Just read an article about oil experiments in a subaru GTT (which is the dutch legacy station with a turbo. Article is in Dutch though

http://www.extreme-machines.nl/downloads/Olierapport.doc

 

Iron Copp Lead Alum Sil Chr Tin Sod Pot

Gemiddelde 0W-40 0,0026 0,0019 0,0013 0,0012 0,0027 0,0003 0,0003 0,0009 0,0003

Gemiddelde 10W-40 0,0015 0,0024 0,0007 0,0006 0,0011 0,0002 0,0002 0,0009 0,0002

gemiddelde 5W-50 0,0013 0,0015 0,0006 0,0004 0,0009 0,0001 0,0002 0,0004 0,0015

Gemiddelde totaal 0,0025 0,0026 0,0015 0,0014 0,0024 0,0002 0,0004 0,0015 0,0004

 

(gemiddelde = average)

This table shows the contents of metals in the oil after driving equal distance of 10k km (not testing 1 batch) This shows that on average the 5w50 has the least wear if metals in oil do indicate engine wear.

 

Does anybody here tried this viscosity, cause seems to be a very nice all year around oil.

5W is too light an oil for the old junk I drive.

 

(wondering that maybe 5W is not heavy enough to wash metals out)

The wear numbers do look excellent, but I don't like how the Mobil and Kendall sheared down to a 30 weight oil.

 

There's nothing about an oil that pumps well at low temperatures (5W) that would keep it from sweeping out contaminants. That's nonsense.

 

- Scott

5W is too light an oil for the old junk I drive.

 

(wondering that maybe 5W is not heavy enough to wash metals out)

it only acts like a 5-weight when it's not warmed up, to ease start-up. once you're up to operating temperature, it behaves like a 50-weight, which is plenty thick for just about any street car, even too thick for many.

~Erik~

Have run 20W50 but not 5W50. The problem with trying to compare various viscosity oils even of the same brand is that the additive (antiwear, etc) packs/quantities might be different. Higher viscosity oils naturally have a higher HT/HS high temp/high shear which can give better wear values.

 

I think some people specifically looking for 5W50 run Agip. Shell helix ultra might also have something in that vis range. I'm always wondering if hi vis spread oils use a lot of viscosity index improvers VII's to make it happen.

 

I pasted the values in excel so it would be tabular for easier viewing. I assume these are ppm:

5W40 and 5W50 oils, for the most part, use Group III/IV basestocks, so they need some, but not a lot of VIIs. The Castrol 5W50 is more like a "strong" 5W40, just 0.1 cSt over the line. Kind of a poseur, lol.

 

I think those wear numbers are in percentages. PPM would be somethng like 26 for Iron, 19 for Copper, etc.

I've run Mobil 1 5W-50 in over 120k kms in a LEgacy 2.2, and thousands more in my 2.0 Impreza. Good oil, never had any ill effects. Of course, I do usually run 0W-40 in winter.

 

 

Live in Denmark remember

I plan to continue using Shell Rotella 5-40 in my WRX in summer and 5-30 in winter. Both synthetic.

 

So far, I stick with 5-30 in the wifes 3.0 OBW. I would probably switch to 5-40 if it began using oil from wear, but it is still young in mileage.

 

this of course is in Texas.

 

interesting to see the 5-50 development. Could be helpful for some folks I suspect.

 

 

Carl

Bein' in Texas, I'd recommend y'all to use the 5W-50 - aren't your summers hot ?

Bein' in Texas, I'd recommend y'all to use the 5W-50 - aren't your summers hot ?

 

To me it looked like an ideal oil for both winter and summer (mild Dutch winters though not getting much moren than -15C)

Sure, but even Mobil's own 5W-40 is better suited for freezing weather. It's thinner in the cold than 5W-50.

 

I always like to remind that the xW-xx is just a consumer label that covers a range of viscosity. To be serious about oil choices, you must look at the tech. data sheets.

 

European Shell Ultra 5W-40, for example is so thin that it is almost a 5W-30 oil. Mobil Delvac 1 5W-40 is close to being a 5W-50 ...

I'm reluctant to give up the '5' side of the viscosity spectrum, especially in the 06 with warranty - but I could probably run 10-30 in winter and 10-40 in summer in both my vehicles to good effect. Maybe 10-40 after 100K miles of wear all year round.

 

I dunno

 

Carl