Thoughts on the E9x from a BMW Tech

[davesaddiction]

From a post on Jalopnik's Car Buying (my responses in italics):

Your resident BMW wrench says this car isnt actually bad to own. Manual trans is solid, aside from leaks the DCT is solid, the body and suspension is solid. Only real issues on this car are an evaporator thats a seemingly 100% failure rate as they are made of thin aluminum and corrode, the odd broken valve spring in the engine but the most worrisome issue is bottom end problems. They have been known to chuck rods rather dramatically or have bearing wear. They actually have very thin and small bearings and seem to be an issue to be aware of. However it should be ok if you keep up on maintenance, don't beat on it or boost it (they dont like that, trust me i have half of a rod for a souvenir)

I really appreciate your input! Mine is still on its original clutch after 70k miles (and I don't baby it) and I did get my evaporator replaced (under original warranty, thankfully). I'll be keeping an eye on the bearings with Blackstone reports. Of the bearing failure(s) you've seen, how many miles were on the engine, or was the failure related to a supercharger, poor warm-up discipline, or something?

Definitely boosted. We've seen a lot of non boosted cars too so i think the thin bearings really can't handle the boost and that just speeds it along. Mileage? It varies, a lot. 30k was the lowest and that car had a blower, we also had a thrust bearing fail super early on a car but that was an anomaly as ive never seen another. I HIGHLY recommend oil analysis on this motor and the S85 V10. I also would do your oil changes 5-7k miles depending on use. It does seem to effect early cars more than late, but when they change bearings or make minor internal changes they never tell us. This wont effect every car but its something thats known to happen and should be taken care of. Its nowhere near as prevalent as say the IMS failure on Porsches, but just as pricey.

Other than the odd motor mount and rotors that warp at the track its really a great car. I honestly think it will be the "E39 M5" of M3s. Last of the greats. Sure the new one is trick, but its the size of an old 6 series, and sounds like shit. Nothing sounds like that E9x's S65.

Thanks for all the good info. I've been changing oil at 10k intervals (15 is insane), but I'll probably switch to half that or 7.5 on your recommendation. Some owners are swapping to Mobil1 0w30 (*edit - I meant 0w40...) - not sure of your thoughts on that. I'll probably also look into a preventative bearing swap at some point in the not-too-distant future.

I love mine, and you're right, that sound...

No need to worry about bearing swaps unless your oil analysis comes back with an issue, and by that time it could have more then just bearings as the material works its way into everything. The S85 was like this and they would show up with VANOS issues due to the bearing material damaging the VANOS pump and units.

0-30 is far too thin. That would do damage for sure. All our other cars run 5w30 so we have it on tap but BMW spec'd 10w60 for a reason. My guess is most owners that are switching would rather pay $8 a quart than $16 for the right oil.

Our new cars for '14 have dropped into the 6-8k range for services. After years of us bitching about it damaging engines long term, eatting up seals, and causing issues with VANOS units and turbos seems like engineering finally beat out the bean counters and BMW figured it out. Thats a big expense if you figure now maintenance will DOUBLE the amount of oil changes for 4/50 but its less of a cost than the warranty claims and pissed off customers when there 7 year old 90k mile 550 needs a $8k reseal and valve guide seals..... or CPO pays for it...

Great advice - thanks again.

[Helmsman]

Nice reading, thanks mate.

[m3ray]

Good info, just as I suspected about supercharging. Keeping it in NA seems to be the way to go if you want to maxmize longevity.

[Kurt_OH]

Originally Posted by m3ray

Good info, just as I suspected about supercharging. Keeping it in NA seems to be the way to go if you want to maxmize longevity.

Is there anyone, anywhere who doesn't realize that adding a supercharger to ANY engine, especially adding 50% HP to an already high specific output engine is going to significantly reduce longevity?

[m3ray]

Originally Posted by Kurt_OH

Is there anyone, anywhere who doesn't realize that adding a supercharger to ANY engine, especially adding 50% HP to an already high specific output engine is going to significantly reduce longevity?

Agreed. But just as we type here, there is a SC thread where people are saying they have had no issue with tens of thousands of miles driven.

http://www.m3post.com/forums/showthread.php?t=1055546

The ancedotal evidence is all over the place. I am choosing to err on the side of caution. The car is plenty fast to me already. The potential for engine damage, the added weight and heat are not appealing to me.

[BrewRifle]

Superchargers are NOT causing bearing failures. Stop spreading misinformation.

[m3ray]

Originally Posted by BrewRifle

Superchargers are NOT causing bearing failures. Stop spreading misinformation.

Well this is coming from a BMW tech who works on these cars for a living. What are your credentials?

He's stating in accelerates wear in an engine that is already at the limits bearing wise. And that makes sense.

[///M Power-Belgium]

10W60 for a reason.... I knew that !
And how can SC causing bearing failure as the most bearing failures had no SC ?
THX for sharing .

[BrewRifle]

As stated already, a supercharger puts extra strain on ANY and ALL engines, but is not specifically wearings bearings out 10x more than NA motors. A SC is not the cause for bearings to fail, we can blame BMW's engineers for their brilliant clearances.

[Kurt_OH]

Originally Posted by ///M Power-Belgium

10W60 for a reason.... I knew that !
And how can SC causing bearing failure as the most bearing failures had no SC ?
THX for sharing .

If there are 2x as many bearing failures in stock engines as SC engines, but 200x as many stock engines as SC engines, then the claimed stat that "most" bearing failures are in stock engines is incredibly misleading, and wholly irrelevant to the discussion.

Why would SC increase failures?

More heat, more force on the bearings which is more load on the bearings and more likely to decrease oil flow, more likely to experience preignition. Also, folks going through that expense and risk are very likely to use more power, more of the time than an "average" M3 owner.

[thekurgan]

Dave,

Thanks for posting, I think I saw this "live" on the site; what he states makes sense.

For all the rest of the bearing discussion(s), these are my thoughts:

[Sinful]

Originally Posted by davesaddiction

0-30 is far too thin. That would do damage for sure. All our other cars run 5w30 so we have it on tap but BMW spec'd 10w60 for a reason. My guess is most owners that are switching would rather pay $8 a quart than $16 for the right oil....[/B]

The engineers may have made a mistake with the bearings, however their oil recommendation was not for the bearings but for the entire engine. Save your bearings with 0-30 maybe, but create a new problem ...maybe. Sounds like the above is confirmation of this.

The problem with all these oil recommendations is that if your engine grenades and you go to BMW and try to get it fixed under warranty they have their ammunition...did you use our oil recommendation? NO, sorry then, you messed up the engine because you didn't follow our recommendations...

[Shredicus]

Just a correction: mobil 1 0w-40 is what we have been dabbling with

[///M Power-Belgium]

Originally Posted by SinfulM3

The engineers may have made a mistake with the bearings, however their oil recommendation was not for the bearings but for the entire engine. Save your bearings with 0-30 maybe, but create a new problem ...maybe. Sounds like the above is confirmation of this.

The problem with all these oil recommendations is that if your engine grenades and you go to BMW and try to get it fixed under warranty they have their ammunition...did you use our oil recommendation? NO, sorry then, you messed up the engine because you didn't follow our recommendations...

Indeed a mistake and that during 10 years no matter what oil is used !
Actualy it became a worldwide mistake....

[Sinful]

Originally Posted by m3ray

Well this is coming from a BMW tech who works on these cars for a living. What are your credentials?

He's stating in accelerates wear in an engine that is already at the limits bearing wise. And that makes sense.

Agreed^
More power = more wear/stress on engine.

[Sinful]

Originally Posted by BrewRifle

As stated already, a supercharger puts extra strain on ANY and ALL engines, but is not specifically wearings bearings out 10x more than NA motors. A SC is not the cause for bearings to fail, we can blame BMW's engineers for their brilliant clearances.

We all know the engine is sensitive to bearing failure. At unfortunately, any given time and essentially for no reason, other than poor engineering. So isn't a supercharger increasing the probability of said bearing failure?

I mean if your doctor says your grandpa has a heart problem you don't recommend he follow you to do wind sprints ...

[davesaddiction]

Originally Posted by Shredicus

Just a correction: mobil 1 0w-40 is what we have been dabbling with

Yeah, sorry about that. I noticed my mistake and made an edit just before your post...

[Z K]

Originally Posted by davesaddiction

Yeah, sorry about that. I noticed my mistake and made an edit just before your post...

He responded about 0w30 when you asked about 0w40? He mentions 5w30 in his response as well which is thinner than 0w40. I would agree with him that 0w30 is too thin.

[Kurt_OH]

Unless you're beating on the engine cold, the "0" low end number is IRRELEVANT to the conversation of bearing failure. In fact, it likely REDUCES the chances, since cold lubrication is superior.

The reason you wouldn't run a 0W-30 is because 30 is not NEARLY enough for the temps an engine with these specs would generate. That 30 is going to be about 3 on track, when you're seeking about 10.

The difference between 0W-30 and 0W-40 at cold start of the engine is the difference between water and H20. The exact same applies to 5W-30 vs. 0W-30 at full operating temp: IDENTICAL.

[gatorfast]

Who is this "car tech" and what is this q&a in reference to? Not sure anything new was really said here. Everyone knows there may be risks with a supercharger and I don't think anyone is using 0w30.

[FogCityM3]

Nice work!

[davesaddiction]

Originally Posted by Z K

He responded about 0w30 when you asked about 0w40? He mentions 5w30 in his response as well which is thinner than 0w40. I would agree with him that 0w30 is too thin.

No, I messed up with my question, so he answered in respect to 0w30...