....
Thanks....
06-21-2014, 10:27 PM
#2
Moderator
There is no proper level when cold.
These vehicles have a
racetrack-ready dry sump engine
lubrication system. This high
performance system operates
differently than a standard engine
lubrication system and requires a
special procedure when checking
the engine oil level. Follow this
procedure closely.
The engine oil level must be
checked when the engine is warm.
Cold oil level in the dry sump tank
may not indicate the actual amount
of oil in the system. With this
system, engine oil is contained in an
external tank, separate from the
engine. Under normal operating
conditions, the oil pan under the
engine does not store any oil. If the
vehicle has been parked for an
extended period without the engine
being started, some oil will seep
back into the oil pan, reducing the
amount of oil held in the dry sump
tank and there could be no engine
oil at all showing on the dipstick.
This is normal since the dipstick is
designed to read the engine oil level
only after the engine has run long
enough to reach normal operating
temperature. Do not add engine oil
based on cold engine dipstick
readings. The engine oil level on the
dipstick will also be inaccurate if
checked while the engine is running.
1. To obtain an accurate engine oil
level reading, warm up the
engine to at least 80°C (175°F).
Cold oil will not give a correct oil
level reading.
2. Once the engine is warm, turn
off the engine. Checking the oil
while the engine is running will
result in an incorrect oil level
reading.
3. Check the oil level between five
and 10 minutes after the engine
is shut down.
4. Remove the dipstick from the
external engine oil tank and
clean it with a lint-free paper
towel or a cloth. Re-insert the
dipstick into the external oil tank,
pushing it all the way in until it
stops.
5. Remove the dipstick from the oil
tank and read the level on the
cross-hatched area.
If the oil is below the cross-hatched
area at the tip of the dipstick, add
1 L (1 qt) of the recommended oil
through the oil fill cap opening in the
oil tank and then recheck the level.
racetrack-ready dry sump engine
lubrication system. This high
performance system operates
differently than a standard engine
lubrication system and requires a
special procedure when checking
the engine oil level. Follow this
procedure closely.
The engine oil level must be
checked when the engine is warm.
Cold oil level in the dry sump tank
may not indicate the actual amount
of oil in the system. With this
system, engine oil is contained in an
external tank, separate from the
engine. Under normal operating
conditions, the oil pan under the
engine does not store any oil. If the
vehicle has been parked for an
extended period without the engine
being started, some oil will seep
back into the oil pan, reducing the
amount of oil held in the dry sump
tank and there could be no engine
oil at all showing on the dipstick.
This is normal since the dipstick is
designed to read the engine oil level
only after the engine has run long
enough to reach normal operating
temperature. Do not add engine oil
based on cold engine dipstick
readings. The engine oil level on the
dipstick will also be inaccurate if
checked while the engine is running.
1. To obtain an accurate engine oil
level reading, warm up the
engine to at least 80°C (175°F).
Cold oil will not give a correct oil
level reading.
2. Once the engine is warm, turn
off the engine. Checking the oil
while the engine is running will
result in an incorrect oil level
reading.
3. Check the oil level between five
and 10 minutes after the engine
is shut down.
4. Remove the dipstick from the
external engine oil tank and
clean it with a lint-free paper
towel or a cloth. Re-insert the
dipstick into the external oil tank,
pushing it all the way in until it
stops.
5. Remove the dipstick from the oil
tank and read the level on the
cross-hatched area.
If the oil is below the cross-hatched
area at the tip of the dipstick, add
1 L (1 qt) of the recommended oil
through the oil fill cap opening in the
oil tank and then recheck the level.
Last edited by Zymurgy; 06-21-2014 at 10:31 PM.
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scferris (07-16-2016)
06-21-2014, 10:34 PM
#3
Moderator
The original owners manual (and what is still in the online version) states the capacity with filter change is 10.3 qts. That was incorrect. There was an insert in the owners manual (and there is version B) both of which state the correct capacity as 9.8 qts.
Always follow the proper method to measure the oil level and make sure it is within the cross-hatched area on the dipstick.
Always follow the proper method to measure the oil level and make sure it is within the cross-hatched area on the dipstick.
06-21-2014, 10:38 PM
#4
Pro
Thread Starter
The original owners manual (and what is still in the online version) states the capacity with filter change is 10.3 qts. That was incorrect. There was an insert in the owners manual (and there is version B) both of which state the correct capacity as 9.8 qts.
Always follow the proper method to measure the oil level and make sure it is within the cross-hatched area on the dipstick.
Always follow the proper method to measure the oil level and make sure it is within the cross-hatched area on the dipstick.
The following users liked this post:
eddie1351 (08-04-2019)
06-21-2014, 11:34 PM
#5
06-21-2014, 11:52 PM
#7
I just did an oil and filter change letting all 3 holes (sump, tank and filter) drain for 30 minutes. It took exactly 9.4 qts to fill to 3/4 up on the hash marks, which is where I always run a dry sump to help reduce the "burp" phenomenon.
I suggest, if you have your dealer do the change, that you ask them to fill with 9 qts and give you the 5th to take home (you pay for all 10 anyway). Then, once home, let the car sit for 7-10 minutes and top off the tank to whatever level you are comfortable with, just don't go past the top hole on the dipstick.
My guess is 9.5 qts will usually be the magic number.
Hint: buy a funnel unless you have steady hands.
I suggest, if you have your dealer do the change, that you ask them to fill with 9 qts and give you the 5th to take home (you pay for all 10 anyway). Then, once home, let the car sit for 7-10 minutes and top off the tank to whatever level you are comfortable with, just don't go past the top hole on the dipstick.
My guess is 9.5 qts will usually be the magic number.
Hint: buy a funnel unless you have steady hands.
Last edited by mjw930; 06-21-2014 at 11:54 PM.
06-22-2014, 07:56 AM
#8
Melting Slicks
Rather than a funnel, I cut the bottom off a empty quart Mobil 1 bottle, turn it upside down and use that. The top fits perfect into the Z51 tank filler. Free funnel that actual works better.
06-22-2014, 09:43 AM
#9
07-16-2016, 01:31 PM
#10
Thanks Zymurgy, and others for your insights
I just bought a 2016 2LT Z51 and was looking at the dipstick last night. Immediately came back to the forum and bingo there is excatly the info needed. Many thanks to you all for your posts. I hope to return the favour soon. My other Vette is an 81 yellow coupe that my dad bought originally. Great emotional love for that car but the 2016 is quite simply the most compelling car I've ever driven.
07-16-2016, 08:23 PM
#11
E-Ray, 3LZ, ZER, LIFT
Member Since: Sep 2007
Location: NE South Carolina
Posts: 29,449
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What is the proper oil level for a Z51? There are threads about the merits of catch cans. And apparently there was a recall/service bulletins about factory oil fill or pdi oil fill levels. I have a pretty early VIN (2297). Just got my first oil change at 1,600 miles with Mobil 1. What is the proper level when cold? Where is the right spot on the dip stick? Totally confused by threads on the forum. Thanks!
Thanks....
Thanks....
The 5 minutes is to let the oil drip down from the baffles inside the dry sump tank. The tank does more than hold oil it has to separate the large amount of air that is also pumped from the crackcase. How else would you expect to get all the oil out!
The maximum 10 minutes is the oil in the tank drains back to the crackcase (thru the oil scavenge pump gears) and if you wait too long you'll get a false low reading. For fun, I checked the oil level before I started the car that had been sitting for several days. The oil level was below the bottom of the dip stick! That's more than 5 quarts low. So if you followed your "check cold idea," you would have added 5 quarts in that case! What a mess you would have created!
Now how much to add? First you should do what I have done for 50 years, check the level not go by volume. The 2014 Service Manual states clearly the volumes listed are only an estimate and the proper oil level must be determined by checking the level (per the manual.) It's the level that is critical in a wet or dry sump not volume!
That said since you no doubt will not add an optional clean side separator (my assumption from your questions) then you might follow with many of us do and that is fill to 1/2 way in the hatched area between MIN (add oil) and Max. Your choice, just means checking a bit more frequently.
Hope this is of some help with an understanding of why as well as what!
Last edited by JerryU; 07-16-2016 at 08:25 PM.
06-24-2017, 03:45 PM
#12
I swear I'm not an idiot, but I'm having a hell of a time with this dipstick and proper oil level. I waited 10 minutes after the car was turned off, checked the dipstick, and found it was about an inch under the first dot (about an inch under the cross lines). How low does that indicate I'm down?
06-24-2017, 03:53 PM
#13
E-Ray, 3LZ, ZER, LIFT
Member Since: Sep 2007
Location: NE South Carolina
Posts: 29,449
Received 9,606 Likes
on
6,619 Posts
^^^
Hmm, if you're oil level is one inch below the bottom hole (which is an inch under the hatched area) you're about a quart under the Min level. The Owner's Manual says add a quart when you are at the Min level.
Now, it's not real easy to read the dip stick especially with freshly filled oil. I often bring it out in the sun and rotate it like reading a thermometer! Read both sides. After a few 100 miles the oil picks up some color and is easier to read.
Many of us fill to half way in the hatched area. That is about a half quart over Min and a half quart under Max fill. This avoids oil spilling out with the burped air from the dry sump tank to the air intake tube (or it did until a change in the dry sump plumbing.)
Hmm, if you're oil level is one inch below the bottom hole (which is an inch under the hatched area) you're about a quart under the Min level. The Owner's Manual says add a quart when you are at the Min level.
Now, it's not real easy to read the dip stick especially with freshly filled oil. I often bring it out in the sun and rotate it like reading a thermometer! Read both sides. After a few 100 miles the oil picks up some color and is easier to read.
Many of us fill to half way in the hatched area. That is about a half quart over Min and a half quart under Max fill. This avoids oil spilling out with the burped air from the dry sump tank to the air intake tube (or it did until a change in the dry sump plumbing.)
Last edited by JerryU; 06-24-2017 at 04:02 PM.
06-24-2017, 04:06 PM
#14
I swear I'm not an idiot, but I'm having a hell of a time with this dipstick and proper oil level. I waited 10 minutes after the car was turned off, checked the dipstick, and found it was about an inch under the first dot (about an inch under the cross lines). How low does that indicate I'm down?
The oil drains relatively quickly from the dry sump tank back to the oil pan. If you check it at 5 minutes, it can be up to 1/4 qt. higher than after 7-8 minutes and after 10 minutes, you could be half qt. lower than your reading at 5 minutes. If it's much after 10 minutes, you're likely to have a very false reading, and an indication that when you're a quart low when you may not be.
I set the timer on my watch and check it between 7-8 minutes so I always have a consistent reading. That's the only way you can possibly monitor oil consumption ( or not) accurately.
Last edited by Foosh; 06-24-2017 at 04:10 PM.
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GEBackbone (06-28-2017)
06-24-2017, 04:13 PM
#15
Le Mans Master
The explicit instructions are to check BETWEEN 5 and 10 minutes after shutdown from an oil temp above 175ºF, not after 10 minutes.
The oil drains relatively quickly from the dry sump tank back to the oil pan. If you check it at 5 minutes, it can be up to 1/4 qt. higher than after 7-8 minutes and after 10 minutes, you could be half qt. lower than your reading at 5 minutes. If it's much after 10 minutes, you're likely to have a very false reading, and an indication that when you're a quart low when you may not be.
I set the timer on my watch and check it between 7-8 minutes so I always have a consistent reading. That's the only way you can possibly monitor oil consumption ( or not) accurately.
The oil drains relatively quickly from the dry sump tank back to the oil pan. If you check it at 5 minutes, it can be up to 1/4 qt. higher than after 7-8 minutes and after 10 minutes, you could be half qt. lower than your reading at 5 minutes. If it's much after 10 minutes, you're likely to have a very false reading, and an indication that when you're a quart low when you may not be.
I set the timer on my watch and check it between 7-8 minutes so I always have a consistent reading. That's the only way you can possibly monitor oil consumption ( or not) accurately.
06-24-2017, 04:48 PM
#16
The explicit instructions are to check BETWEEN 5 and 10 minutes after shutdown from an oil temp above 175ºF, not after 10 minutes.
The oil drains relatively quickly from the dry sump tank back to the oil pan. If you check it at 5 minutes, it can be up to 1/4 qt. higher than after 7-8 minutes and after 10 minutes, you could be half qt. lower than your reading at 5 minutes. If it's much after 10 minutes, you're likely to have a very false reading, and an indication that when you're a quart low when you may not be.
I set the timer on my watch and check it between 7-8 minutes so I always have a consistent reading. That's the only way you can possibly monitor oil consumption ( or not) accurately.
The oil drains relatively quickly from the dry sump tank back to the oil pan. If you check it at 5 minutes, it can be up to 1/4 qt. higher than after 7-8 minutes and after 10 minutes, you could be half qt. lower than your reading at 5 minutes. If it's much after 10 minutes, you're likely to have a very false reading, and an indication that when you're a quart low when you may not be.
I set the timer on my watch and check it between 7-8 minutes so I always have a consistent reading. That's the only way you can possibly monitor oil consumption ( or not) accurately.
06-24-2017, 05:07 PM
#17
Race Director
I know I've said this before when this topic comes up, but I really think that GM needs to adopt an electronic dipstick for the dry sump cars so that there is no doubt you have exactly how much oil you need. I love that feature on my wife's BMW! I just changed the oil in her car today actually, and I know from past oil changes that if I put exactly 7 quarts in it, the display on the dash will show the level right at the max point. When that level moves down by one notch, I add a 1/4 of a quart and it brings it back to the max again. Easy peasy, lemon squeezy! 
I have never really trusted dipsticks on a lot of the GM cars that I have owned as they can be hard to read in some cases. My 98 Corvette was a perfect example, when I first got the car I kept checking the oil and was happy to see that the level never dropped, but after owning the car a while and having done a few oil changes on it I once decided to measure exactly how much oil came out when I drained it. Even though the dipstick showed the level to be full, upon measuring it I found it a quart low! So my method with my cars now (except the BMW) is to put in exactly what the manual calls for at oil change time, measuring how much comes out at the end, and determining my consumption rate based on that, so I know how much and how often I need to add oil. That method works as long as the consumption rate doesn't drastically change all at once, but a well cared for engine shouldn't do that anyhow.
I have never really trusted dipsticks on a lot of the GM cars that I have owned as they can be hard to read in some cases. My 98 Corvette was a perfect example, when I first got the car I kept checking the oil and was happy to see that the level never dropped, but after owning the car a while and having done a few oil changes on it I once decided to measure exactly how much oil came out when I drained it. Even though the dipstick showed the level to be full, upon measuring it I found it a quart low! So my method with my cars now (except the BMW) is to put in exactly what the manual calls for at oil change time, measuring how much comes out at the end, and determining my consumption rate based on that, so I know how much and how often I need to add oil. That method works as long as the consumption rate doesn't drastically change all at once, but a well cared for engine shouldn't do that anyhow.
06-24-2017, 05:28 PM
#18
Patman,
You raise a very interesting and controversial topic on car forums. I've owned two vehicles (Jaguar F-Type and BMW M3) w/ only an electronic means of checking oil level. On those forums, a very large percentage of owners complain about not having an old-school dipstick because they don't trust them.
I'm personally agnostic. I was OK w/ the electronic systems, but I have to say, I feel better checking it the old-fashioned way.
You raise a very interesting and controversial topic on car forums. I've owned two vehicles (Jaguar F-Type and BMW M3) w/ only an electronic means of checking oil level. On those forums, a very large percentage of owners complain about not having an old-school dipstick because they don't trust them.
I'm personally agnostic. I was OK w/ the electronic systems, but I have to say, I feel better checking it the old-fashioned way.
06-24-2017, 05:29 PM
#19
The explicit instructions are to check BETWEEN 5 and 10 minutes after shutdown from an oil temp above 175ºF, not after 10 minutes.
The oil drains relatively quickly from the dry sump tank back to the oil pan. If you check it at 5 minutes, it can be up to 1/4 qt. higher than after 7-8 minutes and after 10 minutes, you could be half qt. lower than your reading at 5 minutes. If it's much after 10 minutes, you're likely to have a very false reading, and an indication that when you're a quart low when you may not be.
I set the timer on my watch and check it between 7-8 minutes so I always have a consistent reading. That's the only way you can possibly monitor oil consumption ( or not) accurately.
The oil drains relatively quickly from the dry sump tank back to the oil pan. If you check it at 5 minutes, it can be up to 1/4 qt. higher than after 7-8 minutes and after 10 minutes, you could be half qt. lower than your reading at 5 minutes. If it's much after 10 minutes, you're likely to have a very false reading, and an indication that when you're a quart low when you may not be.
I set the timer on my watch and check it between 7-8 minutes so I always have a consistent reading. That's the only way you can possibly monitor oil consumption ( or not) accurately.
06-24-2017, 05:37 PM
#20
Vince,
OK, if I were you I'd add one full quart, and check again.
On the clutch fluid, top it off w/ non-synthetic, DOT 4, then start the "Ranger method."
Cliff Notes Ranger Method:
1) With a syringe, suck out the fluid in the bowl, refill, put cap back on,
2) Pump clutch pedal 25 times,
3) Repeat steps 1 and 2 about 10 times.
If you do the above, and then exchange 1-2 bowls a month, your clutch fluid will always be fresh.
OK, if I were you I'd add one full quart, and check again.
On the clutch fluid, top it off w/ non-synthetic, DOT 4, then start the "Ranger method."
Cliff Notes Ranger Method:
1) With a syringe, suck out the fluid in the bowl, refill, put cap back on,
2) Pump clutch pedal 25 times,
3) Repeat steps 1 and 2 about 10 times.
If you do the above, and then exchange 1-2 bowls a month, your clutch fluid will always be fresh.