Motor Oil Selection for 97 BMW M3

[batook]

I'm looking into selecting a new motor oil for my 97 M3. The car currently has about 151k miles on it. I've had it since 2003 and 105k miles, and have tried Mobil 1 5w30, 10w30, and 10W-40 in the past. Currently it has Mobil 1 10w30 in it. I never go longer than a 5k/6-mo OCI, but in reality, I only put about 3-4k miles on the car per year.

My driving style is much more relaxed now in the M3 than when I first bought it. I wouldn't call it "granny", but certainly a lot less spirited than I was when I was younger; I would say I have a "medium-to-fast" driving style whereas before it was more like "maniacal/a$$hole". No racing whatsoever; this is a daily driver to/from work and 90%+ highway driving. I typically drive 30 miles to/from work (60 miles round-trip) on the freeway doing 70-80mph for a 2-3 day/week work commute with occasional bursts of 90-95mph maybe. Never really let the engine rev over 5k rpms (redline=6500), and I'm installing a 6-speed getrag from an E46 M3 next spring to further reduce highway rpms by an estimated 500rpm or so by using the 6th speed curising gear.

The S52 engine in my M3 specs 5w30 for temps of 50F down to -20F. In warmer climates (never less than 10F), 15w40 is recommended. Here in Colorado, I've typically used the Mobil 1 10w30 or 10W-40 in the summer and 5w30 in winter (or just drained the oil in November and let it sit empty in my garage until May, when I put in a new filter and 10w30 or 10W-40 for the summer when I actually drive the car.

I'm looking at either Mobil 1 0W-40 Euro spec or GC 0W-30. I'm pretty new here, but from what I've read on this site so far, either of these oils would be a good choice for my car. Just wondering if any other BITOG E-36 M3 owners have any advice or opinions in selecting between the two. Another oil that interests me is Pennzoil Ultra, but the winters here get pretty cold, and although I don't drive this car when there's snow on the ground, I'd still feel better using a 0W oil rather than 5W, which is all that PU is presently offered in. Also, since this is a German car, it seems like either the Mobil 1 0W-40 or GC 0w30 Euro-spec oils would be the best choice for this engine.

The engine does sputter and run kind of rough on its current Mobil 1 10w30 oil until it gets warmed up. Sometimes it even throws a CEL code while idilng, which will go away after 50-100 miles of highway driving. I hoping that switching to the Mobil 1 0W-40 or GC 0w30 will help alleviate this problem somewhat, especially on colder mornings.

If I do a used oil analysis, it sounds like I should run the new oil choice for at least 2 OCIs before sending in a sample to ensure its running on purely the new oil vis and not residual 10w30. Speaking of which, are there any deals offered by Blackstone for BITOG users, something like $20 test kits or 5 kits for $100, instead of the $25/kit price listed on their website? That would be nice...

Thanks for any advice on this one. I may end up trying both, but I'm thinking I'll try the Mobil 1 0W-40 first unless the GC 0w30 has shown better used oil analysis in this engine and/or other M3 owners report better results with the GC.

 

[JC1]

Either 0w30 or 0W-40 would be excellent choices.

 

[OVERKILL]

Mobil 1 0w40 has the BMW LL-01 approval, so it should be an excellent choice for this application.

 

[CATERHAM]

Originally Posted By: OVERK1LL
Mobil 1 0w40 has the BMW LL-01 approval, so it should be an excellent choice for this application.

+1
Additionally, it's a better choice to GC due to it's much higher 185 VI vs only 167 for GC. As a result of this, Mobil 1 0W-40 is actually lighter at all start-up temp's as high as 25C.

 

[JHZR2]

+2. But Id also consider running Rotella T Synthetic 5w40.

 

[fdcg27]

Either Syntec 0w30 or Mobil 1 0W-40 would be good choices for this engine, and would be fine all season oils.
Both meet BMW LL-01 specs, which apply to most earlier cars.
Most BMW owners would turn pale at the thought of using Mobil 1 5W- or 10w30 in their cars.
It isn't the oil causing the sputtering or the CEL, either.
How good are your plugs, and have you replaced the ignition wires?
You most likely have some ignition misses going on, and replacing the plugs, if you haven't done so recently, as well as the wires would likely solve this problem.

 

[CATERHAM]

I would add, for winter use, considering the conservative way in which you drive, Mobil 1 0w30 would be a good choice; much lighter than anything else on start-up at temp's below freezing.

Since you're investing in this car I'd suggest installing an oil pressure guage. It's a very useful device and will enable you to optimize your oil viscosity choice to your own application.

 

[fdcg27]

Caterham, Mobil 1 0w30 is a little shy on HTHSv for this engine, at least according to its maker.
Mobil 1 High Mileage 0w30 has an HTHSv of ~3.0, while oils complying with BMW's spec have a minimum HTHSv of 3.5.
You don't think this matters?
Maybe it doesn't, but I'm thinking that BMW had a reason for specifying fairly thick oils, as did Mercedes.
I'm not sure that a mechanical oil pressure gauge tapped into the same spot as the stock sender would tell the whole story, either.

 

[Flying_A]

Mobil 1 0W-40... Can't go wrong.

 

[bodeh6]

German Castrol FTW.

 

[batook]

Thanks for all the replies guys. Seems like a majority of you are recommending the Mobil 1 over GC, so I'll give the Mobil 1 0W-40 a try and see how it goes. They have it at a local Super Wal-mart for $6.36/qt, so that beats the 8.79 price for GC at Autozone (even with the $20 gift card deal for every 5x$20 purchases).

Originally Posted By: fdcg27
It isn't the oil causing the sputtering or the CEL, either.
How good are your plugs, and have you replaced the ignition wires?
You most likely have some ignition misses going on, and replacing the plugs, if you haven't done so recently, as well as the wires would likely solve this problem.


Well it doesn't misbehave like this in the summer, only when the temps drop below 40F or so. The codes it throws never relate to a misfire or anything like that. Plugs might be *just* hitting 30k miles, but they are the OEM Bosch Platinums that were like $8/plug or so, and I thought they were supposed to be good for 60k, but I have to double check that. IAC, I'll change them out next spring.
The S52 has ignition coils, not wires, and I havn't really heard of anyone replacing all the coils as a maintenance item. Usually the codes it throws are related to o2 sensors or MAF stuff. I do probably need to at least clean the MAF, and the o2 sensors are admittedly due. They will get replaced when I drop the exhaust next spring to install the 6-speed getrag. Hopefully everything will get sorted out when I finish all this work.

Since I usually store this car over the winter, is it advisable to drain the oil *before* I store it, or should I run the engine every few weeks during the winter, and then drain the oil in the spring and put in some fresh Mobil 1 0W-40 and OEM Mahle filter?

Oh yeah, one other thing, I do have pretty bad oil consumption in this car, but it's been that way since I bought it 9 years ago. It burns about a quart every 1k or so. I asked an independent BMW mechanic about it when I was living in San Diego and he said that's normal, the car even has a sticker on the cluster that says "check engine oil regularly" to address this problem. No big deal, I just dump in another quart or so every 1k miles, but just wondering if anyone else with this car has this sam consumption issue?

 

[HTSS_TR]

If you don't drive this BMW in winter months, then M1 High Mileage 10W40 may be a better choice in combating oil consumption of 1 quart per 1k miles.

 

[fdcg27]

Gotcha.
I didn't know that the engine had coilover ignition.
Still, the running problems you're experiencing have nothing to do with the oil.
If you're using a quart every 1K, what do your plugs look like?
Any fouling?
Anyway, I would have oil in the engine over the winter.
There is no point in storing the engine without oil in it.
I'd talk about corrosion, but all of the oil lives in the sump anyway, so that wouldn't really be a factor.
I would not start the engine while the car is stored unless you intend to actually drive the car.
You won't get all of that oil up to operating temperature unless the car is driven some distance.
You'll only create additional moisture in the oil, as well as more fuel.

 

[batook]

Originally Posted By: fdcg27
Gotcha.
I didn't know that the engine had coilover ignition.
Still, the running problems you're experiencing have nothing to do with the oil.
If you're using a quart every 1K, what do your plugs look like?
Any fouling?
Anyway, I would have oil in the engine over the winter.
There is no point in storing the engine without oil in it.
I'd talk about corrosion, but all of the oil lives in the sump anyway, so that wouldn't really be a factor.
I would not start the engine while the car is stored unless you intend to actually drive the car.
You won't get all of that oil up to operating temperature unless the car is driven some distance.
You'll only create additional moisture in the oil, as well as more fuel.

All good points and all that makes sense to me. It's really dry here in CO, so moisture condensation in the oil isn't as much of a concern as in more humid areas, but still a valid point. I'll try to take 30-mi+ highway drives at least once a month while it's "stored" if the weather permits.

So my take-away from this thread is to try the Mobil 1 0W-40 over GC 0w30 since it might be *slightly* thicker at op temp (although Dr. Haas states the GC 0w30 is closer to an 0W-40 in reality, so they are roughly equivalent viscosities it would seem), and becaue of its higher VI of 185 over GC's 167. I'm actually a little surprised by this, because from what I've been reading here, people treat the GC like it's made of gold...

 

[antonmnster]

I doubt that the sputtering and CEL has anything to do with the oil.

I'd look into that. Probably a lazy o2 sensor or a vacuum leak. Those are issues that need to be addressed, if anything, from a MPG standpoint.

 

[CATERHAM]

Originally Posted By: fdcg27
Caterham, Mobil 1 0w30 is a little shy on HTHSv for this engine, at least according to its maker.
Mobil 1 High Mileage 0w30 has an HTHSv of ~3.0, while oils complying with BMW's spec have a minimum HTHSv of 3.5.
You don't think this matters?
Maybe it doesn't, but I'm thinking that BMW had a reason for specifying fairly thick oils, as did Mercedes.
I'm not sure that a mechanical oil pressure gauge tapped into the same spot as the stock sender would tell the whole story, either.

The spec' oil of the day was an energy conserving API 5w30 conventional for winter use with ambient temp's up to 10F. Many used a conventional 10w30 in the summer or a 5w30 synthetic for year round use.
A mechanical oil pressure gauge will tell you what your oil pressure and therefore how thick or thin your oil is every for second the engine is running. Does it "tell the whole story"? Yes in terms of the oils operational viscosity but no interms of oil consumption or TBN level.
Running a 0w30 or 5w30 synthetic oil with a HTHSV in the 3.0cP-3.2cP range with not test the minimum viscosity requirements of an M52 engine driven on the street.

I don't know why the OP's oil consumption is so high. I get about 5,000 miles/L in my bimmer on lighter oil. My neighbour who had an E36 M3 got similar oil consumption and he used Mobil 1 5w30 year round.

Anyway, dispite the high oil consumption I wouldn't recommend anything heavier than Mobil 1 0W-40, especially for short trip winter use.

 

[fdcg27]

Caterham, I understand your point.
The lubrication system is a closed loop, so pressure must be constant throughout, right?
Also, if oil were being squeezed out of the main bearings more quickly than it could be replenished, then we would see a drop in oil pressure, right?
Now, do we really know that an oil with the HTHSv of Mobil 1 0w30 can provide an adequate hydrodynamic wedge at the main bearings of this engine under all conditions?
If it can, why did BMW recommend such thick oils when this e36 was new, and why do they now require oils with HTHSv of 3.5 minimum?
Not questioning your rationale, just wondering why BMW isn't on the same page, particularly for US market street driven cars.

 

[batook]

Originally Posted By: antonmnster
I doubt that the sputtering and CEL has anything to do with the oil.

I'd look into that. Probably a lazy o2 sensor or a vacuum leak. Those are issues that need to be addressed, if anything, from a MPG standpoint.


Could be, just always seems to do it with cold oil once the temps drop below 40, and never otherwise. MPG is always 25-26, unless I was driving a little faster since the last fill-up, might drop to 24. Anyway, I'll get the issue sorted during the winter down-time over the next few months.

 

[batook]

Originally Posted By: CATERHAM
The spec' oil of the day was an energy conserving API 5w30 conventional for winter use with ambient temp's up to 10F. Many used a conventional 10w30 in the summer or a 5w30 synthetic for year round use.

Yeah, an independent BMW mechanic I used to take my car to in San Diego only used synthetic 5w30 year-round in that hot climate.

Originally Posted By: CATERHAM
I don't know why the OP's oil consumption is so high. I get about 5,000 miles/L in my bimmer on lighter oil. My neighbour who had an E36 M3 got similar oil consumption and he used Mobil 1 5w30 year round.
Anyway, dispite the high oil consumption I wouldn't recommend anything heavier than Mobil 1 0W-40, especially for short trip winter use.

You mean you burn 1L every 5k miles in your bimmer, and the same story for your neighbor with the M3? That's not bad at all. I have to remember to check the oil at least once a month, and it usually needs a little topping off whenever I check it. If I let it go for 1,000+ miles, it will be over a pint low, but not a full quart. It might lose a full quart if I let it run for 3-4k miles without topping off.

Anyway, sounds like you're recommending 0W-40 or 0w30 Mobil 1. I like both of those oils, so that sounds good to me. Maybe 0w30 in winter and 0W-40 in summer? The 0W-40 is a superior group Iv oil, so maybe I'll just use that year-round, although I would like to see if it likes the lighter 0w30 in the winter.

 

[CATERHAM]

Originally Posted By: fdcg27
Caterham, I understand your point.
The lubrication system is a closed loop, so pressure must be constant throughout, right?
Also, if oil were being squeezed out of the main bearings more quickly than it could be replenished, then we would see a drop in oil pressure, right?
Now, do we really know that an oil with the HTHSv of Mobil 1 0w30 can provide an adequate hydrodynamic wedge at the main bearings of this engine under all conditions?
If it can, why did BMW recommend such thick oils when this e36 was new, and why do they now require oils with HTHSv of 3.5 minimum?
Not questioning your rationale, just wondering why BMW isn't on the same page, particularly for US market street driven cars.

That's right, an oil's viscosity is temperature related so if you keep the oil temperature down you reduce the engines need for a thicker (high HTHSV) oil.
That's way I can run a 0W-20 without issue during the winter months in my Bimmer, the oil temp's rarely gets above 80C.

Why does BMW and most other German manufacturer's now specify a min' HTHSV 3.5cP oil? Because these are sporting cars and the oil temp's can rise quite high when driven hard; i.e., continuous cruising speeds well in excess of 100 mph. But here in NA we can't drive that fast and unless you track your car it's simply not possible to generate high oil temp's. BMW doesn't know if you're going to track your car, hence the min' 3.5cP spec'.
I drive reasonably fast, cruising in the 85-95 mph range, traffic permitting with occational bursts over 100 mph and I've never seen my oil temp's exceed 100C on the street even on the hottest summer days.

Additionally, most manufacturers have gotten away from recommending lighter oils for the winter based on ambient temp's. It still makes sense but with the move to long drain periods that can exceed a year and the advent of synthetic oils it's no longer necessary. For example, Porsche used to recommend 5W-20 for ambient temp's below freezing but with no high speed driving. So what happened if a clueless owner didn't change out the light oil for the summer and took the car for a nice 150 mph run? The engine could be toast and I'm sure it happened often enough for the manufacturers to want to get away from winter use only oils entirely.
The advent of high VI oils like Mobil 1 0W-40 for all ambient temp's and driving conditions made engine oil recommendation very simple. Are there better oils for extreme cold operations; for sure, and for track/racing use, possibly, but for overall street use I don't know of one oil that's better.