Red Line 75w-90 NS - BMW 330Ci - new Quaife LS 27K

[shanneba]

Latest UOA from my 2003 330Ci BMW Diff. Same ring and pinion, new Quaife LS torsen type carrier. Used the same Red line 75w-90 NS without the limited slip additive as suggested by Quaife.

Two track days, Watkins Glen and Road Atlanta and about 6 or 7 AutoX events. About the same use as the other OUAs.

Code:


Make / Model 2003 BMW 330Ci

engine M54

diff type open open Quaife

Total miles 38,000 53,400 81,000

Brand Castrol? Motul Red Line

Weight 75w-90 75w-90 75w-90 NS

miles on sample 38,000 15,400 27,600

#changes factory fill 2nd change

type SAF-XO?? Gear 300

date 8/5/2006 5/28/2008 01/15/2010



Aluminum 0 1 2

chrom 1 2 2

iron 240 197 190

copper 2 1 1

lead 0 0 1

tin 3 0 0

moly 0 0 0

nickel 0 0 1

manganese 10 6 6

silver 0 0 0

titanium 0 0 0

potassium 1 1 4

boron 216 441 226

silicon 7 19 82

sodium 4 3 10

calcium 7 14 14

magnesium 3 1024 14

phosphorus 1452 1587 1939

zinc 6 6 10

barium 3 0 30



viscosity SUS @ 212 F 74.5 71.1 72.0

viscosity cSt @100C 14.12 13.23 13.47

flashpoint*f 410 395 415

water % 0 0 0

insolubles % 0.1 0.3 0.3










Blackstone comments:
This oil's viscosity measured correctly for a 75W/90-grade differential lube. The main reason for
the high silicon in this sample is due to the silicone lubes and sealers that were used when you installed the
new Quaife torsen-type limited slip unit. All wear metals were steady compared to the previous sample even
thought you ran this oil a lot longer. That means this differential is wearing very well and no mechanical
problems were developing at 81,000 miles. No moisture was found and insolubles were low. Look for even
better results at the next oil change.

 

[Ben99GT]

Looks good, but why did you run NS with a torsen-type LS? The friction modifiers would only be beneficial to you.

 

[sprintman]

I run NS in my Outback trans, not sure I'd run it in an LSD.

 

[Ben99GT]

NS is specifically for manual trans that call for a GL-5 gear lube. For gear type limited slip differentials; however, you want the added slipperiness as it doesn't effect engagement but reduces friction and diff. temps.

 

[unDummy]

Its a Quaife and there are no clutches or cones that require an LSD additive. Its uses friction to work and that friction is the preload and affects bias. NS is the correct fluid as is any NON-LSD gear oil in this type of diff.

Twice the miles on the Redline compared to the Motul and the same wear. And, the Quaife broke in on the Redline??

Since you're tracking it, consider the 75w140NS or a blend. A little more visc might cushion those gears some more.

 

[Ben99GT]

Friction modifiers are beneficial to differentials without clutches as well. I'm not overly familiar with the Quaife differential, but I use friction modified gear oils in a Detroit TrueTrac (torque sensitive, gear type Torsen) differential with great success.

 

[sprintman]

I agree with undummy on the RL 75W140 FWIW.

 

[shanneba]

Ubdummy - Yes the Quaife was installed with the fluid on this UOA. The ring and pinion are the original with 81000 miles now.

BMW suggests a 75-90 without the LS additive for the non M diffs. I believe they use Castrol SAF-XO for non M diffs.

Byrds Auto in UK, where I bought the Quaife suggests a 75w-90 Synthetic without the limited slip additive. The LS additive reduces the effectiveness of the torque biasing of the diff.

 

[sprintman]

Makes sense. Nice LSD. I'd like to see the Wave Trac D LSavailble to E46 owners for comparison..