5w50 in place of 10w60 for BMW M3

ROFL... which part? We do know that these engines are based off the P84, and how many races did F1 require that an engine last prior to being rebuilt? 2 races or the season? Obviously I'm being a little tongue-n-cheek but a tiny part of me thinks the bearing issues are related to the design carryover from the P84.
Could very well be.
 
ROFL... which part? We do know that these engines are based off the P84, and how many races did F1 require that an engine last prior to being rebuilt? 2 races or the season? Obviously I'm being a little tongue-n-cheek but a tiny part of me thinks the bearing issues are related to the design carryover from the P84.
The part where you suggested that BMW knowingly sold engines with F1-type rebuild intervals for sedans with full factory warranties, and that you heard about this from an authoritative source.

If all you wanted to say is that there might be some subtle design characteristic due to attempted tech transfer that contributes to the problem, then sure. As long as we're clear that that's just speculation.

The S85 and S65 may have some high-level similarities with the P84, and the blocks were all made in the same place. That doesn't imply that the design criteria, individual parts, or end products are more than vaguely comparable (they aren't). Nor does it contradict the reality that the S65 and S85 are many, many times longer-lived than race engines.

The rod bearing issue is most likely a matter of error or misjudgment by BMW, exaggeration by the community, or some combination thereof. The idea that BMW was like "no one will care if they have to swap these rod bearings every 2 years lol" is... not plausible.
 
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The part where you suggested that BMW knowingly sold engines with F1-type rebuild intervals for sedans with full factory warranties, and that you heard about this from an authoritative source.

If all you wanted to say is that there might be some subtle design characteristic due to attempted tech transfer that contributes to the problem, then sure. As long as we're clear that that's just speculation.

The S85 and S65 may have some high-level similarities with the P84, and the blocks were all made in the same place. That doesn't imply that the design criteria, individual parts, or end products are more than vaguely comparable (they aren't). Nor does it contradict the reality that the S65 and S85 are many, many times longer-lived than race engines.

The rod bearing issue is most likely a matter of error or misjudgment by BMW, exaggeration by the community, or some combination thereof. The idea that BMW was like "no one will care if they have to swap these rod bearings every 2 years lol" is... not plausible.
True. People literally go around and compare rod bearings just bcs.
On another note, while both engines are derived from P84, P84 was spinning almost 21,000rpm's. There are a lot of things that needed to be changed for street use.
 
The part where you suggested that BMW knowingly sold engines with F1-type rebuild intervals for sedans with full factory warranties, and that you heard about this from an authoritative source.

If all you wanted to say is that there might be some subtle design characteristic due to attempted tech transfer that contributes to the problem, then sure. As long as we're clear that that's just speculation.

The S85 and S65 may have some high-level similarities with the P84, and the blocks were all made in the same place. That doesn't imply that the design criteria, individual parts, or end products are more than vaguely comparable (they aren't). Nor does it contradict the reality that the S65 and S85 are many, many times longer-lived than race engines.

The rod bearing issue is most likely a matter of error or misjudgment by BMW, exaggeration by the community, or some combination thereof. The idea that BMW was like "no one will care if they have to swap these rod bearings every 2 years lol" is... not plausible.
Oh of course but wouldn't it be interesting to know what the physical differences are between the P84 and the S8/65 with regards to the crank and bearing width? All engines have over-square bores but the S8/65 are less so with a slightly longer stroke (eg, street use, reduced redline) yet the cylinder spacing is greater on the P84 (103.5mm - 102mm) vs S8/65 (98mm).
 
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My S85 powered M6 W/6 speed manual, still runs great 11 years later. I mostly have used Redline 10w60. I always get the engine up to operating temperature, before taking the engine to the rev-limiter. It sees the rev-limiter every time it's driven, just to enjoy the sound of a high-rpm V-10.

Despite the internet telling me for as long as I've owned it, that it's a ticking time-bomb, it's been fine...
 
My S85 powered M6 W/6 speed manual, still runs great 11 years later. I mostly have used Redline 10w60. I always get the engine up to operating temperature, before taking the engine to the rev-limiter. It sees the rev-limiter every time it's driven, just to enjoy the sound of a high-rpm V-10.

Despite the internet telling me for as long as I've owned it, that it's a ticking time-bomb, it's been fine...
You should take out rod bearings and compare them :ROFLMAO:
 
Oh of course but wouldn't it be interesting to know what the physical differences are between the P84 and the S8/65 with regards to the crank and bearing width? All engines have over-square bores but the S8/65 are less so with a slightly longer stroke (eg, street use, reduced redline) yet the cylinder spacing is greater on the P84 (103.5mm - 102mm) vs S8/65 (98mm).
Oh, heck yes.

One curiously underappreciated trait of the S85/S65 (IMO) is low-ish rod bearing surface area vs. many engines with similar specific output and redlines. AFAICT this is mainly because the rods themselves, and thus the rod bearings and crank journals, are relatively narrow. I wonder if they were trying to push limits on how closely they could pack rods on the crank and cylinders in the block, and maybe one reason for the tight rod bearing clearances was to ensure adequate load capacity with moderate bearing surface area.
 
my 2000 m5 called for the 10w60 for some reason. that V8 wasn’t a screamer at all, all out of steam by the time it hit the 7k redline

after dumping in almost $200 of TWS i found out it could use LL01 without issue......
 
my 2000 m5 called for the 10w60 for some reason. that V8 wasn’t a screamer at all, all out of steam by the time it hit the 7k redline

after dumping in almost $200 of TWS i found out it could use LL01 without issue......

I had an '01, LOL, called for LL-01. The pre 03/00 cars called for TWS not because the engine needed it, but because the low tension rings meant oil consumption and the heavier oil was used to mask it.

IIRC, peak power was ~6,600RPM for the S62, but it didn't fall off sharply after that, it tapered down gently until the 7K limit.
 
IF the OEM bearings have durability issues, is there an aftermarket brand/bearing material that holds up better?
IIRC it's more of an issue with how the engine was designed, rather than the bearings being the weak point.
 
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IF the OEM bearings have durability issues, is there an aftermarket brand/bearing material that holds up better?
As I understand it the rod bearing journals are too narrow (i.e. diameter) which reduces the physical surface area of the bearing combined with extremely tight clearances. I don't know but as d00df00d alluded to about the con-rods perhaps the rods themselves were from the BMW parts bin rather than using custom rods which would complement larger bearing journals. In any case the BMW fix was to revise the bearings with ones which have a larger clearance and a material change (tin from copper). I think the revised bearings are working fine but I stopped following when I realized that it was going to be exceedingly difficult to locate and maintain a lightly used example.

Because these engines a naturally aspirated with oversquare bores their low rpm torque is around 300 ft/lbs at almost 4,000 rpms. They really were race engines adapted for street use and I think that's what hurt them. People buy horsepower but drive torque. Almost all initial buyers were leases who used the vehicle to commute with occasional stints at the track.

I still think the E90/92 M4 is one of the best looking examples today.
 
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As I understand it the rod bearing journals are too narrow (i.e. diameter) which reduces the physical surface area of the bearing combined with extremely tight clearances. I don't know but as d00df00d alluded to about the con-rods perhaps the rods themselves were from the BMW parts bin rather than using custom rods which would complement larger bearing journals. In any case the BMW fix was to revise the bearings with ones which have a larger clearance and a material change (tin from copper). I think the revised bearings are working fine but I stopped following when I realized that it was going to be exceedingly difficult to locate and maintain a lightly used example.

Because these engines a naturally aspirated with oversquare bores their low rpm torque is around 300 ft/lbs at almost 4,000 rpms. They really were race engines adapted for street use and I think that's what hurt them. People buy horsepower but drive torque. Almost all initial buyers were leases who used the vehicle to commute with occasional stints at the track.

I still think the E90/92 M4 is one of the best looking examples today.
That is where the problem is with the majority BMW's, not only M models.
 
I just don't understand how they have made this mistake like with five engines now.

I mean, they certainly test the engines at severe duty and knew this was happening. So they either don't care enough to redesign it or it's one of those cases where they felt it will last long enough as is.

I agree that the bearings being too small is the likely culprit, and that is certainly not easy to change. You can make the large end of the rod bigger but then you also have to make the crank journal bigger, which adds weight, which might not let you meet your 8400 RPM goal, or necessitates much more expensive, lighter rods, etc etc.

So they probably gave it the old "good enough" and let it go. But then you would think they would fix it the next time... Or the next...

Mind you, the newer stuff seems to be ok, so maybe they figured it out.
 
As I understand it the rod bearing journals are too narrow (i.e. diameter) which reduces the physical surface area of the bearing combined with extremely tight clearances. I don't know but as d00df00d alluded to about the con-rods perhaps the rods themselves were from the BMW parts bin rather than using custom rods which would complement larger bearing journals. In any case the BMW fix was to revise the bearings with ones which have a larger clearance and a material change (tin from copper). I think the revised bearings are working fine but I stopped following when I realized that it was going to be exceedingly difficult to locate and maintain a lightly used example.

Because these engines a naturally aspirated with oversquare bores their low rpm torque is around 300 ft/lbs at almost 4,000 rpms. They really were race engines adapted for street use and I think that's what hurt them. People buy horsepower but drive torque. Almost all initial buyers were leases who used the vehicle to commute with occasional stints at the track.

I still think the E90/92 M4 is one of the best looking examples today.
Rods and pistons are shared with the S85.

It was indeed thought that the updated BMW bearings had no copper. This was later proved false, and the initial source of that info was quietly updated, though few people seem to know that. The new bearings do in fact have a trimetal construction including copper; composition is unknown, though they most likely are lead-free with an aluminum alloy top layer. It's unclear whether clearances changed; if they did, the difference is minimal. Eccentricity seems to have increased and tolerances seem to have improved significantly.

Engines with the updated BMW bearings have occasionally suffered bearing failures, though it's not clear how many, nor is it always clear why. Updated BMW bearings that are pulled from service look discolored and worn, even after only a few thousand miles. However, it was recently demonstrated that the discoloration most commonly seen is superficial and does not represent wear through the top layer. There are multiple possible reasons for the discoloration other than wear, but no one has done the legwork to rule any of them in or out. No one's measuring these bearings, either. So, really, we have no idea how they're wearing. Better info will likely be slow to come, largely because so many people are already satisfied with the current theory about what the problem is and how to fix it.

Aftermarket bearings with increased clearance are showing considerable promise. However:

1. There haven't been enough examples pulled after significant mileage to compare to the massive number of examples of OE bearings; and

2. Although there have been engine failures with them, those failures have all been chalked up to something else (install error, other things failing first, etc.) and many are thus dismissed before they can be scrutinized or counted.
 
I just don't understand how they have made this mistake like with five engines now.

I mean, they certainly test the engines at severe duty and knew this was happening. So they either don't care enough to redesign it or it's one of those cases where they felt it will last long enough as is.

I agree that the bearings being too small is the likely culprit, and that is certainly not easy to change. You can make the large end of the rod bigger but then you also have to make the crank journal bigger, which adds weight, which might not let you meet your 8400 RPM goal, or necessitates much more expensive, lighter rods, etc etc.

So they probably gave it the old "good enough" and let it go. But then you would think they would fix it the next time... Or the next...

Mind you, the newer stuff seems to be ok, so maybe they figured it out.
The problem was for some S54 engines and S65 and S85 But generally, BMW's suffer from the type of buyers and the fact that inline 6 engines (though we are talking here V10 and V8, but very specific engines) suffer more from lubrication issues due to the nature of inline 6 engines. They are difficult to cool off, oil is more important when it comes to cooling than in an average V6 engine etc.
The reason why newer engines are more stout is that turbos allow extremely high performance throughout rev. bend. BMW still makes engines that differ by being inline and still having high rev. considering they are turbos. The current issue on S55 engines, a crank hub (very rare) is the direct consequence of pursuing very high rpms for forced induction engine.
But it is the price to pay for play. BMW never slapped turbos on and called it a day, or shoveled just huge engine in. There is always something special about those engines that separate from MB or Audi, regardless that maybe they do not on paper perform any better. However, if you take S54, S65, 85 into consideration and competition, those engines and cars were bounds and leap ahead of the competition and much more thrilling to drive.
 
The problem was for some S54 engines and S65 and S85 But generally, BMW's suffer from the type of buyers and the fact that inline 6 engines (though we are talking here V10 and V8, but very specific engines) suffer more from lubrication issues due to the nature of inline 6 engines. They are difficult to cool off, oil is more important when it comes to cooling than in an average V6 engine etc.
The reason why newer engines are more stout is that turbos allow extremely high performance throughout rev. bend. BMW still makes engines that differ by being inline and still having high rev. considering they are turbos. The current issue on S55 engines, a crank hub (very rare) is the direct consequence of pursuing very high rpms for forced induction engine.
But it is the price to pay for play. BMW never slapped turbos on and called it a day, or shoveled just huge engine in. There is always something special about those engines that separate from MB or Audi, regardless that maybe they do not on paper perform any better. However, if you take S54, S65, 85 into consideration and competition, those engines and cars were bounds and leap ahead of the competition and much more thrilling to drive.

The E46 M3 is maybe my favorite car ever, so I am not trying to be biased or anything here, they just made some very weird errors that shouldn't happen.

While I understand the S65 is an awesome engine (barring the bearing thing), the 4.2 in the RS4/R8 is one hell of an engine as well. But it has its own problems with carbon buildup and fifty feet of timing chains :ROFLMAO: . Then the Merc 6.2 is a great engine also but has problems with head bolts stretching. So it is weird why these engines have such basic problems.

By modern standards the engine in my car (2.5T) is one of the best engines in the world. The S55 has been pretty good and the S58 looks great so far.
 
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