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No oil in 2007 Impala

My husband checked my oil and the dipstick was bone dry. I took it to the dealership; they immediately gave me a loaner car, and fortunately I still have 2 months left on the GM engine/power train warranty. The last oil change was only 4,000 miles ago. My questions: Why didn’t any warning lights go on? Why does the indicator show that there is 32% oil remaining? Where did the oil go? The dealership is open only for 1/2 day (Saturday) and I may not get an answer from them until Monday.

That indicator does not mean there is 32% of the oil remaining. It means that theoretically there is 32% of the oil life remaining.

All car owners must get in the habit of checking the oil level every couple of weeks or so. Failure to do so is neglect on the part of the car owner.

As to why your car is using oil more info needs to be provided about mileage on the car and so on. It could be due to extended oil changes which are causing piston ring problems.

You say you took it to a GM dealership. Does this mean towed or driven and if driven does this mean AFTER adding oil to it?

The good news is that your warranty is still in effect.

The bad news is that your Owner’s Manual undoubtedly contains some text along the lines of…you should check the oil dipstick at every fuel stop. Because verbiage to that effect is contained in the Owner’s Manual, a car manufacturer can refuse warranty coverage on the basis of owner negligence–in this case, neglecting to check the oil as recommended.

No, most of us are not obsessive enough to check the oil every time that we gas-up the car, but anyone who expects their car to last for the long-term should check his/her oil dipstick at least every few weeks. In other words, the crankcase did not go from “full” to almost-dry overnight. This process could have taken anywhere from a few weeks to a few months (depending on the actual condition of the engine), and checking the dipstick at least a couple of times a month could most likely have avoided this situation.

As to warning lights, unless your car has a warning light for low oil level (some do, some don’t) then you would not see a warning light until the oil level fell so low that there was almost no oil pressure, and at that point, the oil pressure warning light would start glowing. There is a difference between oil level and oil pressure, and your engine can have acceptable oil pressure until the point where the oil level falls very low. You should check your Owner’s Manual for details of whether your car has a low oil level warning light. It definitely has a low oil pressure warning light.

And, regarding “32% oil remaining”, that indicator is telling you that you are not yet ready for an oil change. That indicator has absolutely nothing to do with how much oil is remaining in your crankcase, and someone could be running with an almost dry crankcase while the electronic systems on your car are assuming that the crankcase is full, and are basing the oil change interval on a full crankcase and ideal driving conditions.

Without trying to sound too pedantic, I REALLY think that you need to read the section in your Owner’s Manual regarding the warning lights and other indicators on your instrument panel. Your situation is a perfect illustration of how assuming that you know what an indicator means can be…expensively wrong.

The oil either leaked out (loose oil drain plug, double-gasketed oil filter, leaking gasket are the possibilities there), or was “burned” (consumed) by the engine. You did not tell us how many miles are on the odometer, but it is possible for a 5 year old engine to burn oil, especially if it has been subjected to long oil change intervals, has chronically been run with a low oil level, or if the PCV valve is stuck.

Please post back with details regarding what the service department told you, as well as the current odometer mileage, and the car’s maintenance history. Those oil change interval indicators can lead car owners to go…perhaps as long as…10,000-12,000 miles between oil changes, and unfortunately, that is just not realistic for most driving situations. Most of us in this forum believe in changing oil every 5k-6k miles, and some (me included), do it every 4k miles, because oil is much cheaper than engines are.

Also–bear in mind that cars which are driven in mostly local driving need to have their oil changed on the basis of elapsed time, rather than on odometer mileage, so if…let’s say…it takes you six months to drive 5,000 miles, then you should be changing the oil every six months. So, please tell us also how many months you normally go between oil changes, as this information is definitely relevant to your situation.

BarbR–On re-reading your post, I have to make another comment.
Before I make that comment, please bear in mind that I am not trying to “beat you up” regarding the car’s problems, but merely to try to educate you in order to avoid a repeat incident with your next car.

Anyway, regarding, “Why does the indicator show that there is 32% oil remaining?”…let us just assume for the moment that this indicator had something to do with the amount of oil in the crankcase. (Which it does not.) While you can safely drive your car with less than 1/3 of a full tank of gas, it is absolutely not safe for your engine to operate it with less than 1/3 of the required amount of oil.

Think of gasoline as being equivalent to your food supply, and think of oil as being equvalent to your blood. You could definitely survive for an extended period of time with 2/3 less food, but you could not survive with 2/3 less blood than your circulatory system is supposed to contain.

Similarly, an engine which is run for hundreds–or perhaps thousands–of miles with a low oil level is going to experience wear that is many times greater than it would normally experience in the same number of miles if it was operated with the correct level of oil. The end result of this very high engine wear is…increased oil consumption, and…eventually an early demise for an engine that could have run for many more years.

I won’t get into the technical reasons for trying to keep the crankcase full or almost full at all times, but suffice it to say that the goal is to not allow the oil level in the engine to fall more than 1 qt below the full mark at any time. Personally, I replenish my motor oil as soon as I see that it has fallen by 1/2 qt. Of course, this is accomplished by checking the oil level on a regular basis.

Please respond with details regarding the number of miles on the car’s odometer, how often you typically change the oil (in terms of both miles and elapsed time), the type of driving conditions in which this car is typically used, and exactly what the service department told you.

As update No. 1, my car has approx. 72,400 miles. I do have the oil changed about every 5,000-6,000 miles. I retired in December so I’m not commuting every day (48 miles round trip). The last oil change was in November, at 68,500 miles. Thank you for your comments and re-educating me: I now understand the “oil life remaining” part. However, my service tech told me at one time that it’s OK to rely on this indicator as to when to change the oil and that I could wait until it’s below 20%. I was even turned away one time because it didn’t need to be changed yet! I will certainly check the dipstick more often, especially now that I’m not driving as much. I will post another update next week when I know more…thanks again.

It’s also possible that the oil pressure sending unit is cracked which could allow the engine oil to leak out very rapidly.

Are you sure the car is still under warranty? I’m not familiar with current GM warranty periods but I thought it was 5 years/100k miles on the drivetrain?

Your car is a 2007 model and it was first put into service (meaning sold to a customer or put into use as a dealer demostrator) in April of '07 or prior to that date the warranty has lapsed due to time, not miles.
Many 2007 model cars are sold in 2006 or at the first of 2007 so you need to consider the date the car went into service; no matter if you bought it new or as a dealer demo.

Changing oil every 5-6k miles may not be good enough. If your driving is predominantly short hop, stop and go, and especially depending on environmental conditions, it could be that type of driving has created problems with the oil control rings on the pistons.

Keep in mind that driving around with the crankcase low on oil just exacerbates the above problem with piston rings.

With all the controls in place either your oil pressure did not drop enough to set off a warning light, or the warning light failed. If your oil pressure did not drop enough to set of the light you are golden, If your oil light did not go on then the engine is toast, hopefully the warranty covers it.

“If your oil pressure did not drop enough to set of the light you are golden”

Not necessarily.
If this car has been run for an extended period of time with a low oil level, there will be consequences.
If a full crankcase on this car calls for…let’s say…5 qts, once it is down to 4 qts, the oil is going to be running hotter than it would be with 5 qts. This leads to viscosity breakdown. The rate of oil consumption then increases geometrically, and soon, that 4 qts is down to 3 qts.

Once the engine is running on only 3 qts, the condition of that oil deteriorates very rapidly, leading to probable coking of the piston rings. As the oil level gets lower and more contaminated as a result of the high concentration of blow-by, the oil pickup screen has a higher probability of becoming clogged with sludge, and the very small caliber oil galleries also have a high probability of becoming clogged with oil sludge. The net effect of that sludge can be oil starvation to bearings and other lubrication-sensitive areas of the engine.

In this case, with no oil registering on the dipstick, I think it is likely that the oil level had dropped to less than 3 qts, and at that point, all bets are off regarding the longevity of this engine–even if the oil pressure warning light never came on.

So–I disagree that the OP is “golden” if the oil pressure never dropped low enough to turn on the oil pressure warning light. There can be a whole lot of damage before that light turns on, but once it does start glowing, it will signal “Game Over” very rapidly.

VDC we have been on the same page so many times. Sure I hear what you say, and do not disagree with what you say, but in this instance I am basing it on personal experience, If I am wrong I apologize to the OP.

Just because no oil showed on the dipstick does not mean the engine ran out of oil or that any damage was done…It just means the oil level was below the end of the dipstick…This is not a warranty issue. This is a not checking the oil issue…One quart of oil every 1000 miles is NOT considered excessive oil consumption. You need to get in the habit of checking your oil every other fill-up and keeping it topped up…

Oil pressure lights normally turn off at 3-5 PSI of pressure. That kind of pressure may kill a light but it’s not good for protecting an engine and 3-5 PSI could be oil alone or a combination of oil and inhaled air.
Pressure that low will exist near the pump and sending unit; not necessarily further along the line in places like the far end of the crankshaft or upper end with oil being lost along the way and pressure being even lower than that.

When I see a shoving match going on between 3-5 PSI of oil pressure on one side of a bearing in a running engine and 1500-1800 PSI on the other side of that bearing then the 800 pound gorilla is probably going to win.

The car makers have a vested interest in considering oil consumption normal; to admit a problem would cost them countless billions of dollars in engine warranty claims or possibly having to buy back countless vehicles.

BarbR, Monday sometime, the dealership is going to call you and tell you to come get your car and to check the oil more often. End of story…

If neither you or your husband check the oil very frequently, there is always the possibility that the last time you had your oil changed they didn’t fill it all the way. It wouldn’t be surprising if you made the natural assumption that it was filled properly and didn’t bother to check the oil level right after the last oil change. It might be difficult to prove they shorted you unless you checked immediately after, however. You’ll have to monitor your oil level more closely from now on to see if you actually have high oil consumption or was this a one time deal. If your actual oil consumption turns out to be moderate, not filling it with the proper number of quarts could be an explanation of why you were so low this time. Just a thought.

For all the reasons stated above, I agree that driving with an oil level below the dipstick is definitely flirting with trouble. Without knowing how much oil an engine has, damage “can” happen in a heartbeat.

However, given your oil light did not illuminate, I agree with Caddyman’s above comment. The years I worked in garages, I saw many customers come in with the oil level below their dipstick. We’d fill the oil and send them on their way - with no ill effects.

Opinions differ on how much damage will occur (and how quickly) when the oil level range is between “just below the dipstick” and “not at the point where the pump begins sucking air”. But I think we all agree “don’t go there.”

I’m in agreement that the dealer would likely proclaim the engine good and send them on their way; with one exception.

The car is 5-6 years old and apparently the owners did not know up to the time of this posting that the OLM does not track oil level and never raised the hood to check it.
This would bring up the following questions in my mind.

Were there any symptoms such as knocking, rattling, or whatever that suddenly led to this newfound desire to raise the hood and check the oil? Why did hubby decide to check the oil after this lengthy period of ownership?

Regardless of who is right, I would think the remaining oil should be drained. One to see how much was left, and two to pull a sample to have an analysis done to check for metal particles. Then you’ll have a better indication of damage done or not. Well worth the $30 for piece of mind.

“I would think the remaining oil should be drained.”

That is definitely a good idea, and the OP should visit the dealership at opening time tomorrow to make this request, and to offer to pay for the oil analysis.
However, it may be too late for that plan at this point.

There was an oil leak. Front cover gasket and seal were replaced. All covered under original power train warranty. I was also given a brand new Impala with 68 miles on it as a loaner! I paid for an oil change. Thank you all for your input.

In addition, I was told the car was down 2 1/4 qts. oil, with 2 1/2 qts. still in the car. No metal fragments were found.