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      01-14-2014, 12:45 AM   #1915
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This weekend I re-torqued the 702/703 bearings back in place and took the eccentricity measurements at 3/8 inch from the parting line (20 and 160 degrees). This is the location recommended for correct eccentricity measurements. The goal was to see if re-torque would affect these measurements. Simple answer after looking at this graph: no.

It's hard to see, but the new line is in green and overlays exactly on top of the red line. You can see the new sets of green dots on the graph. The green dots represent the new measurements. Measurements were not taken at 5, 45, 90, 135, and 175 degrees as part of this re-do.

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      01-14-2014, 08:56 AM   #1916
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Quote:
Originally Posted by regular guy View Post
Simple answer after looking at this graph: no.


Imagine that.
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      01-16-2014, 12:04 AM   #1917
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Quote:
Originally Posted by regular guy View Post
That's why they are stated as opinions...as no further proof is required.
Well, almost. Your closing narrative in the long post I quoted sounds quite a bit stronger in many places than pure opinion/speculation. Thus I thought I would offer some alternate opining.

Quote:
Originally Posted by regular guy View Post
Today I sent six sets of bearings to Clevite for analysis.
...
Great idea. The group of bearings you sent though are highly biased (2/3rd of the 6 sets of bearings) by being from supercharged engines which obviously have much higher combustion pressures and therefore should have a much high propensity for wear, more rapid wear and more severe wear. It seems pretty obvious from most comments along this whole thread that to really solve this problem and to best understand what BMW may or may not have done with bearings and oil, we should be sticking to the analysis of lightly modified cars and certainly no supercharged cars.

Any particular reason for this strong biasing of the data set?

Quote:
Originally Posted by regular guy View Post
This weekend I re-torqued the 702/703 bearings back in place and took the eccentricity measurements at 3/8 inch from the parting line (20 and 160 degrees). This is the location recommended for correct eccentricity measurements. The goal was to see if re-torque would affect these measurements. Simple answer after looking at this graph: no.
Excellent and conservative work that helps validate the prior 088/089 eccentricity values. Thanks.
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      01-16-2014, 12:19 AM   #1918
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Quote:
Originally Posted by swamp2 View Post
Great idea. The group of bearings you sent though are highly biased (2/3rd of the 6 sets of bearings) by being from supercharged engines which obviously have much higher combustion pressures and therefore should have a much high propensity for wear, more rapid wear and more severe wear. It seems pretty obvious from most comments along this whole thread that to really solve this problem and to best understand what BMW may or may not have done with bearings and oil, we should be sticking to the analysis of lightly modified cars and certainly no supercharged cars.

Any particular reason for this strong biasing of the data set?
Reason: It's all I've got. However if you look at some of the supercharged engines, the number of miles they were supercharged were very low (1800 in one case). But regardless, I sent what I had...and it turns out that's all I had.

Big shout out to EAS for sending me their bearings from the 106000 mile engine and allowing them to be sent to Clevite. They will promptly go back to EAS and back on display in their showroom when Clevite is done.
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      01-16-2014, 04:22 AM   #1919
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Quote:
Originally Posted by catpat8000 View Post
It would be interesting to see sales volume by year. For example, the entire economy melted down in Q4 2008 and car sales in the US, in 2009, fell off a cliff, especially expensive car sales. 2010 was not much better. Maybe in 2009 BMW only sold a fraction of the cars they sold in 2008 and 2011.

Does anyone know if this data is available?

Pat
Good call....tracking down the figures was harder than I thought - in the end I emailed "Sickfinga" the guy who has been collating the production numbers and these are the numbers he kindly sent me. The total numbers are greater than previously noted in the linked PDF (on the previous page) as it contains the final data for LCI E93 to end of production.


2008 9010
2009 4146
2010 2047
2011 8616
2012 2453
2013 3984

For a total production of 30256 M3s for the USA/Canada market.

Below I've added 2008 & 2009 & 2010 together, left 2011 separate (as the date of change from 088/9 to 702/703 bearings is uncertain) and then added 2012 & 2013 together - as this helps to even out the rates due to the low numbers.
I've not included the supercharged engines, oil pump or valve failures.
Dividing the production numbers by fails gives a rate per 1000 cars.

2008/9/10 15203 cars @ 10 fails = 1/1520
2011 8616 cars @ 7 fails = 1/1230
2012/13 6437 cars @ 5 fails = 1/1287

I've started a new thread for this topic to stop this one from getting further cluttered up and because it might get a bit lost in here.
http://www.m3post.com/forums/showthread.php?t=935368
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      01-18-2014, 06:44 PM   #1920
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Loosely relevant - my first oil analysis. My car is a 2008. Everything low/below average or in range except lead just a bit high. No concern though on that according to Blackstone.

Probably a better question for Blackstone but can this type of analysis really provide an advanced warning indication of significant bearing wear or impending failure (due to wear only of course)? Looking at the bearings photos in this thread, the progressive wear down to copper and the most severely damaged bearings with large pieces flaking away, it seems pretty obvious that this truly can be such a great preventative indicator. The metal removed from the bearings has to go somewhere. Who wants to have their engine dropped and bearings inspected when it is a total crap shoot as to whether or not new bearings may be needed.
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      01-18-2014, 06:55 PM   #1921
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I've got full bearing clearance specs for the F10 M5. I will post them after I pull them all together.
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      01-18-2014, 07:15 PM   #1922
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Quote:
Originally Posted by regular guy
I've got full bearing clearance specs for the F10 M5. I will post them after I pull them all together.
How is it the F10 M5 engine specs are available and not for the S65?
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      01-18-2014, 07:30 PM   #1923
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Quote:
Originally Posted by 96LTWM3 View Post
How is it the F10 M5 engine specs are available and not for the S65?
Beats the crap out of me. I kind of backed into finding them for the F10 M5. I tried the same back door method for S65 and it still came up blank.

I hope I didn't speak too soon. I have the full ROD bearing specs for F10 M5...I didn't check for main bearing specs. I'll see if I can get those too.
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      01-18-2014, 08:32 PM   #1924
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Quote:
Originally Posted by regular guy
Quote:
Originally Posted by 96LTWM3 View Post
How is it the F10 M5 engine specs are available and not for the S65?
Beats the crap out of me. I kind of backed into finding them for the F10 M5. I tried the same back door method for S65 and it still came up blank.

I hope I didn't speak too soon. I have the full ROD bearing specs for F10 M5...I didn't check for main bearing specs. I'll see if I can get those too.
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      01-19-2014, 01:43 AM   #1925
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It looks like BMW made quite a few changes to the bearings on the F10-S63 M5 engine. I kind of backed my way into finding it like this.

I had access to the BMW software the dealers used. I started snooping around the S63 engine details. I first looked up rod bearing clearance, and just like the S65, the entry for clearance was blank. So out of curiousity, I decided to look over the S63 rod bearing replacement instructions. BMW instructions the service tech to check the clearance with Plastigage. The software provides a link you can click to check for proper clearance. I clicked the link, and I found the missing S63 bearing clearance specifications. Next of course I tried the same thing on the S65. But there was no luck, clicking the same link for the S65 engine brings up the same blank spec sheet that I've seen many times.

Here's an overview of the F10-S63 M5 bearing changes.
  1. Bearings are thinner.
  2. BMW made it impossible to mix up the blue (upper) and red (lower) rod bearings.
  3. Clearances were increased.
  4. The thick TWS 10W60 oil is gone, and LL01 0W30-5W40 oil is in.

Thinner bearings

The S65 connecting rod bore is 56mm and the rod journal is 52mm. This leaves for a 2mm thick bearing for the upper and lower shells. The S63 connecting rod bore is 57.6mm and the rod journal is 54mm. This leaves the connecting rod bearing 1.8mm thick. That is slightly thinner than the 2mm S65 bearing.

Changes to the upper and lower bearings

If there was ever any doubt BMW wanted BLUE bearing shells on the upper connecting rod, and RED bearing shells on the lower connecting rod, then the S63 engine resolved that ambiguity. On the S65, the blue and red bearing shells are ever so slightly different thickness than each other (with blue/upper being thicker). This caused some to believe BMW did this intentionally to set clearances more accurately. The S63 engine leaves no room to hold on to that belief any longer. The upper blue and lower red bearings are keyed differently and can only fit into their proper position. It's no longer possible to install the red on the upper and blue on the lower as it is on the S65. Here's a photo of what the new bearings look like and it shows how they are keyed differently.



Increased rod clearance

The S65 has rod clearance that ranges from smaller than Clevite recommendations on older 088/089 bearings, to barely within Clevite recommendations on the newer 702/703 bearings. The S63 rod bearing clearance is even larger than the extra clearance on the S65 with the latest 702/703 bearings.

The S65 with 702/703 rod bearings has a nominal 0.00165 inch clearance on a 52mm journal, giving a clearance to journal ratio of 0.00081 inch/inch. The S65 mains have a nominal clearance of 0.00180 inch on a 60mm journal, giving a clearance to journal ratio of 0.00061 inch/inch. The S63 improves this somewhat on the rods, but makes the mains even tighter. The S63 rod clearances are 0.00187 inch on a 54mm journal, giving a clearance to journal ratio of 0.00088 inch/inch. The S63 main clearances are 0.00181 inch on 65mm journal, giving a clearance to journal ratio of 0.00051 inch/inch.

Back to thinner oil

The oil experts in this thread have always said the TWS 10W60 oil is too thick for the tight clearances of the S65. The F10-S63 M5 engine goes away from the thick 10W60 oil by going back to LL01 0W30-5W40 thinner oil. I will try to get a print out of these oil recommendations along with the latest LL01 approved oil list.

By the numbers

Here's how the F10-S63 M5 engine clearances compare to the other engine clearances being tracked by this thread.

BMW ///M Engines (Main Bearings)
Sorted by Model
ModelEngine
Max RPM
Oil
Min(mm)
Avg(mm)
Max(mm)
Min(SAE)
Avg(SAE)
Max(SAE)
Size(mm)
Ratio(mm)
Size(SAE)
Ratio(SAE)
RPM-Clr Ratio
E28 M5S38B35 (Main)
6900
0-30 to 5W40
0.020
0.033
0.046
0.00079
0.00130
0.00181
59.987
0.0006
2.362
0.00055
1254
E30 M3S14 (Main)
6900
0-30 to 5W40
0.020
0.033
0.046
0.00079
0.00130
0.00181
54.987
0.0006
2.165
0.00060
1150
E30 M3S14 (Main)
6900
0-30 to 5W40
0.030
0.050
0.070
0.00118
0.00197
0.00276
55.000
0.0009
2.165
0.00091
759
E34 M5S38B35 (Main)
6900
0-30 to 5W40
0.020
0.033
0.046
0.00079
0.00130
0.00181
59.987
0.0006
2.362
0.00055
1254
E34 M5S38B35 (Main)
6900
0-30 to 5W40
0.030
0.050
0.070
0.00118
0.00197
0.00276
60.000
0.0008
2.362
0.00083
828
E34 M5S38B36 (Main)
7200
0-30 to 5W40
0.020
0.033
0.046
0.00079
0.00130
0.00181
59.987
0.0006
2.362
0.00055
1309
E34 M5S38B36 (Main)
7200
0-30 to 5W40
0.030
0.050
0.070
0.00118
0.00197
0.00276
60.000
0.0008
2.362
0.00083
864
E36 M3S50B30 (Main)
7280
0-30 to 5W40
0.020
0.033
0.046
0.00079
0.00130
0.00181
59.964
0.0006
2.361
0.00055
1323
E36 M3S50B32 (Main)
7600
0-30 to 5W40
0.020
0.033
0.046
0.00079
0.00130
0.00181
59.964
0.0006
2.361
0.00055
1381
E36 M3 VertS52 (Main)
6800
0-30 to 5W40
0.020
0.039
0.058
0.00079
0.00154
0.00228
59.987
0.0007
2.362
0.00065
1046
E39 M5S62 (Main)
7000
10W60 (-02/2000)
0.025
0.038
0.050
0.00098
0.00148
0.00197
69.964
0.0005
2.754
0.00054
1306
E39 M5S62 (Main)
7000
5W30 (+03/2000
0.025
0.038
0.050
0.00098
0.00148
0.00197
69.964
0.0005
2.754
0.00054
1306
E45 M5S38B38 (Main)
7200
0-30 to 5W40
0.030
0.050
0.070
0.00118
0.00197
0.00276
60.000
0.0008
2.362
0.00083
864
E46 M3S54 (Main)
8000
10W60 (-02/2000)
0.019
0.036
0.052
0.00075
0.00140
0.00205
59.964
0.0006
2.361
0.00059
1351
E46 M3S54 (Main)
8000
5W30 (+03/2000
0.019
0.036
0.052
0.00075
0.00140
0.00205
59.964
0.0006
2.361
0.00059
1351
E60 M5S85 (Main)
8250
10W60
0.029
0.037
0.046
0.00115
0.00144
0.00180
59.984
0.0006
2.362
0.00061
1353
E92 335N54 (Main)
7000
0-30 to 5W40
0.020
0.033
0.046
0.00079
0.00130
0.00181
55.996
0.0006
2.205
0.00059
1188
E92 M3S65 (Main)
8400
10W60
0.029
0.037
0.046
0.00115
0.00144
0.00180
59.984
0.0006
2.362
0.00061
1378
F10 M5S63 (Main)
7000
0-30 to 5W40
0.020
0.033
0.046
0.00079
0.00130
0.00181
64.977
0.0005
2.558
0.00051
1378
Ferrari 328 GTS3.2L (Main)
7700
10W40
0.013
0.032
0.051
0.00051
0.00126
0.00201
62.986
0.0005
2.480
0.00051
1516


BMW ///M Engines (Rod Bearings)
Sorted by Model
ModelEngine
Max RPM
Oil
Min(mm)
Avg(mm)
Max(mm)
Min(SAE)
Avg(SAE)
Max(SAE)
Size(mm)
Ratio(mm)
Size(SAE)
Ratio(SAE)
RPM-Clr Ratio
E28 M5S38B35 (Rod)
6900
0-30 to 5W40
0.020
0.038
0.055
0.00079
0.00148
0.00217
47.983
0.0008
1.889
0.00078
883
E30 M3S14 (Rod)
6900
0-30 to 5W40
0.020
0.038
0.055
0.00079
0.00148
0.00217
47.983
0.0008
1.889
0.00078
883
E34 M5S38B35 (Rod)
6900
0-30 to 5W40
0.020
0.038
0.055
0.00079
0.00148
0.00217
47.983
0.0008
1.889
0.00078
883
E34 M5S38B36 (Rod)
7200
0-30 to 5W40
0.020
0.038
0.055
0.00079
0.00148
0.00217
47.983
0.0008
1.889
0.00078
921
E34 M5S38B38 (Rod)
7200
0-30 to 5W40
0.030
0.050
0.070
0.00118
0.00197
0.00276
49.000
0.0010
1.929
0.00102
706
E36 M3S50B30 (Rod)
7280
0-30 to 5W40
0.028
0.049
0.070
0.00110
0.00193
0.00276
50.000
0.0010
1.969
0.00098
743
E36 M3S50B32 (Rod)
7600
0-30 to 5W40
0.026
0.047
0.068
0.00102
0.00185
0.00268
49.000
0.0010
1.929
0.00096
792
E36 M3 VertS52 (Rod)
6800
0-30 to 5W40
0.020
0.038
0.055
0.00079
0.00148
0.00217
45.000
0.0008
1.772
0.00083
816
E39 M5S62 (Rod)
7000
10W60 (-02/2000)
0.029
0.048
0.067
0.00114
0.00189
0.00264
49.000
0.0010
1.929
0.00098
715
E39 M5S62 (Rod)
7000
5W30 (+03/2000
0.029
0.048
0.067
0.00114
0.00189
0.00264
49.000
0.0010
1.929
0.00098
715
E46 M3S54 (Rod)
8000
5W30 (-02/2000)
0.030
0.050
0.070
0.00118
0.00197
0.00276
49.000
0.0010
1.929
0.00102
784
E46 M3S54 (Rod)
8000
10W60 (+03/2000
0.030
0.050
0.070
0.00118
0.00197
0.00276
49.000
0.0010
1.929
0.00102
784
E60 M5S85 (Rod)
8250
10W60
0.025
0.048
0.070
0.00098
0.00187
0.00276
51.984
0.0009
2.047
0.00091
903
E92 335N54 (Rod)
7000
0-30 to 5W40
0.025
0.048
0.070
0.00098
0.00187
0.00276
50.000
0.0010
1.969
0.00095
737
E92 M3 (2007-2010)S65 (Rod)
8400
10W60
0.030
0.036
0.047
0.00120
0.00140
0.00185
51.984
0.0007
2.047
0.00068
1228
E92 M3 (2011-2013)S65 (Rod)
8400
10W60
0.030
0.042
0.047
0.00120
0.00165
0.00185
51.984
0.0008
2.047
0.00081
1042
F10 M5S63 (Rod)
7000
0-30 to 5W40
0.025
0.048
0.070
0.00098
0.00187
0.00276
53.981
0.0009
2.125
0.00088
796
Ferrari 328 GTS3.2L (Rod)
7700
10W40
0.046
0.068
0.089
0.00181
0.00266
0.00350
43.628
0.0015
1.718
0.00155
498

Last edited by regular guy; 01-19-2014 at 02:53 AM.
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      01-19-2014, 09:41 PM   #1926
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Given rods are ever so increased clearance and mains are actually tighter, can we
Assume M has their continued reason to run tighter than typical clearances?
The oil rec changed but aside from that I assume many on here
Would say these clearances are also too tight compared to industry standards? So will the folks say M screwed up with s54, s65and s85 now think they messed
Up again? I think this shows M chooses these tight specs for a reason and it wasn't a miscalculation as some suggested.
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      01-19-2014, 11:13 PM   #1927
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Quote:
Originally Posted by MrStinky View Post
Given rods are ever so increased clearance and mains are actually tighter, can we
Assume M has their continued reason to run tighter than typical clearances?
The oil rec changed but aside from that I assume many on here
Would say these clearances are also too tight compared to industry standards? So will the folks say M screwed up with s54, s65and s85 now think they messed
Up again? I think this shows M chooses these tight specs for a reason and it wasn't a miscalculation as some suggested.
I don't know...I don't remember anybody saying that. It's certainly not my opinion. But with 1970+ posts in this thread, I definitely don't remember them all.
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      01-19-2014, 11:39 PM   #1928
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Quote:
Back to thinner oil

The oil experts in this thread have always said the TWS 10W60 oil is too thick for the tight clearances of the S65. The F10-S63 M5 engine goes away from the thick 10W60 oil by going back to LL01 0W30-5W40 thinner oil. I will try to get a print out of these oil recommendations along with the latest LL01 approved oil list.

This oil question has my attention. I know you have Clevite looking at some bearings; have they had any recommendations on oil? I am not sure if they really would want to comment but just a thought.

I guess what I really want is BMW to make a unambiguous answer.

And thanks for your work.
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      01-20-2014, 07:41 AM   #1929
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This is a graph showing fail rates by year and mileage at fail by year.
I've had to add some of the years together to even out the numbers a bit.
2008/2009&10/2011/2012&13.
Not much data but it does indicate that the expected downwards trend (newer cars with less miles) reverses about the time that the bearings with the bigger clearance were introduced.


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      01-20-2014, 02:17 PM   #1930
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Quote:
Originally Posted by White 13 View Post
This oil question has my attention. I know you have Clevite looking at some bearings; have they had any recommendations on oil? I am not sure if they really would want to comment but just a thought.

I guess what I really want is BMW to make a unambiguous answer.

And thanks for your work.
Don't forget. Those listed sizes are wear limits, not machining limits which will be much tighter. Also the S65 revs 1250rpm higher than the S63.
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      01-20-2014, 02:47 PM   #1931
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Quote:
Originally Posted by Yellow Snow View Post
Don't forget. Those listed sizes are wear limits, not machining limits which will be much tighter. Also the S65 revs 1250rpm higher than the S63.
...and S63 still specifies thinner oil...
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      01-20-2014, 02:57 PM   #1932
Yellow Snow
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Quote:
Originally Posted by regular guy View Post
...and S63 still specifies thinner oil...
Yes, for a much lower rev limit
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      01-20-2014, 03:13 PM   #1933
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Quote:
Originally Posted by SenorFunkyPants
This is a graph showing fail rates by year and mileage at fail by year.
I've had to add some of the years together to even out the numbers a bit.
2008/2009&10/2011/2012&13.
Not much data but it does indicate that the expected downwards trend (newer cars with less miles) reverses about the time that the bearings with the bigger clearance were introduced.


I wonder if the lack if lead makes the updated bearings less tolerant of metal to metal.
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      01-20-2014, 09:20 PM   #1934
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Isn't there some value to thicker oils for high revving engines? Bearing clearance is one thing but aren't their shearing forces at 8500 ROMs that don't exist at 7200? Is the new m cars
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      01-22-2014, 03:25 PM   #1935
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Shear stability of the oil does not really correlate with the thickness of the oil. It's more about if the oil is loaded with viscosity index improvers (VII) to create a wide multi-grade like 10w-60 or 5w-50. Oils with a higher viscosity index are can be more prone to shearing out of grade.
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      01-22-2014, 03:37 PM   #1936
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Why do high rpm cars then typically have higher spec weighted oils?
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