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2007 Lucerne Oil consumption

Newer car designs, the engineers focus on mpg to meet the required EPA fleet-specs, so they try to get all the moving parts need to move with less friction, which requires the use of thinner oils and can contribute to higher oil usage than older cars. Some manufactures claim oil usage of one quart in 1000 miles is normal for their cars.

I am not so sure that the oil consumption, if it truly is 4500 miles/quart will increase dramatically over time. Back in 1982 my brother bought a 1977 Cadillac DeVille at a great price. It used a,quart of oil every 950 miles. He put almost 200,000 miles on the car on top of what was on the odometer. When he sold the car, it hadn’t increased–it still used a,quart every 950 miles. If the OP uses the viscosity recommended for the engine, changes the oil at the specified time or mileage interval and checks the oil at least every other week the Buick should last a,long time

Lots of things to digest here. I know the history of the car. Little old Lady, hardly drove it all. I’ve had great luck with it so far. I’m not going to jump to any rash conclusions. I plan on checking the oil for the next cycle and see if this continues.

The car was given a clean bill of health by the dealer when I bought it… Maybe this isn’t any big deal. Does anyone know of known issues with this engine and oil use?

@jr4488
"Maybe this isn’t any big deal. Does anyone know of known issues with this engine and oil use?"

None, I’ve heard of and I have 3 GM cars with 3800 engines, the newest being an 06 Pontiac. They are good engines and that’s why I have three.

If this was one of my cars, I’d be sure to take a longer trip, 25-30 miles+ at least once or twice per week if not more often. This will help dry things out and keep the exhaust system healthier.

I wouldn’t worry about it. If You like the car and give it some exercise it should continue to be reliable and enjoyable for a long time, yet. If it consumes a half quart or quart of oil in 4,500 miles it is normal and not a concern for you.

Keep the car, drive it, and enjoy it.

CSA

I do have one concern about this car and that is the tires. With only 17,000 miles, these may well be the original tires and the tires may have been manufactured 10 years ago. Even though tires have good tread, aging weakens the tires. I would replace the tires if the tires are the original ones that came with the car. To me, this is a much bigger issue than using a,quart of oil in 4500 miles.
I have purchased quite a,few used cars. With some of the bargain basement cars, the question wasn’t whether or not the car uses oil, but how much oil did the car use. My first car, a,1947 Pontiac used a,quart of oil every 250-300 miles. I paid $75 for the car. However, I did put on good tires. The tires on the car had good tread, but the sidewalls were checked.

As to the car and engine, it’s not necessarily the type of engine that can be affected. ANY engine can be affected by the oil change regimen.

As to the dealer giving the car a clean bill of health that may or may not mean anything. Many dealers put clean cars out on the lot for sale and they know little to nothing about them. They take the car in trade or buy it at auction, send it to the detail shop for cleanup, and out to the lot it goes for sale.

A quart of oil in 4500 miles on an 8 year old car, regardless of the mileage, ain’t nothin’. To me, that’s the bottom line here.

All cars, whether brand new or old and trusted, should receive an occasional look-see at all the fluid levels. Once a week is prudent. Perhaps once every two weeks if it isn’t driven much. That way, if a problem does begin to develop, it can be caught and corrected while it’s still small.

Another practice I like is to simply look around under the hood. You’ll be surprised at what you can see, especially once you become familiar with what’s normal. Years ago on a well-worn pickup of mine I took a look-see and noticed a crusty green area on the radiator. Knowing what it was, copper oxide, I found a new radiator for a cheap price, picked it up, and changed the radiator. After removing it, I pressed the green crusty area with my finger and lo-and-behold, it went right through. The radiator was ready to fail. I just might have saved my engine by catching it before it failed.

"The car was given a clean bill of health by the dealer when I bought it."

Yup!
Car salesmen are known for being scrupulously honest and for never making false statements regarding the used vehicles that they are selling.

Not!

I have owned a variety of vehicles over the years and none of them ever used more than a quart of oil between oil changes except for my Corvair Spyder. I believe that’s normal for most cars and trucks.

The question to my mind isn’t “is it normal”. The question to my mind is “is it indicative of a problem”. IMHO, absolutely not.

The debate on its normalcy is a different debate. I would argue that it is, but whether I’m in the minority or not is irrelevant to whether it’s indicating a problem with the OP’s car.

Almost every car manual now says that oil consumption of one quart per 1000 miles is considered normal. This is clearly a CYA clause. A 0W20 synthetic oil is very thin and some oil consumption should not be surprising.

VDC Drvier, it was not purchased from the dealer. Private party. I had the dealer’s shop do an inspection before purchasing. They serviced it prior to my purchase, they knew the history as did I. Bought from a friend’s Aunt. I dotted all my “i’s” and crossed all my “t’s” on this car. This oil use is a new issue after we have put 13,000 miles and 12 months on this car.

So the bottom line… what might be the cause of oil consumption? Once I know what to look for, I can

a) see if there is indeed a problem b) service the cause if needed.

As I said before, I am not comfortable with it using oil as a normal part of daily use. If it can be repaired and stop using oil that would be my preference. It is a nice car. We like the comfort, ride, etc.

“what might be the cause of oil consumption?”

IMHO this level of consumption is not ideal but within the norm.
Many owners of European luxury cars would love 4500 miles per qt.

Reducing consumption would likely involve first making sure the PCV system (not just the valve) is working properly.
Then, engine disassembly, refinish the cylinder bores and replace the rings and valve stem seals.
Hardly seems worth it, eh?

“Many owners of European luxury cars would love 4500 miles per qt.”

Indeed they would!
We have had a number of posts in this forum from owners of new and nearly-new Audis, reporting/complaining that their car’s engine consumes one qt of oil after less than 1,000 miles of driving. When they have taken their complaints to Audi on the corporate level, they have been told, “Consumption of one qt of oil every 600 miles is within normal limits for our engines”.

I agree with those who have said that the OP is seeing an issue where there really isn’t any–with a modern engine using very “light” oil.

All that the OP can do at this point is to be sure that the oil is changed at least every six months, regardless of how few miles have been driven during that timeframe.

The OP should just check the oil and find something else to worry about. That amount of oil use is not enough to justify spending money on.

@jr4488
A Better, Cheaper Plan To Solve An Oil Consumption “Problem” (That Does Not Exist), Especially On A Car That Does Not Accumulate A Lot Of Miles, Would Be More Frequent Oil Changes!

This way the oil will never get very low and you’ll be doing the engine a big favor, too. If you read the Owner’s Manual they describe Severe Driving maintenance and the need for more frequent oil change intervals. Short trips should be listed there. Check it out.

This whole thing reminds me of a guy on my golf team, who after almost every shot, is upset with himself for not playing better. On a beautiful sunny day, on manicured green grass, birds chirping, he doesn’t appreciate the beauty around him and he focuses on what he’s doing wrong. To tell you the truth, he plays OK (like the rest of us) and doesn’t really have a problem, but I think he doesn’t realize it.

(I should listen to this advice myself, sometimes.)

This sounds like a fantastic car. It is actually behaving like a new car would. Appreciate it. Enjoy it!
CSA

As I said before, I am not comfortable with it using oil as a normal part of daily use.

I don’t mean this to be snarky, but that’s like saying you’re not comfortable with having to clean the kitty litter box twice a week. Cats poop. Engines need oil. Some more than others.

Using a quart of oil in 4500 miles is nowhere near any kind of repairable problem. If over the next 10,000 miles the car uses more than 2 quarts of oil then perhaps it’s time to do an oil usage test and see how much oil is consumed over the next 10,000 miles.

If you must, try replacing the PCV valve inside the intake manifold and make sure the O-ring for the PCV valve is located properly. Other than that, I still believe, in my professional opinion, that there is nothing to repair because there is no problem.

" If it can be repaired and stop using oil that would be my preference."

Yes, it can be repaired. Possibly by replacing the PCV valve, which costs all of…maybe…$4.00.
However, if that doesn’t “fix” the problem, then the only alternative is likely to be disassembling the engine and spending…maybe…a couple thousand $$ on the fix.

Just how much money are you willing to spend on repairing the engine of a 8-9 year old vehicle, especially in view of the relatively meager price of a few qts of oil over the space of several years?

Yes, it can be repaired. Possibly by replacing the PCV valve, which costs all of…maybe…$4.00.
However, if that doesn’t “fix” the problem, then the only alternative is likely to be disassembling the engine and spending…maybe…a couple thousand $$ on the fix.

I’d be willing to bet one of my fresh, just gifted muffins, that a professionally rebuilt engine has about a 50/50 chance of using less than 1 quart in 4,500 miles. That leaves a 50/50 chance of consuming the same amount or more.

I’m pretty sure that if it did use the same amount or slightly more and was returned to the pro that the pro would say, “normal.” :neutral:

If it ain’t broke[n], don’t fix it!
CSA

@jr4488
From 2007 Buick Lucerne Owners Manual Page 4:

“How to Use This Manual
Many people read the owner manual from
beginning to end when they first receive their new
vehicle. If this is done, it can help you learn
about the features and controls for the vehicle.
Pictures and words work together in the
owner manual to explain things.”

From 2007 Buick Lucerne Owners Manual Page 448:

"At Each Fuel Fill
It is important to perform these underhood checks
at each fuel fill.

Engine Oil Level Check
Check the engine oil level and add the proper oil if
necessary. See Engine Oil on page 337 for
further details.

Notice: It is important to check your oil
regularly and keep it at the proper level. Failure
to keep your engine oil at the proper level can
cause damage to your engine not covered by
your warranty.

Engine Coolant Level Check
Check the engine coolant level and add
DEX-COOL® coolant mixture if necessary. See
Engine Coolant on page 347 for further details.

Windshield Washer Fluid Level Check
Check the windshield washer fluid level in
the windshield washer fluid reservoir and add the
proper fluid if necessary."

Also, all of my 3.8L equipped GM cars have in addition to the “low oil pressure warning,” a “low oil level warning” (approximately a quart low).

From 2007 Buick Lucerne Owners Manual Page 225:

“OIL LEVEL LOW ADD OIL
On some vehicles, this message displays when
the vehicle’s engine oil is low. Fill the oil to the
proper level as soon as possible. See Engine
Compartment Overview on page 334 for the engine
oil fill location. Also, see Engine Oil on page 337 for
information on the kind of oil to use and the proper
oil level.”

I’m not recommending waiting to get a warning to check under hood, but you may want to see if you have this feature. I’ve never seen it actuate.

Link to free download:

CSA