jiperri

I have a 2016 C7 and had the oil changed recently and now I can detect an oil smell inside the car when driving. I had the dealer check and the dipstick shows it was a quarter inch over the full mark. My service guy said that was not a problem but it does make me wonder if it is in fact overfilled. Can anyone shed any light on this. Thanks for your help.

NSC5

If it is only 1/4" over that isn't enough to cause any issue. My 2016 Z06 always has a slight oil smell for the first 100 miles or so after a change and the oil level is kept between the add and full marks. At the first change I suspected the dealer of either overfilling or spilling some oil but neither was the case and I get the same initial smell after I have changed it and I know that none was spilled and the fill level is correct. It dissipates soon after the change.

My first Duramax diesel had this same oil aroma issue after a change and for it I changed from the Rotella I had used for prior diesel engines to Delo 400 because the Rotella truly stank after an oil change.

dbaker

Discussed many times about the dry sump.

Do a search and lot's of info will come up.

One of the reasons many of us tell the tech to only put 9qts in and give you the 10th....to avoid overfill.

\db2

jiperri

Thanks for the reply. I am taking it back to the dealer to have him check it out.

NSC5

Grossly overfilled would be an issue but 1/4" isn't.

A couple of notes if it is a dry sump:

1.Make sure the dealer checks it at the proper time after engine shutdown. IF they wait too long the oil in the storage tank will start to drain back to to the sump and the service tech will read an actual high level as either normal or low depending upon how much time passes between engine shutdown and checking. This is a too common mistake made both by owners and dealer personnel.

2. With the dry sump GM recommends for track usage that the oil be kept at about 1/2 quart above the full line so a slight overfill definitely causes no damage with the dry sump system. With a wet sump it should not be above the full line. If either system is grossly overfilled then oil will go where it should not and this problem most commonly occurs with a service person who doesn't understand the procedure for the dry sump system and either neglects to pull both drain plugs during an oil change or takes a reading after the engine has been sitting for awhile and then overfills it because of a false low reading.

383vett

The tech probably didn't wipe the pan area where oil dripped after draining from the plugs. The oil would be thrown up onto the pipes and it would smell like burnt oil for a while. As stated earlier, that is one reason some of us prefer to do our own oil changes.

Bill Dearborn

Do you have a Dry Sump car? Base Stingray comes with a Wet Sump and the rules for it are different than they are for the Dry Sump cars. Dry Sump car has a reservoir at the rear of the engine compartment on the passenger side and the dip stick is located in the reservoir. To properly check oil level the OIL Temperature (NOT Coolant Temperature) has to be above 175 degrees before the engine is turned off. Then you must wait 5 minutes but no longer than 10 minutes to check the oil level. Drivers running on track are told to over fill the dry sump by a half quart of oil. That adds right around a 1/4 inch.

Doing an Oil Change requires both drain plugs be removed to drain all of the old oil. Removing only one will result in retention of a large quantity of old oil in the system and subsequent over fill. Complete fill of 9.8 quarts will take oil level to the top dot on the dipstick.

Bill

Bill Dearborn

I get the oil smell even when I don't spill any oil when refilling and wipe down the oil pan. Happens with every oil change on both dry sump cars I have owned.

bill

Foosh

I agree 1/4" is likely not a problem, but I like to keep it between the 2 hash marks just to ensure it doesn't burp oil through the dry sump vent lines and into the intake.

Many of us ask that only 9 qts. be added during a dry sump oil change, and for them to provide the last qt. for us to adjust the level later. My experience, over 4 oil changes, is that with only 9, the level is half-way between the 2 dipstick marks. That's likely because most dealers can't make money on an oil change by letting it drain for an extended period, and it's impossible to get all the old oil out.

The new '18 I took delivery of a couple of days ago, was just a hair over the full mark from the factory. At the 500 mile change in a couple of weeks, I'll go back to my system of only adding 9 qts, and adjust if necessary.

JumpingJackFlash

Bill, I believe I read in the owners manual to bring the oil level up to 1/8 inch below the top mark...no more.

Gearhead Jim

The manual on our 2017 says that dry sump engines should be kept at or near the .5 qt overfill point for track driving, which is about 1/4" above the Full mark.

JumpingJackFlash

Gearhead Jim

My point was that minor overfilling is not a problem on the dry sump C7, just like it wasn't on our wet sump C5 and C6, and our 2017 manual does not say anything about deliberately filling 1/8" short for either system, street or track.

The recommendation for street use is "at or near" the full mark.
Sometimes they make changes in the manual just to confuse people.

Foosh

Actually, the recommendation for street use is anywhere between the upper and lower marks.

JumpingJackFlash

Foosh

Yes, the new '18 built 1/18/18, that I took delivery of a few days ago is about 1/8" above the top mark.

JumpingJackFlash

4thC4at60

You're worried about 1/4 of an inch? Really?

Dude.... go drive the car.....

I don't understand why people treat these things as if they're a delicate piece of art or glass... I don't mean abuse them, but they're cars.

JumpingJackFlash

Foosh

Yes, I had a dry sump C6 Z06, as well as a dry sump '14 Z51. I always check it 3 times at 7,8, & 9 minutes after shutdown with the oil temp above 175º.