[mys_iii]

report that their cars consume oil every few thousand miles? I don't undertand why BMW considers this "within spec". Given the improvements in engine design and manufacturing, shouldn't these engines be consuming no oil at all for the first 100,000 miles? Does anyone know why these engines have such high oil consumption?

[Tom K.]

Most manufacturers still spec consumption of one quart per 1,000 miles (or even 1,000 kms in some cases) as "within the normal range". While most of the complaints of burning a quart per 3~4,000 miles come from turbo owners, my last 5 (non-turbo) Bimmers averaged 1/2 quart every 8,000.

And if your vehicle has gone 100,000 miles without having the oil changed, oil consumption will be the least of your worries.

Tom

[mys_iii]

What I meant by 100,000 miles is that the car should not consume any oil between oil changes. I'm trying to understand exactly "why" these engines consume oil within what I consider so few miles. I've had cars that were 7 years old that didn't consume any oil between oil changes even when driven hard so I don't understand how these newer engines consume so much oil.

[F32Fleet]

Large.number of.BMW's are automatics and urban commuters . Both bode ill for a I6 when break in is considered.

[bmodzelewski]

what is happening to the oil? where is it going? mine burns oil like crazy and the dealership can not find any leaks and i do not see any smoke from the exhaust which would suggest oil burning...

[Brian_TII]

All engines burn oil. No matter how great the rings there will always be some on the cylinder walls that remain to lubricate them. This cannot be changed and is normal. Some cars that "don't burn oil" are actually just diluting oil with fuel in the blow by gases past the rings. Oil is still burned but the burned oilis replaced with fuel and other combustion byproducts. As long as your not consuming a large amount I wouldn't worry about it. 1 qt in 4000 - 5000 miles is more than acceptable in my book. My 330 usually doesn't need any addional oil to meet my 10k mile oil change interval.

[bmodzelewski]

Originally Posted by Brian_TII

All engines burn oil. No matter how great the rings there will always be some on the cylinder walls that remain to lubricate them. This cannot be changed and is normal. Some cars that "don't burn oil" are actually just diluting oil with fuel in the blow by gases past the rings. Oil is still burned but the burned oilis replaced with fuel and other combustion byproducts. As long as your not consuming a large amount I wouldn't worry about it. 1 qt in 4000 - 5000 miles is more than acceptable in my book. My 330 usually doesn't need any addional oil to meet my 10k mile oil change interval.

im at a qt about every 750 - 800 miles... dealer found no leaks and i dont have any smoke coming out of the tailpipes

[Brian_TII]

Ouch... I'd call that too much. Have you replaced or looked at the oil separator? I know that's common esp on the older e46s and the e90s have one too.

[bmodzelewski]

i have not... but where is all of the oil going? wouldnt there be some kind of over abundance of oil somewhere eventually?

[F32Fleet]

Originally Posted by bmodzelewski

what is happening to the oil? where is it going? mine burns oil like crazy and the dealership can not find any leaks and i do not see any smoke from the exhaust which would suggest oil burning...

Some of fuel dilution with the N54 powerplant alone. If previous owner had a tune then it's no surprise

[John 070]

I think the mfg. says there's consumption, to cover the motors that consume oil. Mine doesn't, not a drop (well put it this way the electronic dipstick is always at max).

[mys_iii]

Originally Posted by John 070

I think the mfg. says there's consumption, to cover the motors that consume oil. Mine doesn't, not a drop (well put it this way the electronic dipstick is always at max).

It seems that they claim it's normal when it's just an indication that something with the overall design is not quite right. Perhaps gaskets that wear out sooner than expected or other parts that degrade over time and cause oil consumption? I would not call a quart every 1 - 2K miles normal. My understanding is that modern engines are much more precise than those from 10 years ago so I would expect them to not burn any oil within 8 - 10k miles.

[F32Fleet]

Originally Posted by mys_iii

It seems that they claim it's normal when it's just an indication that something with the overall design is not quite right. Perhaps gaskets that wear out sooner than expected or other parts that degrade over time and cause oil consumption? I would not call a quart every 1 - 2K miles normal. My understanding is that modern engines are much more precise than those from 10 years ago so I would expect them to not burn any oil within 8 - 10k miles.

Some prius engines burn a quart every 1k miles. It's improper break-in. I bet the I4's will not be big consumers because the engine will be working harder. I also bet the SAV don't have same consumption.