M3 V8 Oil level gauge

[Ratslaaf]

I have a question around the oil consumption, or at least the oil level gauge.

The oil level on the car has been slowly dropping till it got to a point that it stated I had to add 1l of oil. I've done this now but the car still states that I need to add oil? I'd guess that the min to max levels are around 1l or so, so surely the level should've changed?

Something doesn't add up, as I can't see any oil leaks under the car or belly plate, nor do I see any smoke whatsoever coming out of the pipes. Clean as a whistle. Car sounds good as well with no hesitation or any other symptoms. Also, when the car is cold I don't see a puff of smoke when it starts.

This is really weird and I've picked up many forums that people don't trust the oil level gauge at all. Thing is, I don't want to overfill it either.

What's the experience from others here?

 

[Ratslaaf]

Just went now an added yet ANOTHER 1l of oil and now it's at MAX oil. Grrrrrrr

I'm really distrusting the oil level sensor now. But this does tell me the car is using oil. I'm just not sure what's acceptable use of oil on the car though and I have a suspicion that the type of oil being used will have a pretty big effect on oil consumption of this type of car, bearing in mind it doesn't appear that the car is leaking anywhere.

 

[KPM3_30]

I hate the method of checking oil on the e90. The onboard computer takes forever to calculate the oil level and I'm not sure I trust it. Hopefully someone with one can shed some light..

 

[akash]

Maybe just do the engine oil change that you were planning to do.

You will then know how much oil is actually in the car and you can monitor the oil consumption.

 

[Fordkoppie]

After adding the first 1L of oil, you should have driven the car until it was hot, and while the measuring display was showing, hold the stalk to take instantanious reading.

It was still showing the "average" reading.

By adding 2L, you have now overfilled it.

Those level sensors are the most retarded thing I have ever seen on a motorcar.

What was wrong with having a dipstick?

 

[Spiro]

hi guys


i do know that you can get a retrofit dip stick kit for the car, i think either ECS Tuning or VAC Motorsports sells this...

 

[Ratslaaf]

^^^ Thanks man - I didn't know that it was possible to get an instantaneous reading? I've never bothered reading the manual - cause real men never do. I guess I'll have to put my big girl panties on now and brush up on these things.

I am doing the oil change this weekend so hopefully I can have a known point of reference from here on out.

Interestingly it usually takes around a minute to measure the oil once warmed up. After adding oil just now, it took almost 3 minutes to read the oil level. That should've been a hint that it averages the readings as I'm thinking there's waaay too much hysteresis between measurement extremes.

Next time, I'll wait for oil to warm up, stop the car and then take an instant reading rather.

 

[S65B44]

^^^ Thanks man - I didn't know that it was possible to get an instantaneous reading? I've never bothered reading the manual - cause real men never do. I guess I'll have to put my big girl panties on now and brush up on these things.

I am doing the oil change this weekend so hopefully I can have a known point of reference from here on out.

Interestingly it usually takes around a minute to measure the oil once warmed up. After adding oil just now, it took almost 3 minutes to read the oil level. That should've been a hint that it averages the readings as I'm thinking there's waaay too much hysteresis between measurement extremes.

Next time, I'll wait for oil to warm up, stop the car and then take an instant reading rather.

In the 5 months I have my M3, I have had to add oil once, and till today (3 months later) the oil level is the same. Take your reading as mentioned above, when engine is hot, and take it on a level surface.

Something else to consider...
http://store.bimmerworld.com/e9x-m3-s65-oil-dipstick-retrofit-kit-p2042.aspx

 

[OppositeLockMT]

Really missed the dipstick with our E60/E70, readings always seemed to be a bit off. Can't fully trust a computer as it's prone to malfuctioning.

 

[Speed Freak]

Hi Ratslaaf, I bought my first ever BMW last year and learning about these cars myself now. I know in some cases you have to anitialise some faults or warnings to clear it,maybe that's the case with the oil level as well after filling it up. I don't know which model you've got,but I've got an e90 330d and mine got a dipstick which the salesman pointed out as the gearbox's and I reasently learn't that it is the engine's. Second I want to point out that BMW uses Castrol oil . In my experience many cars running on Castrol uses oil until yuo change to another brand, then the oil usage is gone.
I recently changed my oil as well and ofcause I'm a believer of Shell. Maybe you should try another brand as long as you go for a fully synthetic oil I believe it's worth a try ...
Greetings
Enjoy that V8 power.

 

[Ratslaaf]

Thanks bud,

Yeah my car has no dipstick so I'm buggered there. Based on info Fordknoppie gave, I've figured out that if you hold the BC button for long, it'll do a proper new reading on the oil level, as opposed to an average reading it normally does. I'll be draining some oil the weekend anyway as I need to send the oil for analysis in order to set a benchmark for the car.

I'm a big believer in Liqui Moly and that's what I'm going to be using on the car going forward. Just need to go through a flush process for the next 500km first.

 

[Blue Shirt]

After adding the first 1L of oil, you should have driven the car until it was hot, and while the measuring display was showing, hold the stalk to take instantanious reading.

It was still showing the "average" reading.

By adding 2L, you have now overfilled it.

Those level sensors are the most retarded thing I have ever seen on a motorcar.

What was wrong with having a dipstick?

To be honest, having both a dipstick and oil level sensor is better, such as found on my X5 with N62 engine. The level sensor can warn you about a low oil level while you are driving and therefore unable to pull the dipstick.

The dipstick is the true measure of oil level which I use to compare the level sensor reading with. In my case, if the dipstick shows minimum level, the level sensor still shows 2 out of 5 bars remaining.

 

[Fordkoppie]

Thanks bud,

Yeah my car has no dipstick so I'm buggered there. Based on info Fordknoppie gave, I've figured out that if you hold the BC button for long, it'll do a proper new reading on the oil level, as opposed to an average reading it normally does. I'll be draining some oil the weekend anyway as I need to send the oil for analysis in order to set a benchmark for the car.

I'm a big believer in Liqui Moly and that's what I'm going to be using on the car going forward. Just need to go through a flush process for the next 500km first.

My e90 was accidentally filled with 5W30 by the dealers in Nelspruit.

This is how I bought the car and completely oblivious of this matter.

Because I am pedantic, I changed the oil 1 week after I got the car to Liqui Moly 10W60 GT1 as recommended by their site.

The car was extremely sluggish afterwards and took forever to warm up compared to the 5W30.

That is when I started reading up on the matter (From the link I posted in your other thread), and I would never again use LM, Castrol or whatever in a 60 weight in the s65.

The thick oil combined with owners who revs it too hard when not warm enough I believe to be the singular cause of the much reported bearing failure.

I will say it again...

If I ever have another s65, it will run on Mobil 1 0W40, which BTW is the OEM recommended oil for the GT3 porches which are also +8k rpm engines.

I believe the only place where the thick 10W60 will offer superior lubrication, is if you track the car constantly where oil temperatures are almost never below 100deg C. In any other environment where it will see frequent cold starts, go thin

 

[moranor@axis]

If warmed up properly would the 10w 60 not be better?

surely a thicker oil would prevent narrow bearings making contact better than a thinner oil under compression from the piston? GT3 was build for thinner oil and the bearing would have been sized correctly for it

 

[Ratslaaf]

Thanks gents,

Yes, there's a little debate going on in the background regarding the oil at this very moment. I'll keep you guys updated of the result.

 

[Fordkoppie]

If warmed up properly would the 10w 60 not be better?

surely a thicker oil would prevent narrow bearings making contact better than a thinner oil under compression from the piston? GT3 was build for thinner oil and the bearing would have been sized correctly for it

I believe it does more damage when cold than we can possibly imagine.

The thing is that the S65 has similar tight bearing clearances to the GT3/2 engines

---

To be honest, having both a dipstick and oil level sensor is better

I agree having both is the ultimate solution.

But if I can only have 1, it would most definitely not be the sensor

---

GT3 was build for thinner oil

Elaborating on this matter, the GT3's rings and bore honing patterns were also developed from the start to cope with the thin oil, whereas the s65 was not.

Therefore, oil consumption will increase with thin oil in the S65.

But with regular checks/topups, this is not an issue

 

[moranor@axis]

If warmed up properly would the 10w 60 not be better?

surely a thicker oil would prevent narrow bearings making contact better than a thinner oil under compression from the piston? GT3 was build for thinner oil and the bearing would have been sized correctly for it

I believe it does more damage when cold than we can possibly imagine.

The thing is that the S65 has similar tight bearing clearances to the GT3/2 engines

Im more worried about bearing width than clearances a lighter oil with a wide bearing will be able to take the same force as a narrower bearing with thicker oil Im just not sure how the s65 will handle the lighter oil when designed for thicker... need to do more reading on the s65 with lighter oil and try find some oil analisis

 

[Fordkoppie]

http://www.m3post.com/forums/showthread.php?t=892838

A thread with clearances. The rest of the tread also contains very informative links

You will note that the 2011 onwards rod bearing normal clearances have been increased

 

[moranor@axis]

had a read to summarize it seems the issue stems from very tight clearance between the bearing crank and conrods... in this case a thinner oil will help

also BMW NA have approved 5w30 5w40 and 0w40 oils for this engine

unless there there is bottom bearing shell wear on an S65 with thinner oil I see no reason not to run it on a street car and it will be better for the engine

 

[Fordkoppie]

had a read to summarize it seems the issue stems from very tight clearance between the bearing crank and conrods... in this case a thinner oil will help

also BMW NA have approved 5w30 5w40 and 0w40 oils for this engine

unless there there is bottom bearing shell wear on an S65 with thinner oil I see no reason not to run it on a street car and it will be better for the engine

Exactly.

All these tight clearances are brilliant, if only there was a way to keep the oil at 100deg always and forever