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My 535 has 37500 miles on it. What is the normal oil consumption after driving 6000 miles (easy driving). My measurements show a loss of approx. 4%. is this normal?
 

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My 535 has 37500 miles on it. What is the normal oil consumption after driving 6000 miles (easy driving). My measurements show a loss of approx. 4%. is this normal?
Neither of our 535i's (2012 & 2014) consume any oil between the factory recommended interval.
 

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535i: I measure the volume of the oil I drain out. I change my oil about every 8k miles. My last oil change was at 54.5k miles, and I consumed about 850ml in 8300 miles. At 16.5k miles, I'd only consumed about 400ml in 6.8k miles. At 38.2k miles, I'd consumed about 700ml in 7.7k miles.

The service manager at the dealership I use says that's typical for an N55, and that a lot of their customers get a low-oil warning light right before the scheduled 10k or 11k mile oil changes.
 

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535i: I measure the volume of the oil I drain out. I change my oil about every 8k miles. My last oil change was at 54.5k miles, and I consumed about 850ml in 8300 miles. At 16.5k miles, I'd only consumed about 400ml in 6.8k miles. At 38.2k miles, I'd consumed about 700ml in 7.7k miles.

The service manager at the dealership I use says that's typical for an N55, and that a lot of their customers get a low-oil warning light right before the scheduled 10k or 11k mile oil changes.


It’s pretty sad that a $70,000 car is expected to consume oil due to poor engine design.


Sent from my iPad using Bimmerfest mobile app
 

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It***8217;s pretty sad that a $70,000 car is expected to consume oil due to poor engine design.


Sent from my iPad using Bimmerfest mobile app
The BMW V8's are usually the ones with the oil consumption problems. Most, if not all of those problems are caused by the intense heat in those engines baking and drying out the valve stem seals, and by varnish (deteriorated oil) causing the piston rings to stick in the closed position (against the piston, instead of against the cylinder wall).

The BMW in-line six's are generally happy motors. Although, some of the S54 engines (E46 M3) had oil consumption problems. But, some didn't, including mine.

High performance engines get hot. The two hottest parts of the engine are the piston and the exhaust valves.

On trick engines, the exhaust valves have liquid sodium inside the valve stems to effectively transfer heat up the stem and then into the cylinder head. Pistons are kept from melting by spraying the bottom of them with oil. Because pistons get so hot and they're typically made of aluminum, the clearance between the piston and the cylinder wall must be large enough to account for thermal expansion. But, that can cause some oil consumption when they're not near their maximum operating temperature.

Turbocharges will also consume some oil. They also make the engine's performance higher, causing the pistons to get hotter, requiring greater clearances. High performance also means the engine is working harder for it's size, and will incur more wear. My oil consumption is steadily going up, now twice what it was when the engine was new but broken in. That means there's wear taking place.

Things are still better today than they were back in the old days. I worked in the courier office of a bank when I was back in college in the 1980's. They had about 15 Fords, about a dozen station wagons with V6's, and three vans with V8's. They all burned about a quart every 2000 miles using conventional oil. (My synthetic oil speech fell of deaf ears, as did my speech about tires lasting longer if you keep sufficient air pressure in them.) My parent's 1985 Mercury with a 5.0 liter V8 burned a quart of synthetic oil about every 2300 miles during break-in and about every 2800 miles after break-in. (Synthetic oil evaporates less, and protects against wear better.)

I had a 1976 VW Rabbit that burned a quart of oil every 300 miles before I got rid of it at 155k miles. At some point, I stopped changing the oil and just fed the engine the used synthetic oil out of my parent's Mercury.

Every time I buy a BMW, I ask myself "Is this one going to be an oil burner?" I'm zero for tree. (One of my four BMW's was in an unfortunate mishap, and not around long enough to get an oil change.)

The all-time Putzer fleet champion of oil economy (the inverse of oil consumption) is my lowly Chevy Cobalt with a 2.4 liter engine. It burned almost nothing up until about 100k miles, and now at 120k miles is only burning about 750ml of synthetic oil in 8000 miles. Those engines supposedly have a reputation for burning oil. But, GM didn't require synthetic oil for them, because Bill Bob says "I ain't gunna buy no car that needs $7 (per quart) oil."
 

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It’s pretty sad that a $70,000 car is expected to consume oil due to poor engine design.


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It's not poor engine design. It's virtually impossible to keep oil from getting past the rings. The oil is needed to lubricate the rings against the cylinder walls. The trick is to lubricate without letting oil past the rings.
 

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My 535 has 37500 miles on it. What is the normal oil consumption after driving 6000 miles (easy driving). My measurements show a loss of approx. 4%. is this normal?
Id say its better than normal. My 535i also consumes a tiny amount between changes. Id only worry if I had to top up between changes.
 
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