BMW and the 10W60 thing???!!!

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There's more to it than just engine speed or temperature. Consider, for example, piston side-thrust forces. A high torque motor will put more side-thrust on the piston than a fast but low torque one. This will also translate into more thrust on the conrod bearings and crank journals.
 
At least with the S54, typical operating temperature tends to be around 85ºC; it might go a bit above 100ºC if you're driving particularly hard. Those temperatures seem pretty low to really require a 10w-60
 
Originally Posted By: terraphantm
At least with the S54, typical operating temperature tends to be around 85ºC; it might go a bit above 100ºC if you're driving particularly hard. Those temperatures seem pretty low to really require a 10w-60

You're absolutely right, which is why most owners that don't take their car to the track use a 0W-40. Remember this, the FF on these cars is just as 5W-30.
And for winter use, if you're not seeing oil temp's much above 85C I'd suggest an A5/B5 0W-30.
 
The factory fill is only kept in for running in and 1000 miles.

A 2.9HTHS oil in a S54 is a bad idea. That's almost half the HTHS of the 10W-60. Give it a bit of fuel and water dilution and it's going to be too thin for the S54 bearings.

Amazes me people can just guess a A5/B5 will 'be ok' as its cold, I guess these are the same guys who think mixing two oils is done how a good idea.

The bearing local temps are still high once warmed up. The bulk sump temperatures might be lower but that's only going to make the fuel and water dilution worse as it won't evaporate as easily.

BMW spec 10W-60 for a reason...
 
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What amazes me are those that think they have an understand of engine lubrication but have no idea of the concept of operational viscosity.
Sump oil temps and bearing oil temp's are linked; the higher the former, the higher the latter. And if you want to know specifically what the operational viscosity is in the bearings at any given moment just install an oil pressure gauge. There is a reason why HTHSV is often called "bearing viscosity".

Yes BMW spec's TWS 10W-60 (not any 10W-60) for a reason, and the possibility of high oil temp's when driven continuously at high rpms and under WOT conditions is the main reason.
And for those that don't know, a typical 3.0-3.1cP HTHSV 0W/5W-30 grade oil is more than 50% heavier at 100C than a nonsheared virgin TWS 10W-60 is at 150C. So running it in an M3/M5 that's not seeing oil temp's much above 85C is a very conservative approach to take. If it were me I'd run a 0W-20 which I've done during the winter in my own Bimmer.
 
Your oil pressure viscometer is measuring the viscosity of the oil as it enters the right angle turn into the bearing.

As I've done and reported the calculations a number of times before, at any reasonable RPM above a couple thousand and with regular bearing clearances the oil passing from the main bearing gallery into the UNLOADED side of the bearing is operating in the high shear range...

Therefore you are measuring viscosity...of the bulk oil, as it enters the unloaded portion of the bearing.

As I've repeatedly demonstrated, the oil temperatures in the LOADED part of the bearing can be 20+ degrees C hotter than the bulk (unloaded feed area). It often doesn't "feel" right to someone with no training, or experience in all facets of bearing lubrication, but the temperature rise IS there, whether posited against or not.

And oil pressure has no relationship to MOFT on the loaded side of the bearing, other than the viscosity of the oil as it enters the unloaded side.

Further, in addition to the oil pressure gauge not seeing what's happening on the loaded side of the bearing, it further, cannot "see" what's going on in the big end bearing. As you would understand the big end is (intermittently) fed already heated oil, suffers the greatest peak load (mains are an average load) and in addition the load is highly cyclic, which tends to pump oil out of the bearing.

Big ends are operating in a whole different world to what can be "seen" with bulk oil temperature and oil pressure.
 
Originally Posted By: CATERHAM
What amazes me are those that think they have an understand of engine lubrication but have no idea of the concept of operational viscosity.
Sump oil temps and bearing oil temp's are linked; the higher the former, the higher the latter. And if you want to know specifically what the operational viscosity is in the bearings at any given moment just install an oil pressure gauge. There is a reason why HTHSV is often called "bearing viscosity".

Yes BMW spec's TWS 10W-60 (not any 10W-60) for a reason, and the possibility of high oil temp's when driven continuously at high rpms and under WOT conditions is the main reason.
And for those that don't know, a typical 3.0-3.1cP HTHSV 0W/5W-30 grade oil is more than 50% heavier at 100C than a nonsheared virgin TWS 10W-60 is at 150C. So running it in an M3/M5 that's not seeing oil temp's much above 85C is a very conservative approach to take. If it were me I'd run a 0W-20 which I've done during the winter in my own Bimmer.



The engine design dictates the viscosity. Not the ambient conditions. Your 328 engine is completely different. How on earth will a oil pressure gauge tell you anything about viscosity??

KV100 is irrelevant as its under almost no shear. HTHS is measured at 150C and 10^7 shear rate, it is supposed to replicate a typical bearing. However the S54 isn't a typical bearing, so you can use a USV rig to look a higher shear rates which many VMs will simple shear out, leaving you with the Newtonian viscosity of the oil to keep bearings apart

S54s have pretty narrow bearings with a high specific torque so you can't run a 0W-20 and expect no issues.

Why do you think BMW refused warranty claims on cars that didn't have the 1000mile oil service ?
 
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Hi,
Shannow - Yes, your comments are relevant IMO. OP and Temp. gauges cannot measure the component/lubricant "stress" at various areas around the engine

As you know I know a little about Castrol/BMW and the 10W-60 lubricant - that said, if an Owner wishes to deviate from the Castrol/BMW recommendations for any reason then a lubricant meeting ACEA A3/B3 would be the minimum for me!
 
BMW still insist on 10W-60s only, but if your happy to go for lower visc I would agree on not going below 3.5cP HTHS. The Castrol TWS formulation was updated about 4yrs ago. It seems many bitog people have noticed this too.
 
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Originally Posted By: Doug Hillary
Hi,
Shannow - Yes, your comments are relevant IMO. OP and Temp. gauges cannot measure the component/lubricant "stress" at various areas around the engine

As you know I know a little about Castrol/BMW and the 10W-60 lubricant - that said, if an Owner wishes to deviate from the Castrol/BMW recommendations for any reason then a lubricant meeting ACEA A3/B3 would be the minimum for me!


Hi Doug

For an engine like the S65, do you think an oil such as M1 0w40 would suffice for a daily driven car seeing no track time?
 
Hi,
gatofast - This from BMW USA;

"*The following is the only recommended and approved synthetic oil for BMW M (Motorsport)
vehicles in the US market with gasoline engines, at the present time.

BMW Long-life rating LL-01 Synthetic Oils for BMW M vehicles
equipped with S54, S62, S65 or S85 engines

Castrol EDGE Professional TWS Motorsport SAE 10W-60 Synthetic Engine Oil,
BMW part number 07 51 0 009 420

or

Castrol Edge Professional OE 5W30 Synthetic Engine Oil
BMW part number 07 51 0 037 195"

Noting the above and the specifications LL01 of M1 0W-40 I would not hesitate to use it in a S65 engine for "everyday" use. Of course everyday use does NOT include track time or "hoon" type driving.
 
Curiously, the Castrol EDGE Professional OE 5w30 data sheets that I can find say LL-04 not LL-01.

And this one says not to use in BMW Gasoline engines outside of the EU:

http://msdspds.castrol.com/bpglis/FusionPDS.nsf/Files/327FECC588E3ADE480257AD3003FBDCB/$File/PDS%20CCSA%20Castrol%20EDGE%20Professional%20OE%205W-30%20English.pdf
 
Originally Posted By: Doug Hillary
Hi,
Shannow - Yes, your comments are relevant IMO. OP and Temp. gauges cannot measure the component/lubricant "stress" at various areas around the engine


I agree with you but that is not the function of OP and OT gauges, they are macro tools not micro. Or to put another way they are reference points from which a safe minimum OP or maximum OT (for a given known lubricant) for an engine as a whole has been already been predetermined.
In the case of OP, since an OP gauge reading is a proxy for operational viscosity it is much more accurate for an engineer or engine tuner to provide the known safe minimum OP value than to recommend a single oil or oil grade if the operating conditions in terms of maximum oil temp's are known to very widely.
 
Hi,
CATERRHAM - Thanks for your little "lesson" in the relevance of OP and Temp gauges - you probably know however that I am already skilled in this area!

My point is that the HTHS viscosity is the critical measurement in various areas within an operating engine - under load/stress or not. Temporary shearing of the lubricant is a critical factor in engine durability!

This is why the Euro Manufacturers sought to have HTHS within their Certification regime via ACEA - at a time when API and even SAE were coming to grips with rapidly changing engine technologies in the hands of Mr & Mrs Average!

It is only a decade or so ago that even the mention of ACEA was derided here on BITOG - most contributors didn't know about it an it's Manufacturer generated & endorsed Certification processes

IMO it is unwise to suggest to Mr & Mrs Average that a reduction in viscosity based on OP and Temp gauges alone is unwise!

IME using the lowest viscosity recommended for a particular application by the Manufacturer is wise!
 
Hi,

error;
This;

IMO it is unwise to suggest to Mr & Mrs Average that a reduction in viscosity based on OP and Temp gauges alone is unwise!

should have read;

IMO to suggest to Mr & Mrs Average that a reduction in viscosity based on OP and Temp gauges alone is unwise!


Sorry, it's the Tropical heat getting to me......or age............or both!!
 
I
Originally Posted By: Shannow
Your oil pressure viscometer is measuring the viscosity of the oil as it enters the right angle turn into the bearing.

As I've done and reported the calculations a number of times before, at any reasonable RPM above a couple thousand and with regular bearing clearances the oil passing from the main bearing gallery into the UNLOADED side of the bearing is operating in the high shear range...

Therefore you are measuring viscosity...of the bulk oil, as it enters the unloaded portion of the bearing.

As I've repeatedly demonstrated, the oil temperatures in the LOADED part of the bearing can be 20+ degrees C hotter than the bulk (unloaded feed area). It often doesn't "feel" right to someone with no training, or experience in all facets of bearing lubrication, but the temperature rise IS there, whether posited against or not.

And oil pressure has no relationship to MOFT on the loaded side of the bearing, other than the viscosity of the oil as it enters the unloaded side.

Further, in addition to the oil pressure gauge not seeing what's happening on the loaded side of the bearing, it further, cannot "see" what's going on in the big end bearing. As you would understand the big end is (intermittently) fed already heated oil, suffers the greatest peak load (mains are an average load) and in addition the load is highly cyclic, which tends to pump oil out of the bearing.

Big ends are operating in a whole different world to what can be "seen" with bulk oil temperature and oil pressure.





Interesting.
Very interesting.

So bulk oil temps don't reflect actual oil temps in the bearing under load and can be much hotter at those spots,thinning the oil at the most critical area.
Very interesting indeed. Thanks Shannow.
 
Originally Posted By: bobbydavro
The factory fill is only kept in for running in and 1000 miles.

A 2.9HTHS oil in a S54 is a bad idea. That's almost half the HTHS of the 10W-60. Give it a bit of fuel and water dilution and it's going to be too thin for the S54 bearings.

Amazes me people can just guess a A5/B5 will 'be ok' as its cold, I guess these are the same guys who think mixing two oils is done how a good idea.

The bearing local temps are still high once warmed up. The bulk sump temperatures might be lower but that's only going to make the fuel and water dilution worse as it won't evaporate as easily.

BMW spec 10W-60 for a reason...




Alright there bud.
You've toucjed on a few points there so time to back up your yip.
Exactly what data have you got that says mixing oils are bad,considering redline encourages doing so to fine tune the viscosity.
And don't even try to bring up that "additive clash" nonsense.
Every used oil analysis I've seen posted here using a frankenbrew of different brands and grades show no issues whatsoever with the oil nor were there any anomalies in the wear metal trended data,so please enlighten us with evidence to the contrary. And not some opinion,data from a lab please.
And BMW specifies a 10w-60 to cover their rears,period. It's a bandaid fix.
For a new guy you've got some pretty firm beliefs. I wonder what previously banned member you are.
Don't tell me. Me and my friends enjoy the chase.
 
Originally Posted By: Clevy
Originally Posted By: bobbydavro
The factory fill is only kept in for running in and 1000 miles.
..........

BMW spec 10W-60 for a reason...



For a new guy you've got some pretty firm beliefs. I wonder what previously banned member you are.
Don't tell me. Me and my friends enjoy the chase.



Wow! Sherlock Holmes strikes again.

bobbydavro Registered: 02/01/09

Clevy Registered: 11/11/10
 
Originally Posted By: Clevy

And BMW specifies a 10w-60 to cover their rears,period. It's a bandaid fix.


No, as has already been mentioned, BMW specs/spec'd the TWS 10w-60 because it is a known quantity to them and is necessary in some engines for proper protection at Autobahn speeds and the oil temps that go along with them.

That said, there were two cars/engines that BMW "band-aided" with the TWS product, the first was the E46 M3 and the S54 engine, which was having rod bearing failure issues. The TWS was then spec'd for it as apparently it was thought it would reduce the failures. There was eventually a recall for this problem. The second was the E39 M5 prior to 03/00 to deal with the ultra low tension rings and excessive oil consumption. Post 03/00 cars spec'd LL-01 as they received revised rings that fixed the issue.
 
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