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Xc70 vanishing oil

Last August, with about 76,000 miles on it, the oil light on my xc70 came on when I was making a U-turn. I took the car into the dealer and was told it was down almost 4 quarts. The “cause” was the breather box which was replaced for a substantial amount of money. About 5k miles later the same thing happened. Again I was down over 3 quarts but the breather box was fine. There is no leak and absolutely no indication that oil is burning (no smoke, smell, residue in the tailpipe). The speculation was that that the oil was somehow vaporizing in a line between the pan and the block. I didn’t buy that.
Now after three more visits; I have been bringing the car in every 1k for an oil change and consumption check (the dealer has absorbed this cost) they have determined it is losing about ½ quart every 1k miles. They have not identified why. All they say is that I can rebuild the engine (new rings and pistons). This is ridiculous! 85k on the car and it needs a new engine. This was a certified pre-owned Volvo with 11k when I bought it and all service has been done by the dealer.
Does anyone have any insight into this?

If you’re looking for support on that problem you might not like this forum. Anyone who drives 5,000 miles without checking and adding oil as necessary deserves the catastrophic failure that their negligence causes. The dealer doesn’t owe you anything.

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Many manufacturers use a rule that up to one quart per thousand miles is considered to be acceptable, for what that’s worth, and your usage is only half of that.

I don’t understand how you let the oil get down four quarts the first time and especially how you let the oil get down three quarts over 5,000 miles the second time, after you knew you had an issue. Do you not check your oil regularly? I’m afraid that the engine damage is your fault here. By the way, if you didn’t shut off your engine the moment that you saw the oil pressure light, then you made things even worse.

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The first time you let the oil run 4 quarts low probably did enough damage to the engine. The second time you let it run down to 3 quarts low after 5,000 miles certainly didn’t help. The rings get starved for oil, and create gouges in the cylinder walls and ring surfaces. These gouges allow for more oil to slip past the rings and get burned in the cylinder, just burning out of the tailpipe. There is no cure for bad rings and gouged cylinder walls but a bottom-end overhaul or rebuild.

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The problem is definitely due to not checking the oil level on a regular basis and reading between the lines a bit, not changing the oil often enough as you refer to 5k miles with apparently no change or check being done over that mileage span.

This is not a factory defect or dealer problem and 4 quarts down means the engine was being damaged for no telling how long before that 4 quarts low was discovered.
The oil light came on and this was entirely preventable.

I’m wondering if we are jumping to conclusions about the OP’s engine.

While I do not endorse the behavior of never checking the oil between oil changes, we only know that the oil light came on while the OP was making a U-turn. We do not know if it was on as he drove to the dealer or how far the dealer was. (Still a risky situation - I agree).

The oil light comes on when the pump begins sucking air. If the oil light is off, it means the pump pickup is getting oil, which means adequate oil pressure.

So if the only info we have from the OP is the oil light came on briefly, how does that translate into concluding the OP has an engine with destroyed bearings, rings, and cylinder walls? And how can we conclude the brief oil light is responsible?

We’ve all changed oil + filter on many engines where the oil light comes on for 3-5 seconds upon restart. It’s not comforting, but it doesn’t lead to trashed engines.

While the oil light coming on is really bad news, if it truly only came on during a U-turn, isn’t there a chance something else is occurring here? I’m not looking for flames - only for shared critical thinking.


When an engine with a capacity of 5 or 6 quarts is driven 5,000 miles while losing 4 quarts the oil quality of the oil remaining when the light flashed would be seriously deteriorated and the temperature of the oil when there is a bare minimum can rise significantly in a short amount of time even at moderate speeds. I wouldn’t want to get too far from home in that car.

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Maybe the oil light came on just briefly, but instead of pulling over and checking the oil right there the OP went to the dealer, and we don’t know how soon.
Just another person who is helpless and clueless about the most basic care of what’s likely their second most valuable possession.
Reminds me of my SIL who thought there was no need to be concerned about going on a road trip in her car with a leaking, half-flat tire.

…but back to the cause of the original problem. I presume that the breather box to which he refers is in the PCV system. Does anyone here know, Is the breather box the only place where there is an oil mist eliminator in this engine? Sudden excessive oil consumption on a relatively low mileage car is usually traced to either a leak or the PCV system. My niece’s Pathfinder has a chronic problem with the oil drain holes in the oil mist separator inside her valve cover getting plugged with sludge (they are tiny). When that happens, the separator gets full of oil and the PCV starts sucking the oil over to the intake manifold.

I had two V70XC’s one a '98 and the other a 2000. Both burned oil at a rate of 1/2 qt per 1000 miles for the '98 which had about 150K miles on it, and about one quart every 1000 miles for the 2000 which had only 40K miles on it.

These are turbo charged motors that tend to run a bit “hot” in general and are tough on the oil as the turbocharger uses the oil to help cool the turbo. There are lots of oil lines on the car many with “0” ring seals which can seep or leak a tad.

I didn’t consider the oil use as a problem I just topped off the oil every 1000 miles and checked the oil level every few weeks. I found some brands of oil burned off faster than others. I also changed the oil every 3K with regular oil. I’d recommend full synthetic if you want to extend the oil change interval up to 5K miles or more.

Therefore, if the OP is using regular oil and going to 5K between changes and not checking the oil level every couple of weeks (or every 1K miles) then I’d expect a Volvo turbo to be out of oil. Hopefully the motor wasn’t damaged in a major way by running so low on oil. While there was oil pressure except brief episodes where the “oil light” came on; the oil remaining in the crankcase was very hot, and some coking and varnish deposits could result. If there are no oil passages blocked by coked oil and sludge then the motor should do OK without a rebuild as long as the oil is kept between the marks on the dipstick. If there are loud knocks, pings, or rattles that didn’t exist before that could be a sign of bearings worn, or rod ends getting loose from lack of lubrication.

“The “cause” was the breather box which was replaced for a substantial amount of money. About 5k miles later the same thing happened.”

Find a decent independent mechanic…Have him clean, service, replace the entire PCV system from end to end, not just the valve itself…That may help.

Otherwise, consign yourself to adding a quart of oil every now and then, like millions of other drivers…

I would guess that the “breather box” is the anti-backfire valve/PCV valve. When they fail pressure will build in the crankcase and oil will be lost in all the usual places.

Now let’s examine “vanishing oil” what might have happened in this case. Let’s start at an oil change with 5 qts of fresh oil. At 1000 miles you are down 1/2 quart as per the oil use info given in the post. At 2000 miles you are down 1 qt leaving 4 in the crankcase.

At 3000 you are down another 1/2 quart with 3 and 1/2 left in the crankcase. But, that oil has been working harder the last 1000 miles because there is less oil in the motor so it is recirculating faster. So, maybe you are now down more than 1/2 qt because there is less oil and it is less fresh. Lets say then from 2K mile to 3K miles you actually go down 1 qt instead of 1/2. So at 3K miles you are down 2 qts with 3 remaining.

Now, these 3 qts are not fresh and are working even harder so from 3K to 4K you lose 1 and 1/2 quarts.

Now at 4K miles you are at 1 and 1/2 qts left in the motor. That is enough for oil pressure, but that little bit of oil is working super hard and getting very hot and it is vaporizing and burning off even faster.

Before you get to 5K miles your oil light is going on. The oil did vanish, it was burned off by overuse and overheating. If you keep the oil level between the marks on the dipstick between oil changes you will be adding 2 qts of oil to the motor to maintain the oil level and this is perfectly normal.

I respectfully disagree that the oil light staying off means that adequate oil pressure exists. Most oil lights are turned off at very low oil pressures around the 3 or 4 PSI range.
Three or four PSI may kill the light but it doesn’t provide much protection to the crank bearings which face pressures of 1500-2000 PSI on a running engine.
That’s like a shoving match between a Yugo and a Kenworth.

At some point (and apparently it may never happen, car owners are going to have to take a little responsibility for automotive basics such as checking the oil level.

When someone drops in for moral support and gets a dope slap it is unlikely that they will come back. Mr tillman is hoping that the dealership has more sympathy for him than the heartless cretins here. Someone needs to start a brotherly love thread.

Tillman KNOWS he is screwed, he was just hoping for a little sympathy here…This is not the place to find sympathy…

What length oil change interval are you using? 1/2 quart every 1K miles and the oil level being down 4 quarts indicates at least 8K miles since your last oil change or checking the dipstick. There are many people out there that are running long oil change intervals, but I suspect in most cases it’s causing more $'s worth of damage to their engine than they are saving on oil changes and this may be the case with your engine. Motor oil is designed to keep impurities and combustion by products in suspension in the oil, but the longer it goes without changing the more contaminants there are in the oil which leads to sludge and reduces it’s ability to fight heat and friction causing faster wear and/or significant engine damage. You also need to get in the habit of pulling the dipstick out and checking the level on a weekly basis. Your Volvo with well under 100K miles is using about half as much oil as my '88 Ford Escort which has 518,700 miles. It has averaged an oil change at less than 4K mile intervals over the life of the engine and I watch the oil level, adding oil when it gets 1/2 quart low.

There are many drivers out there that don’t know how to do anything to their car other than put gas in it, start it and drive it. If every driver would spend 10 minutes walking around their car and under the hood once a week checking tire tread depth/inflation pressure, checking the condition of belts and hoses, checking/topping off the oil, transmission fluid, coolant, power steering fluid, brake fluid and battery water they would find that their cars would be safer, more dependable and last much longer. I think minor maintenance such as checking the inflation pressure/condition of tires, and fluid levels should be a part of the driver’s test in all states.

I’ll skip the lecture. You’ve been beaten enough. But I agree with the others that you’ve neglected your engine and need to learn to maintain your vehicle properly.

One of the problems I’m having is interpreting the descriptions in your post. There is no “line between the pan and the block”, or a “breather box” that would suck up oil. Oil is pumped up from the pan by the pump and pushed through all the appropriate passages to lubricate the parts.

Is it possible that He told you the Positive Crankcase Ventilation system was plugged and that was causing excess oil usage? Can you write to us exactly what the shoporder says?

Having said that, you should know that 1/2 qt every 1,000 miles is considered acceptable oil usage. If that’s correct, than…fortunately… the only problem you have is that you don;t check your oil. I’d suggest that rather than have them change the oil every 1000 miles you learn how to monitor the oil level yurself. By regularly pulling the dipstick and looking at the “fill” and “full” lines you yourself can determine how much oil your car is using. Simply write down the mileage each time it needs a quart and divide. If you know how to use your trip odometer, you can use that to monitor miles driven between quarts.

If it turns out that you’re really using only 1/2 quart every 1000 miles (1 qt every 2000 miles) than you are one very lucky fella. Running an engine on low oil levels can be deadly. Think of it this way, if there’s 8oz of gump and dilutants in your crankcase, your engine will be far better lubricated if that 8oz of gump is diluted in 5 quarts of oil than in 1 quart of oil.

My father has the same issue happening with his xc60. The dealer said he has had to fix 20 of the same issues recently. I’m thinking these people on here beating you up work for Volvo and know they’ve got a problem they don’t want anyone to figure out. People need to speak up…this is clearly a recall waiting to happen.

The conspiracy theory is a bit much…