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2012 Grand Sport Wet Sump Oil Capacity.

BVIPER

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Did my first oil and filter change @ 500 miles. I had it on the lift and let drain for over an hour. Installed new AC oil filter and filled with Mobil 1 5W-30. The owners manual says capacity is 6 quarts with oil and filter change. I filled the oil filter with oil and then added 5 quarts, started and checked for leaks. Let sit and then checked again. It only took a half quart to bring it up to full on the dipstick. Let it sit overnight to check it cold and it still shows full on the dipstick. I haven't added the remaining half quart.
When the car was delivered with 7 miles on the odometer, it showed half quart over full on the dipstick when checking it cold. I drained a half quart to bring it down to the full mark.
I just talked to another GS owner and he has experienced the same on his first oil change and also said his car was also delivered a half quart over full, but he left it alone.
Is the owners manual worng? Should I add the remaining half quart, so I have 6 quarts?
 
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I believe the 'other half a quart' is in the oil filter you filled before installing it.

That's the way it works for me anyway.

Btw, :welcome
 
I believe the 'other half a quart' is in the oil filter you filled before installing it.

That's the way it works for me anyway.

Btw, :welcome


Hi Tuna.

Thanks for the welcome.
I probably did a poor job of describing what I did, but the total amount of oil that I have put into the engine, including the filter, is 5.5 quarts. My dipstick currently shows full, right at the top of the cross hatch on the dipstick. I still have a half empty bottle of Mobil 1, so I know I measured correctly. It just seems odd that I spoke with another 12 GS wet sump owner who has encountered the same situation.
Maybe Hib can offer his thoughts. When I did a search of this forum, I saw he owns a GS, although not sure if his is a wet sump.

Brian
 
Hi Tuna.

Thanks for the welcome.
I probably did a poor job of describing what I did, but the total amount of oil that I have put into the engine, including the filter, is 5.5 quarts. My dipstick currently shows full, right at the top of the cross hatch on the dipstick. I still have a half empty bottle of Mobil 1, so I know I measured correctly. It just seems odd that I spoke with another 12 GS wet sump owner who has encountered the same situation.
Maybe Hib can offer his thoughts. When I did a search of this forum, I saw he owns a GS, although not sure if his is a wet sump.

Brian

Mine's a Z06, but I've researched the service manual and it says six quarts for LS3 wet sump motors, too. Let me make a few inquiries with my pals at GM.

For now, you're not going to have any big problems at 1/2 qt. over full.

One question...what oil filter are you using?
 
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For me, I always considered the manual just an approximation as to what the amount of oil required is, so I've never actually put 6 total quarts in my LS3 cars (or LS1 or LS2 or LS6 or LSA cars) then checked the dip stick.

I've always filled the filter, like you, and then added one quart less to the pan than what the manual says. After running the engine, I top off the oil until the dip stick says it is full. I bet I've not been putting in the full 6 quarts either when doing it this way.
 
Mine's a Z06, but I've researched the service manual and it says six quarts for LS3 wet sump motors, too. Let me make a few inquiries with my pals at GM.

For now, you're not going to have any big problems at 1/2 qt. over full.

One question...what oil filter are you using?

Hib.

Thank you for your reply. I look forward to hearing what you find out from your pals at GM.
I installed a AC PF48 oil filter.
For now, I have not put in the last .5 quart of oil.
Please note, when I am checking the oil level, I am doing it with the engine cold. I read the instructions in the owners manual for checking both the wet and the dry sump oil levels. The dry sump instructions say it must be done with the engine warm, but in the instructions for the wet sump, there is no such distinction, other than to say wait a few minutes before checking the oil level if the car has been running.

Brian
 
Hib.

Thank you for your reply. I look forward to hearing what you find out from your pals at GM.
I installed a AC PF48 oil filter.
For now, I have not put in the last .5 quart of oil.
Please note, when I am checking the oil level, I am doing it with the engine cold. I read the instructions in the owners manual for checking both the wet and the dry sump oil levels. The dry sump instructions say it must be done with the engine warm, but in the instructions for the wet sump, there is no such distinction, other than to say wait a few minutes before checking the oil level if the car has been running.

Brian

Ok.
You got the right filter. I was thinkin', if you had a different filter, maybe that'd be a possible explanation.

I don't have an Owner's Manual handy for a '12 as mine is in the car, stored at another location while we're pouring a new driveway/parking area, but the Factory Service Manual, which I have here at the office, says that all "capacities" listed are "approximate" so, does that mean ±0.5qt? Who knows.

With a wet sump motor, here's what the FSM says to do after the oil is drained and the old filter is removed.

>Install the oil filter and tighten to 30Nm
>Install the drain plug and tighten to 25Nm
>Lower the vehicle.
>Fill the engine with the appropriate amount (ie: 6-qts) and type of engine oil
>Start the engine and check for leaks
>Shut off the engine and check the oil level
>Install the oil cap
>Close the hood
>Reset the oil life monitor

The above implies that the filter drains overnight, so I'd run the engine until the ECT comes up, shut it off then check the oil. If you're down half a quart, put the rest in.

For reference, the GM says, with the dry sump motors, to wait 2-5-min. after shutdown to check the oil.

Lastly, I'll offer this suggestion...unless your driving the car in very cold weather, you're going to have better long-term durability if you go to a 10W30 rather than the factory-fill 5W30. The downside of that will be a very, very small decrease in fuel mileage, perhaps a 1/10-th to 1/4-th MPG. Not sure what Costco sells were you are but out west, Costco sells both Mobil 1 5W30 and 10W30. Mobil 1 is good oil but the best is an ester-based synthetic. I use Red Line 10W30.

Hope that helps.
 
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Ok.
You got the right filter. I was thinkin', if you had a different filter, maybe that'd be a possible explanation.

I don't have an Owner's Manual handy for a '12 as mine is in the car, stored at another location while we're pouring a new driveway/parking area, but the Factory Service Manual, which I have here at the office, says that all "capacities" listed are "approximate" so, does that mean ±0.5qt? Who knows.

With a wet sump motor, here's what the FSM says to do after the oil is drained and the old filter is removed.

>Install the oil filter and tighten to 30Nm
>Install the drain plug and tighten to 25Nm
>Lower the vehicle.
>Fill the engine with the appropriate amount (ie: 6-qts) and type of engine oil
>Start the engine and check for leaks
>Shut off the engine and check the oil level
>Install the oil cap
>Close the hood
>Reset the oil life monitor

The above implies that the filter drains overnight, so I'd run the engine until the ECT comes up, shut it off then check the oil. If you're down half a quart, put the rest in.

For reference, the GM says, with the dry sump motors, to wait 2-5-min. after shutdown to check the oil.

Lastly, I'll offer this suggestion...unless your driving the car in very cold weather, you're going to have better long-term durability if you go to a 10W30 rather than the factory-fill 5W30. The downside of that will be a very, very small decrease in fuel mileage, perhaps a 1/10-th to 1/4-th MPG. Not sure what Costco sells were you are but out west, Costco sells both Mobil 1 5W30 and 10W30. Mobil 1 is good oil but the best is an ester-based synthetic. I use Red Line 10W30.

Hope that helps.


Hib.

I am working from home today, so I had an opportunity to do as you suggested. The GS hadn't been run for a few days, so I verified the oil level showed full on the dip stick when cold. I then started it, let it idle until the oil temperature came up to 175 degrees. Shut it off and let it sit for 5 minutes. I then checked the oil level. The oil level was at the center hole on the dipstick. Added my remaining half quart and it now shows full. I wonder how many people are doing what I did and drained half a quart from their wet sump engines when delivered new, assuming the dealer over filled it, or only put in 5.5 quarts after an oil change when checking the engine cold? On every wet sump sports car I have ever owned, I always checked the oil level when the engine was cold. This is a first for me. Maybe our bow tie brethern should take a look at revising the instructions in the owners manual? Maybe even send out a TSB or owners manual supplement to address this.
I will still be interested in what your pals at GM have to say.
Thank you very much for your time and effort. I greatly appreciate it. Attached is a picture of my GS.

PS I am a big fan of Red Line Oil. I also believe that 10w-30 would be a better choice for my application. The dilema I have is that the owners manual states only use Dexos1 and also specifically says only to use 5W-30. My concern is that if I were to have a warranty claim related to the engine, I would have a big fight on my hands if I were to deviate from their recomendation.

Brian

2012 Grand Sport-7.jpg
 
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Hib.

Just curious if you heard anything back from your friends at GM about checking oil level cold versus warm?
Thanks
Brian
 
Hib.

Just curious if you heard anything back from your friends at GM about checking oil level cold versus warm?
Thanks
Brian

We've been discussing that extra half a quart via email. He works in the part of GM which deals with after-sales service issues so he's in the know. He thinks he's got a handle as to why the half quart difference but he's still confirming the info. Once he gets back to me, I'll post the explanation.

As to when to check the oil, I've already resolved that question to my satisfaction with what's in the FSM. See the above post about the wet-sump oil checking procedure.
 
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Hib.

Thanks for the update.
I have been doing some searching on the other Corvette forums on this subject and have found several posts from people who encountered the same situation and asked the same question. Most of the replys are pretty generic and suggest just adding the full 6 quarts and not being concerned about showing a half quart overfull when checking the oil level cold.
One thing I did find out is in the owners manual for a 2010 wet sump engine, section 6-19, the procedure for checking the oil level in the wet sump engine is different than the procedure for checking the 2012 wet sump engine, section 10-14. In 2010 it states the oil must be warm, in the 2012 manual, that statement has been omitted.

Ps One last question. Ever heard of anyone smelling burning oil for an extended time after their first oil change, even though no oil was spilled?
 
Hib.

Any word from your friend at Gm on the extra half quart question?
 
Is the oil filter on tight....? That happened to me once.....

Oil filter is tight.
From what I have read, it seems to be pretty common with the C6 to have the oil burning smell after an oil change. No one seems to know why.
 
Oil filter is tight.
From what I have read, it seems to be pretty common with the C6 to have the oil burning smell after an oil change. No one seems to know why.


I changed the oil in my '12 back in April and did not notice and odor of oil burning.

Where are you finding the information that says it's a common problem?
 
I changed the oil in my '12 back in April and did not notice and odor of oil burning.

Where are you finding the information that says it's a common problem?

Hib.
Do a Google search for: oil smell + C6 Corvette
 
Hi Hib.

Any word from your friend at GM?
Happy Holidays!
 
Hi Hib.

Any word from your friend at GM?
Happy Holidays!

Yeah, he got back to me. I just forgot to post it.

He said:
If the car has Z51 it has an oil cooler. Cars without the oil cooler, will show extra oil when adding 6 qts. We didn't distinguish different oil quantity between the 2 cars.

So in other words: prior to when there was a dry sump version of the LS3, there was web sump with cooler (6qts) and without cooler (5.5qts), but service data said 6-qts for both and still says 6-qts even thought the wet-sump with cooler configuration is no longer available and, thus....all LS3 wet sumps are now 5.5qts.

Hope that helps.
 
Yeah, he got back to me. I just forgot to post it.

He said:

So in other words: prior to when there was a dry sump version of the LS3, there was web sump with cooler (6qts) and without cooler (5.5qts), but service data said 6-qts for both and still says 6-qts even thought the wet-sump with cooler configuration is no longer available and, thus....all LS3 wet sumps are now 5.5qts.

Hope that helps.

Hi Hib.

Thats exactly what I was looking for. My 12 GS convertible has a wet sump and no oil cooler, so I will add 5.5 quarts when I change my oil and filter from this point forward. That should put the oil level shown on my dip stick right at full when checking the oil level when cold.
 

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