The dreaded oil stink after an oil change
05-21-2013, 12:58 PM
#41
Mine shows 1/2-qt. overfilled on the dipstick with six quarts installed. My dealer used six quarts for my first free oil change and I drained out 1/2 qt. the next day, which now shows just a tad over the full mark. In the future I'll use 5½ quarts for oil changes.
The manual says to use six quarts yet warns you of catastrophic engine destruction if you run it over the full mark, and I exaggerate only mildly. One of those two specs in the manual are wrong, and I suspect that using six quarts and showing ½-qt. overfill won't hurt anything. I would bet the crank isn't making contact with the oil in the sump at that point, and IMO that's the only danger of running a high oil level.
The manual says to use six quarts yet warns you of catastrophic engine destruction if you run it over the full mark, and I exaggerate only mildly. One of those two specs in the manual are wrong, and I suspect that using six quarts and showing ½-qt. overfill won't hurt anything. I would bet the crank isn't making contact with the oil in the sump at that point, and IMO that's the only danger of running a high oil level.
05-21-2013, 01:00 PM
#42
this does not happen to every car, and is more often to happen in a 11 or 12. GM knows its the lube that is used on the rear main seal. The more lube used the more the smell when the oil is changed. Its not caused by spilled oil or over fill this odor is a result of a chemical reaction between the oil and the lube on the seal. Yes I use Mobil 1. and the oil changes have been done at a dealer so far. Time will tell what happens and I will update as I get new information.
05-21-2013, 01:00 PM
#43
Melting Slicks
None of this rear-seal, new-oil explanation makes any sense to me. I'm not saying it doesn't happen, as I've seen stranger phenomena than this in the realm of cars and motorcycles, but it's just really bizarre.
05-21-2013, 01:04 PM
#44
Melting Slicks
The spec to keep it at or below the full mark takes that into consideration, I'm sure, and they warn you in no uncertain terms not to overfill. All that said, I agree with you that there is likely no danger here. I'll still use 5½ qts. in the interest of caution, as it won't affect anything.
05-21-2013, 01:20 PM
#45
Race Director
Our 2011 GS A6 auto did it a couple of times when it was still very new. Now, as the miles start to add up, we haven't had that happen anymore. We are at 44,000 miles now.
05-21-2013, 02:53 PM
#46
Team Owner
05-21-2013, 02:58 PM
#47
Drifting
X2 Seems odd that some cars do this and others don't when they are all made on the same assembly line with the same sealants and engine components. There doesen't seem to be a common link except for the oil change itself.
05-21-2013, 07:09 PM
#48
Burning Brakes
There is a looooong post about this issue. I discovered that my 2012 GS A6 had that smell after I did my first oil change. When I checked, I was over full on the stick, following the owners manual. It says the Grand Sports hold 6 qts. Wrong. Unless you have the upgraded oil cooler, your car holds 5.5 qts. I had to drive the car a couple of days like that, had the smell, really pissed me off. Got a chance to put it back up on the ramps and pulled out .5 qt. smell went away.
I read all this stuff about assembly lube on the rear main seal, doesn't make any sense to me IMHO. Believe what you will, but try 1/2 qt less than what Daddy GM says and see if you have the problem. This s for the wet sump guys. Dry sump might be the same, but decide for yourself.
I read all this stuff about assembly lube on the rear main seal, doesn't make any sense to me IMHO. Believe what you will, but try 1/2 qt less than what Daddy GM says and see if you have the problem. This s for the wet sump guys. Dry sump might be the same, but decide for yourself.
06-05-2013, 09:42 AM
#51
Safety Car
If was oil dripping on a hot surface it would burn off quickly. The oil smell people have been talking about lasts for weeks or months. In my case it lasted about six weeks and faded gradually during mostly city driving, but then resurfaced briefly after a 35-mile trip on the highway to the dealer last week. The tech, who is highly touted in the local Corvette community, said he thinks it is oil falling on the cat, and that they've had some complaints about it. He hadn't heard of the rear-seal idea, but agreed it would burn off quickly if it made contact with a hot exhaust component. Beyond that he didn't know, and apparently GM hasn't sent them any info about it since the service writer didn't have a clue either. Both thought the rear-seal idea was improbable.
Several weeks ago when I was smelling it at every stop after the engine was at operating temperature I stopped the car and sniffed around. I didn't make a show of it, as sniffing around a car would undoubtedly look weird. Indeed, I find this entire issue weird. I couldn't smell it at the rear of the car (exhaust) or in the engine compartment, but did inside the car when the vent was not set to recirculate. It must be getting in at the vent intake, but if it's in that area why can't I smell it under the hood?
Anyway, I haven't noticed it since that trip, so maybe it's gone for this oil change. BTW, I used the GM Dexos blend for this change (free from the dealer), so we can't pin it on Mobil 1, which I'll be switching to for the next oil change.
Mine's a base coupe (wet sump) and I have it.
Several weeks ago when I was smelling it at every stop after the engine was at operating temperature I stopped the car and sniffed around. I didn't make a show of it, as sniffing around a car would undoubtedly look weird. Indeed, I find this entire issue weird. I couldn't smell it at the rear of the car (exhaust) or in the engine compartment, but did inside the car when the vent was not set to recirculate. It must be getting in at the vent intake, but if it's in that area why can't I smell it under the hood?
Anyway, I haven't noticed it since that trip, so maybe it's gone for this oil change. BTW, I used the GM Dexos blend for this change (free from the dealer), so we can't pin it on Mobil 1, which I'll be switching to for the next oil change.
Mine's a base coupe (wet sump) and I have it.
I change my own oil and the weird part is that mine didn't start smelling until the middle of an oil change; I think that throws the spilled oil excuse out the window on my car at least.
06-05-2013, 02:44 PM
#52
Advanced
I had the same problem after my first oil change (GS A6). The dealer did the change (free) and as soon as I got the car back the smell was very obvious mostly coming from the driver's side air vents. I read all the discussions on this blog regarding the problem and searched for a solution. The smell of burning oil has to be caused by oil contacting a hot surface but the smell did not seem to be going away after a number of weeks of driving the car. So I put the car on a lift at a friends garage and started looking. At first pass there did not seem to be any oil stain on the pan around the oil filter. However, when you got up close to the pan with a shop light a stain became fainlty visible on the pan. We ensured the filter was tight (it was) and then proceeded to clean the pan around the filter by just spraying it with brake cleaner. The stain cleared up and low and behold the smell went away.
Two important observations (IMO) the oil filter is surounded by nearly half its circumference by the pan - meaning there is virtually no way to change the oil filter without spilling oil on the pan. When oil contacts the pan (and assuming you wipe it off) it still leaves a stain (meaning residual oil) that is very difficult to actually see.
I do not know if M6's are different than the Auto's or the dry sumps. I do know it solved my problem.
Hope this helps.
Two important observations (IMO) the oil filter is surounded by nearly half its circumference by the pan - meaning there is virtually no way to change the oil filter without spilling oil on the pan. When oil contacts the pan (and assuming you wipe it off) it still leaves a stain (meaning residual oil) that is very difficult to actually see.
I do not know if M6's are different than the Auto's or the dry sumps. I do know it solved my problem.
Hope this helps.
Last edited by Mchapman; 06-05-2013 at 02:46 PM.