Excessive oil usage on a 2013 XTX AWD 3.6 SIDI V6 VVT

[cygnusx1r]

I have a 2013 with 43000 on the engine that is using 2 quarts between oil changes or about 6500 miles and the dealer says that it is normal for this to happen but it just started within the last 15000 miles and has never happened in the past. It has been looked over three times by the dealer and they can’t find that it is leaking anywhere and are trying to add different additives to it to stop the consumption.

I’ve had numerous makes of cars in the past and this is the worst oil consumer that I have ever had and really can’t believe that a 60,000 car should be using that much oil. Any help will be greatly appreciated.

[cdgrinci]

Although 2,000 miles/quart of oil is pretty much the industry standard as being normal, this is rarely the case (or normal in my book either). Assuming it isn't leaking (out), it is probably being burned; from whence is the question, and that usually means passing by the rings or valves. If you don't exercise the engine much and/or don't use toptier gasoline, you may have sticky rings. This might respond to some enthusiastic throttling with a good gasoline additive (I'm thinking Techron or Seafoam) added to the gasoline. If it is the rings then some high(er) rpms may make it respond to treatment.

[Bruce Nunnally]

i am sorry you are experiencing this issue.

Has the dealer done an oil consumption survey where you bring the car back in 500 mile increments and they measure oil level? What was the result?

Can you describe more details on this? "...and are trying to add different additives to it to stop the consumption."

That does not appear to be what the shop guides tell them to do.

Are you concerned the oil usage is a sign of engine mechanical issue? It may not be, it may be normal for broken-in engine, although it is possible that you have an issue. Sounds as if Dealer feels it is within normal specs.

What do you want to happen? If they remove & replace engine you may be at same place down the road. If they rebuild engine there is some risk you will be worse off as a result.

I might ask for an extended warrenty on powetrain but your powertrain warranty is already 75k/6 years right? That gives you time to see how engine does for the next 30k miles?

[winterset]

Are you checking and filling it when it is warm (but not running) if you are checking it ice cold, and filling to the line, then you are most likely over filling it, and the excess oil of blowing into the air oil breather, and getting buned in the intake. Keep the oil level on the low end of full, perform a WOT or 2, and you should be fine in a few hundred miles.

[Cadillac Jim]

I once knew someone who thought that his Chevy Suburban was burning oil, but he found that the dealer wasn't topping it off when he had it changed.

I don't know what the current policy is with your engine. When I did keep track of such things a decade or so ago, the standard was that a dealer would look at the problem if oil consumption was 2000 miles a quart or worse, and 1000 miles a quart or worse mean new rings or whatever it took to fix it. I suspect that this is still the warranty terms.

Ask your dealer what your warranty is, and ask them to print it out for you and read it yourself. Have your reading glasses with you.

Beware the dealer trying different additives. You can stop oil burning on anything with enough STP or Motor Honey or some such but this is really bad for your motor and costs you performance and fuel economy. And it can void your powertrain warranty.

[Z15]

The accepted rate of oil consumption for engines used in the vehicles referenced is 0.946 liter (1 qt) in 3200 km (2000 mi).

Important: This rate only applies to personal use vehicles, under warranty, that are driven in a non-aggressive manner and maintained in accordance with the appropriate maintenance schedule, with less than 58,000 km (36,000 mi), or driven at legal speeds in an unloaded (for trucks) condition.

Important: This rate does not apply to vehicles that are driven in an aggressive manner, at high RPM, high speeds, or in a loaded condition (for trucks). Oil consumption for vehicles driven under these conditions will be more.

Many factors can affect a customer's concern with oil consumption. Driving habits and vehicle maintenance vary from owner to owner. Thoroughly evaluate each case before deciding whether the vehicle in question has abnormal engine oil consumption.

Gasket and External Leaks
Inspect the oil pan and engine covers for leakage due to over-tightened, damaged, or out of place gaskets. Inspect oil lines and fittings for signs of leakage.

Improper Reading of the Oil Level Indicator (Dipstick)
Verify that the dipstick tube is fully seated in the block. When checking the oil level, make sure the dipstick is wiped clean before taking an oil level reading and fully depress the dipstick until the shoulder bottoms out on the dipstick tube. The dipstick should be the proper part number for the engine/vehicle that is being checked.

Notice: Operating your vehicle with an oil level that is below the minimum level indicated on the engine oil dipstick can result in severe engine damage. Repairs resulting from operating an engine with insufficient oil are not covered under the terms of the New Vehicle Warranty.

Important: Refer to Owner Manual in SI for checking and adding engine oil.

Not Waiting Long Enough After Running Engine to Check Oil Level
Some engines require more time than others for the oil to drain back into the crankcase. To assure a sufficient amount of oil has drained back to the crankcase, and an accurate reading can be obtained, the vehicle should be allowed to sit for at least 15 minutes, after the engine has been shut off, before taking an oil level reading. In order to ensure accurate results, the temperature of the oil should be close to the same temperature as the last time the oil level was checked.

Important: This does not apply to 2006-2009 Corvette Z06 equipped with the 7.0L LS7 and the 2009 Corvette ZR-1 with the 6.2L LS9 engines (dry sump). Follow the instructions in the Owner Manual for checking the oil in this application.

Improper Oil Fill After an Oil Change
Following an oil change, verify that the proper amount and type of oil was put in the engine and that the oil level on the dipstick is not above the full mark or below the add marks. Refer to the Owner Manual or Service Manual for information on recommended oil quantity, viscosity, and quality.

Aggressive Driving, High Speed or High RPM Driving
Aggressive driving and/or continuous driving at high speeds/high RPMs will increase oil consumption. Because this may not always be an everyday occurrence, it is hard to determine exactly how much the oil economy will be affected.

A higher rate of oil consumption is normal for vehicles equipped with manual transmissions that are driven aggressively. By "aggressive," we mean operation at high RPM (3,000 RPM to redline), with frequent use of engine braking (using the engine to slow the vehicle). Vehicles that are driven aggressively may consume engine oil at a rate of up to 0.946 L (1 quart) every 805 km (500 mi). This is normal for a vehicle that is driven aggressively. No repair is necessary. This characteristic does, however, require the owner to check the engine oil level at sufficiently frequent intervals, especially when driving aggressively, to assure the oil level remains within the recommended operating range. As the Owner’s Manual recommends, you should check the oil level every time you get fuel.

Towing or Heavy Usage
Towing a trailer will increase oil consumption and may cause oil consumption to fall below the normal accepted rate referenced in this bulletin for an unloaded vehicle in a personal use application. Large frontal area trailers will further increase the work required from the engine, especially at highway speeds, and thus increases the rate of oil consumption.

Crankcase Ventilation System
Verify that the positive crankcase ventilation (PCV) system is operating properly. Blockages, restrictions, or damage to the PCV system can result in increased oil use.

Oil Dilution (Fuel and Water)
On vehicles that are usually driven short distances, less than 8 km (5 mi), especially in colder weather, unburned fuel and condensation generated from cold engine operation may not get hot enough to evaporate out of the oil. When this occurs, the dipstick may indicate that the oil level is over-full. Subsequent driving on a trip of sufficient length to enable normal engine operating temperature for 30 minutes or more, in order to vaporize excess moisture and fuel, may give the customer the impression of excessive oil consumption.

Engine Temperature
If an engine is run at overheated temperatures (see Owner's Manual or Service Manual) for more than brief periods, oil will oxidize at a faster than normal rate. In addition, gaskets may distort, piston rings may stick, and excessive wear may result. Verify that all cooling system components are in proper working order.

Engine Wear
Piston scuffing, excessive piston-to-wall clearance, tapered or out of round cylinders, worn, damaged or improperly installed valve guides, seals and piston rings will all cause an increase in oil consumption.

[Cadillac Jim]

If I'm not mistake, most of Z15's post is a quote from a factory shop manual. It covers all the common problems that can cause real or phantom (apparent, but not real) oil consumption.

[winterset]

Imo, the most important, and road proven statement is missing. Driving a N* in stop and go at low speeds wirhout opening it up every once in a while causes carbon deposits to form on the piston rings. This is the 2nd most contributing factor to oil consumption. Thus why i suggested a WOT. The mechanics know this, but no one will every find a document from GM requseting a customer to put their car on 3rd gear, tear a$$ on the highway to 75, then release the throttle till you get to 40, then repeat 4 times. The only solution they had was pouring that solution down the spark plug holes, letting it sit, and suckng it out, and hopeing it dislved the carbon.

[Cadillac Jim]

A substitute for a WOT treatment is a road trip, about 250 miles each way, on a tank of top-tier gas, 91 octane or higher.

I once solved a similar oil-burning problem by getting my oil changes at a service station instead of the dealer. They had done the kerosine-in-the-plug-holes treatment with no effect whatsoever. It was burning about a quart every 500 miles. The first oil change elsewhere instantly went down to a quart every 1000+ miles, and after that it got 2000+ miles to a quart and continued to improve.