excessive oil consumption

[FC in TO]

The car is a 98 M3 and has roughly over 100,000km. i was under a assumption that a small amount of oil burning/consumption is acceptable for the M3 (also depends on the driving and grade of the oil used).

But early this yr (spring) i did an oil change and decided to measure just how much oil it consumes with no-track driving. and then i got...

>> 1L for every 1500km (about 1000miles) << normal street driving.

I do not think this is 'normal' although the car does not experience any external leak or visible signs of oil burning smokes. BMW calls this 'acceptable' (they didn't say 'normal') which i find a little off.

can someone suggest to me some of the areas that might be causing the problem?

Will a compression test tell me anything? Oil seperator? etc..

[Mazrx7tt]

Are you running normal oil or synthetic?
I was running standard oil and I had oil consumption.
As soon as I changed to synthetic I have 0 oil consumption and its been 4k miles since I changed oil in the motor.

[FC in TO]

I drive pretty slow and soft on the road with a good mix of hwy and street conditions. I did quite a bit of tracks last year so I thought it has something to do with my track driving.

So, in order to make this measurement somewhat meaningful, I managed to monitor the oil usage this spring with normal daily driving and fresh new oil (Mobil1 10w-30, but I have tried several others in the past such as AMSoil, Castrol, etc... with somewhat the same result).

As for the car itself, it runs fine with no smoke whatsoever, not during start up and not during full throttle hard acceleration. nothing.

[GQ_Style]

I heard that up to 1qt/1000miles is considered "normal". Some people have better luck trying different weights of oil. If your car is running fine, I wouldn't worry about it too much.

[hal9000]

Yep, BMW considers that acceptable. Are you sure you're not leaking oil? Check valve covers, pan gasket, rear main seal, etc....

[M3Jokster]

do u think u have any oil leaks...before your next oil change, lift up your car, clean up as my much oil stains if neccessary, then add some oil dye into the motor crank.

drop the car and drive for couple of miles. then lift the car up, w/ an aide of a black light, u can see the flourescent dye if there's any oil leaks.

i had the same problem..turned out it was the Dipstick O-Ring. it was on the side of the powersterring pump hoses, and i thought it was leaking form there.

from then on....zero oil consumption. my car is a daily driver no tracking.

[paul e]

>>I heard that up to 1qt/1000miles is considered "normal"<<

It is....I have a white paper from them, and they consider virtually any useage not exceeding 1 qt per 400 miles to be 'normal'!!

[Ken ///M3]

I've had my 98 M3/2 since it was new and I use the standard BMW synthetic oil for all my changes. Driving style varies from slow city trips to very aggressive on the back roads and freeways.

I've never had to add even a quart between changes. I think it has much to do with how you break the car in and not exceeding 3K rpm until the temp is up + 15 minutes.

Ken

[LuxoM3]

I drive the HELL out of my 1996 M3 and it DRINKS 1 QT. every 1000 miles.



You are not alone. Do a search on oil consumption and you'll find A LOT of M3 (and M5 owners) with the same issue.

Trying different brands and weights of oil helps. My car used to drink about 1 qt. of Mobil 5w-30 every 400 miles!
I used Castrol 5w-50 Synthetic and it has slowed oil use to around 1k-1.2k miles.

No biggie.

Oil use varies from M3 to M3.

Hope this helps as misery loves company.


-LuxoM3

[FC in TO]

thanks for the reply guys,

so i guess it is 'acceptable' even tho i still don't buy the fact that it is.

dealers basically shut me out by saying it's acceptable by BMW and they would just leave it like that.

independent shops have also suggested running different grades and weight. one shop sugguested that a normal engine should not consume any, but he still checked my vaccum in the system to see if it were pumping too much oil somewhere.. the reading was normal.

i am in the process of doing another oil monitoring with a different brand and weight to see if it helps or not.